Is that a HSS tool bit your using for facing the spacers? It's been a long time since I have seen one in action. Had to grind more than a few in trade school many years ago.
Great build thread with excellent detail. Keep up the great work
OldBuzzard's 2005 Jeep Wrangler Unlimited
- Thread starter OldBuzzard
- Start date
Is that a HSS tool bit your using for facing the spacers? It's been a long time since I have seen one in action. Had to grind more than a few in trade school many years ago.
Great build thread with excellent detail. Keep up the great work
OP
Yes, plain old HSS. I have a carbide tool, but this round-faced HSS tool seems to work best for me on my wimpy lathe.
Freshman year was basic engine lathe's (Southbend belt driven) and that's all we used, many burnt finger tips grinding them. Today they just throw them on a CNC lathe with the best tooling available. Learned so much on those manual lathes.
OP
Sometimes I think having a CNC lathe would be really nice, but I kind of like doing it manually. I just wish I had bought a little sturdier machine 30 years ago. This one isn't terribly rigid, so I have to take tiny cuts, and it takes forever to do anything. Still, I've used it to make telescope parts, motorcycle parts, tools, Jeep parts, plumbing parts.
OP
Tranny skid
With a 1-1/4" body lift (BL) and a 1" motor mount lift (MML) in place, it's time to do a partial tummy tuck. Under Cover Fabworks (UCF) makes tranny skids in three different depths: "No Body Lift", "Extra Clearance", and "Ultra High Clearance". And you can order steel or aluminum, in two thicknesses. I bought the Extra Clearance skid in 3/8" aluminum, along with an aluminum engine skid. Expensive, yes. Buy once, cry once. A Black Friday 15% discount eased the pain a little.
The 2005 OEM "shovel" is 4-1/2" deep on the outside, and 3-5/8" deep inside (mounting flange down to where the tranny mount sits), and weighs 42 pounds. The UCF Extra Clearance skid is 2-3/8" deep on the outside, and 1-1/4" deep inside, and weighs 38 pounds (this is the "thick" 3/8" aluminum one).
So ground clearance will increase by 2-1/8". But the tranny will move up 2-3/8", increasing driveline angles accordingly. Since I have a 2-1/2" spring & spacer lift, it will be an effective driveline lift of 4-7/8". I'm keeping the OEM tranny mount because I don't want the extra vibrations from a UCF LOPRO mount.
Installing the new skid is quick and easy. Support the tranny, remove 6 bolts and 4 nuts, drop the OEM skid, lift the new skid, install the bolts and nuts. If only that was all there was to it.
With the new skid holding the transmission higher, the fan rubs firmly on the bottom of the shroud. I removed the fan, and the shroud, and drilled new holes in the shroud to lower it by about 1/2". I also had to trim away some extra plastic to make room for the bolts and washers.
With an effective 4-7/8" driveline lift, this LJ had driveline vibrations pretty bad. I had expected that, but I also had expected to be able to add a skid spacer to eliminate the vibes until a later date. After spending more time and money making custom aluminum 1/2" spacers, and then increasing the skid plate drop to 1" by adding more 1/2" spacers, the vibes were reduced but still there.
Adjustable upper rear control arms
There was a 4° mismatch between the rear pinion and the tranny shaft angles. The original two-U-joint driveshaft is still in place. I installed Savvy double-adjustable upper rear control arms, and tilted the pinion down to match the tranny shaft. This matches the U-joint angles, but increases the angles of both U-joints to 13°. According to Tom and Shawn Wood, this is pushing the limits, but sometimes works. In this case, vibrations were reduced again, but still present.
To confirm where the vibrations I was hearing and feeling were coming from, I removed the rear driveshaft and drove it in front wheel drive. It was very noticeably smoother and quieter. So a 1" spacer didn't fix it, and I didn't really want a spacer in there anyway. And even with the spacer, aligning the pinion angle with the tranny angle didn't fix it.
SYE & DC driveshaft
I knew beforehand that I might need an SYE and a DC driveshaft, but I thought I could put it off for a while. I kept reminding myself that it's an LJ, maybe it won't need them. Wrong-O.
I installed an Advance Adapters Slip Yoke Eliminator (SYE) and a Tom Wood's Double Cardan (DC) driveshaft (stories for another day, perhaps). And removed the skid spacer, bolting the skid up against the frame. And lowered the exhaust hanger (see below). I tilted the rear pinion up to almost align with the driveshaft, about 1° low.
Verified that the shocks don't hit the lower spring perches, and the JKS track bar joint swivels safely in the axle-end bracket, and it doesn't hit the gas tank skid, and the fan doesn't hit the shroud. And my shifter is properly centered now (problem from installing MML, above). I can put the leather boot and bezel back in place, with plenty of clearance to shift into all gears.
Now, 70 MPH is nice and smooth, no more driveline vibes. And it has a partial tummy tuck — not flat, but considerably slimmer.
With a 1-1/4" body lift (BL) and a 1" motor mount lift (MML) in place, it's time to do a partial tummy tuck. Under Cover Fabworks (UCF) makes tranny skids in three different depths: "No Body Lift", "Extra Clearance", and "Ultra High Clearance". And you can order steel or aluminum, in two thicknesses. I bought the Extra Clearance skid in 3/8" aluminum, along with an aluminum engine skid. Expensive, yes. Buy once, cry once. A Black Friday 15% discount eased the pain a little.
The 2005 OEM "shovel" is 4-1/2" deep on the outside, and 3-5/8" deep inside (mounting flange down to where the tranny mount sits), and weighs 42 pounds. The UCF Extra Clearance skid is 2-3/8" deep on the outside, and 1-1/4" deep inside, and weighs 38 pounds (this is the "thick" 3/8" aluminum one).
So ground clearance will increase by 2-1/8". But the tranny will move up 2-3/8", increasing driveline angles accordingly. Since I have a 2-1/2" spring & spacer lift, it will be an effective driveline lift of 4-7/8". I'm keeping the OEM tranny mount because I don't want the extra vibrations from a UCF LOPRO mount.
Installing the new skid is quick and easy. Support the tranny, remove 6 bolts and 4 nuts, drop the OEM skid, lift the new skid, install the bolts and nuts. If only that was all there was to it.
With the new skid holding the transmission higher, the fan rubs firmly on the bottom of the shroud. I removed the fan, and the shroud, and drilled new holes in the shroud to lower it by about 1/2". I also had to trim away some extra plastic to make room for the bolts and washers.
With an effective 4-7/8" driveline lift, this LJ had driveline vibrations pretty bad. I had expected that, but I also had expected to be able to add a skid spacer to eliminate the vibes until a later date. After spending more time and money making custom aluminum 1/2" spacers, and then increasing the skid plate drop to 1" by adding more 1/2" spacers, the vibes were reduced but still there.
Adjustable upper rear control arms
There was a 4° mismatch between the rear pinion and the tranny shaft angles. The original two-U-joint driveshaft is still in place. I installed Savvy double-adjustable upper rear control arms, and tilted the pinion down to match the tranny shaft. This matches the U-joint angles, but increases the angles of both U-joints to 13°. According to Tom and Shawn Wood, this is pushing the limits, but sometimes works. In this case, vibrations were reduced again, but still present.
To confirm where the vibrations I was hearing and feeling were coming from, I removed the rear driveshaft and drove it in front wheel drive. It was very noticeably smoother and quieter. So a 1" spacer didn't fix it, and I didn't really want a spacer in there anyway. And even with the spacer, aligning the pinion angle with the tranny angle didn't fix it.
SYE & DC driveshaft
I knew beforehand that I might need an SYE and a DC driveshaft, but I thought I could put it off for a while. I kept reminding myself that it's an LJ, maybe it won't need them. Wrong-O.
I installed an Advance Adapters Slip Yoke Eliminator (SYE) and a Tom Wood's Double Cardan (DC) driveshaft (stories for another day, perhaps). And removed the skid spacer, bolting the skid up against the frame. And lowered the exhaust hanger (see below). I tilted the rear pinion up to almost align with the driveshaft, about 1° low.
Verified that the shocks don't hit the lower spring perches, and the JKS track bar joint swivels safely in the axle-end bracket, and it doesn't hit the gas tank skid, and the fan doesn't hit the shroud. And my shifter is properly centered now (problem from installing MML, above). I can put the leather boot and bezel back in place, with plenty of clearance to shift into all gears.
Now, 70 MPH is nice and smooth, no more driveline vibes. And it has a partial tummy tuck — not flat, but considerably slimmer.
OP
Lowered exhaust hanger
When installing the UCF Extra Clearance skid, the exhaust hanger gets lifted up, hoisting the catalytic converter to within about 1/4" of the insulation under the tub. It clears, but just barely, and has essentially no room to "breathe". Your passenger's feet are going to get very uncomfortable.
I removed the tranny mount/exhaust hanger. At first glance, it looks like you can cut it to use both existing holes, aligning them for a single bolt. That would lower the hanger by about 1-9/16". But I didn't think it was safe to drop it that low.
I decided to use the top existing hole, with a new hole just above the bottom hole. That lowers it about 1-1/16", with enough room for a new hole which doesn't overlap the bottom hole. I measured, marked, cut, filed, and drilled the exhaust hanger. Cleaned and touched up the cut edges with Rust-Oleum protective enamel.
I used two 5/16-24 x 1" and one 3/8-24 x 1" grade 8 bolts and nuts. Added blue Loctite 242, torqued the 5/16" bolts to 15 ft lb, torqued the 3/8" bolt to 23 ft lb (just guessed at the torque requirements).
After installing this modified hanger, along with the UCF skid, the cat has about 1-1/2" of space above it, and about 1/2" of space below it. It's a good thing I didn't lower it any farther, the cat would have hit the tranny mount crossmember in the bottom of the skid.
When installing the UCF Extra Clearance skid, the exhaust hanger gets lifted up, hoisting the catalytic converter to within about 1/4" of the insulation under the tub. It clears, but just barely, and has essentially no room to "breathe". Your passenger's feet are going to get very uncomfortable.
I removed the tranny mount/exhaust hanger. At first glance, it looks like you can cut it to use both existing holes, aligning them for a single bolt. That would lower the hanger by about 1-9/16". But I didn't think it was safe to drop it that low.
I decided to use the top existing hole, with a new hole just above the bottom hole. That lowers it about 1-1/16", with enough room for a new hole which doesn't overlap the bottom hole. I measured, marked, cut, filed, and drilled the exhaust hanger. Cleaned and touched up the cut edges with Rust-Oleum protective enamel.
I used two 5/16-24 x 1" and one 3/8-24 x 1" grade 8 bolts and nuts. Added blue Loctite 242, torqued the 5/16" bolts to 15 ft lb, torqued the 3/8" bolt to 23 ft lb (just guessed at the torque requirements).
After installing this modified hanger, along with the UCF skid, the cat has about 1-1/2" of space above it, and about 1/2" of space below it. It's a good thing I didn't lower it any farther, the cat would have hit the tranny mount crossmember in the bottom of the skid.
deadbeat son
TJ Addict
Your post in the narrow and tall stance thread drove me here to your build thread. I just read it all, and I have to compliment you on a quality tasteful build and thank you for such excellent documentation. Cheers!
OP
Engine skid
I bought a UCF 1/4" aluminum engine skid along with the tranny skid. The skid is superb. The hardware which comes with it, not so much. Missing washers, too-short bolts for the motor mount brackets, too-short button bolts to reach through the 3/8" tranny skid. A front brace needs to have a clearance cut made. I don't mind doing some fab work, it's fun, but a ready-to-install kit should be ready to install. The instructions are fair, but they say the motor mount bolts will hold themselves in place. They lie. I had to cut down a 9/16" box end wrench to hold them.
The hardest part (well, almost) of installing it was cleaning off the glue from the shipping tape. Alcohol, paint thinner, acetone, nothing works very well. A lot more acetone, and a lot of scraping and scrubbing finally got it clean, but for a while there I thought I would rub through the quarter-inch aluminum before I got rid of the glue.
I test-installed the brackets and braces (below), and cut a notch in the driver brace. I cleaned and primed and painted and baked the bare steel brackets and braces.
The instructions are completely unclear on the fact that the motor mount brackets are identical, not mirrors of each other, so one faces forward and the other faces rearward. And they don't say which one goes which way. You have to look at pictures and read forums to figure it out. The passenger side rounded hangy-downy goes upward and forward, hanging down, and the driver side one goes upward and rearward, hanging down. The bolts aren't long enough to get a good bite in the nut, to bend the bracket down into the curve, so I used longer ones initially. I used a shortened box end wrench to hold the bolt heads in the short, curved slots.
More looking at pictures and forums to figure out which way the long braces face. I guess I should be grateful I got any instructions at all. The passenger side brace went in fine, but the driver side (longer) brace didn't. I cut a notch in the upper end where it had some interference with a bolt/nut.
I had to re-drill the front holes in the skid. Apparently UCF had drilled them with the metal flat, and then curved the metal, squishing the holes a little.
With the front braces holding up the front end, but not tightened, I had to twist the rear end of the skid around to get it lined up. After aligning the oil drain hole with the plug, I jacked the engine skid up, lifting the Jeep a little, to hold the engine skid tight against the tranny skid. The tranny skid is thick and hard. I drilled pilot holes, and then 3/8" holes with a new sharp bit. Without a vehicle lift, but up on tall jack stands, you have very little room to get behind the drill. Expect sore arms and shoulders.
The supplied button bolts won't go into the nylon lock on the nyloc nuts with this thick tranny skid. Instead of replacing the bolts, I just used plain nuts with 243 Threadlocker.
A test drive showed that nothing squeaked, bonked, or fell off. Good. Now to go find some big rocks to play on.
A while later, an oil change showed that oil goes everywhere, even if you can get 99% of it through that oval hole. I see a Fumoto or Stahlbus or No-Spill valve drain in my future.
I bought a UCF 1/4" aluminum engine skid along with the tranny skid. The skid is superb. The hardware which comes with it, not so much. Missing washers, too-short bolts for the motor mount brackets, too-short button bolts to reach through the 3/8" tranny skid. A front brace needs to have a clearance cut made. I don't mind doing some fab work, it's fun, but a ready-to-install kit should be ready to install. The instructions are fair, but they say the motor mount bolts will hold themselves in place. They lie. I had to cut down a 9/16" box end wrench to hold them.
The hardest part (well, almost) of installing it was cleaning off the glue from the shipping tape. Alcohol, paint thinner, acetone, nothing works very well. A lot more acetone, and a lot of scraping and scrubbing finally got it clean, but for a while there I thought I would rub through the quarter-inch aluminum before I got rid of the glue.
I test-installed the brackets and braces (below), and cut a notch in the driver brace. I cleaned and primed and painted and baked the bare steel brackets and braces.
The instructions are completely unclear on the fact that the motor mount brackets are identical, not mirrors of each other, so one faces forward and the other faces rearward. And they don't say which one goes which way. You have to look at pictures and read forums to figure it out. The passenger side rounded hangy-downy goes upward and forward, hanging down, and the driver side one goes upward and rearward, hanging down. The bolts aren't long enough to get a good bite in the nut, to bend the bracket down into the curve, so I used longer ones initially. I used a shortened box end wrench to hold the bolt heads in the short, curved slots.
More looking at pictures and forums to figure out which way the long braces face. I guess I should be grateful I got any instructions at all. The passenger side brace went in fine, but the driver side (longer) brace didn't. I cut a notch in the upper end where it had some interference with a bolt/nut.
I had to re-drill the front holes in the skid. Apparently UCF had drilled them with the metal flat, and then curved the metal, squishing the holes a little.
With the front braces holding up the front end, but not tightened, I had to twist the rear end of the skid around to get it lined up. After aligning the oil drain hole with the plug, I jacked the engine skid up, lifting the Jeep a little, to hold the engine skid tight against the tranny skid. The tranny skid is thick and hard. I drilled pilot holes, and then 3/8" holes with a new sharp bit. Without a vehicle lift, but up on tall jack stands, you have very little room to get behind the drill. Expect sore arms and shoulders.
The supplied button bolts won't go into the nylon lock on the nyloc nuts with this thick tranny skid. Instead of replacing the bolts, I just used plain nuts with 243 Threadlocker.
A test drive showed that nothing squeaked, bonked, or fell off. Good. Now to go find some big rocks to play on.
A while later, an oil change showed that oil goes everywhere, even if you can get 99% of it through that oval hole. I see a Fumoto or Stahlbus or No-Spill valve drain in my future.
OP
Steering skid
I looked at dozens of brands of steering box skids on Amazon and various 4WD places. Most have pretty similar specs (3/16" steel box, various attachment holes). Prices vary all over the place. But many were absolutely identical, under various brands, with prices from $40 to $60. All of these identical ones under different brands use the exact same dumb photos. They show a skid held on with one tight bolt, one very loose bolt, and one missing bolt.
I found one on Amazon, listed as "Used: Very Good", with free returns, for $30. How bad could it be? I could always send it back. It arrived in excellent condition, with a few scuffs. The steering box bolt had been installed, but neither of the bumper bolt holes had the slightest marks. What good is a skid held on with one bolt?
I removed the long steering box bolt, and the bumper to get the third bolt in. I cut a 1/2-13 bolt to just fit under the tubular frame crossbar, and installed it with Loctite 243.
Then I reinstalled the bumper with the steering skid attached, and reinstalled the very long steering box bolt.
Ready to go.
I looked at dozens of brands of steering box skids on Amazon and various 4WD places. Most have pretty similar specs (3/16" steel box, various attachment holes). Prices vary all over the place. But many were absolutely identical, under various brands, with prices from $40 to $60. All of these identical ones under different brands use the exact same dumb photos. They show a skid held on with one tight bolt, one very loose bolt, and one missing bolt.
I found one on Amazon, listed as "Used: Very Good", with free returns, for $30. How bad could it be? I could always send it back. It arrived in excellent condition, with a few scuffs. The steering box bolt had been installed, but neither of the bumper bolt holes had the slightest marks. What good is a skid held on with one bolt?
I removed the long steering box bolt, and the bumper to get the third bolt in. I cut a 1/2-13 bolt to just fit under the tubular frame crossbar, and installed it with Loctite 243.
Then I reinstalled the bumper with the steering skid attached, and reinstalled the very long steering box bolt.
Ready to go.
OP
Side skirts
After the body lift, I made crack covers for the front and rear. But the sides still looked dumb with a big gap. Someone gave me a couple of Z-section galvanized steel 22 gauge strips. They're 2" tall, with 1" tabs.
I cut them to match the length and shape of the side steps.
After cleaning, priming, and painting them, I mounted them to the three tabs under the body. One side fit easily with a little clearance, but the other side needed some small spacers to lift it up to clear the side steps. A gap between the step and skirt is needed for body flex.
They just kind of disappear, but your eye is no longer easily drawn to that ugly gap.
I've looked for a source for these steel Z-section strips, but have not found them anywhere.
After the body lift, I made crack covers for the front and rear. But the sides still looked dumb with a big gap. Someone gave me a couple of Z-section galvanized steel 22 gauge strips. They're 2" tall, with 1" tabs.
I cut them to match the length and shape of the side steps.
After cleaning, priming, and painting them, I mounted them to the three tabs under the body. One side fit easily with a little clearance, but the other side needed some small spacers to lift it up to clear the side steps. A gap between the step and skirt is needed for body flex.
They just kind of disappear, but your eye is no longer easily drawn to that ugly gap.
I've looked for a source for these steel Z-section strips, but have not found them anywhere.
OP
Thanks for the tip. I'll try WD40 for glue — big box stores should hand out a vial of glue remover with every purchase, since they put those stupid stickers on everything.
OP
Diff Guards
I wanted a Barnett, but they became hard to get just before I decided to buy. I like a guard which sits away from the diff cover, giving some protection and dent room before anything even touches the cover itself. Warn, and several other brands, looked okay, but Rock Hard looks just like them, with the same specs, for less money. So I bought a Dana 30 and Dana 44 guard from Rock Hard.
I ran into several problems on the front one. It wouldn't sit down against diff cover. The inside edge of the guard was hitting the curve of the diff cover before it was seated.
I talked with Rock Hard, and they've never had a single complaint about this problem before. After comparing the numbers on my diff cover, we decided that mine was from a different OEM batch than every other one we could find. Rock Hard offered to grind the guard and re-powder-coat it, but I just did it myself, and painted it.
Now the guard sits flush with the diff cover, but the base is warped.
I experimented with bolting it to the Dana 30, and it flexed down against the diff to where it was almost, but not quite, flat. I decided to go ahead and try it, hoping the sealer would do its job, and watch for leaks later.
I didn't like the Allen-wrench button head screws which came with it, so I replaced them with flange-head bolts. But the bolt flange was blocked by part of the guard in a couple of places, so I had to file the spots a little wider.
I installed the diff cover with Permatex Red RTV Silicone High Temperature Gasket Maker, and put the guard in place, and snugged the bolts finger tight until the sealer began to squeeze out of the edges. I left it to vulcanize for an hour, and then torqued the bolts to 30 ft. lbs. (per FSM). Much later, I found that considerably lower torque is preferred (12-17 ft lbs), and Rock Hard recommends 20 ft lbs. After letting it cure for another 24 hours, I lubed the diff with Valvoline High Performance 80W-90 Gear Oil (conventional). Months later, I have had no leaks.
The rear guard for the Dana 44 fit well, with only a slight base warpage which tightened flat against the diff cover.
I've bumped the guards on rocks a few times, gently, and I'm glad they're there.
I wanted a Barnett, but they became hard to get just before I decided to buy. I like a guard which sits away from the diff cover, giving some protection and dent room before anything even touches the cover itself. Warn, and several other brands, looked okay, but Rock Hard looks just like them, with the same specs, for less money. So I bought a Dana 30 and Dana 44 guard from Rock Hard.
I ran into several problems on the front one. It wouldn't sit down against diff cover. The inside edge of the guard was hitting the curve of the diff cover before it was seated.
I talked with Rock Hard, and they've never had a single complaint about this problem before. After comparing the numbers on my diff cover, we decided that mine was from a different OEM batch than every other one we could find. Rock Hard offered to grind the guard and re-powder-coat it, but I just did it myself, and painted it.
Now the guard sits flush with the diff cover, but the base is warped.
I experimented with bolting it to the Dana 30, and it flexed down against the diff to where it was almost, but not quite, flat. I decided to go ahead and try it, hoping the sealer would do its job, and watch for leaks later.
I didn't like the Allen-wrench button head screws which came with it, so I replaced them with flange-head bolts. But the bolt flange was blocked by part of the guard in a couple of places, so I had to file the spots a little wider.
I installed the diff cover with Permatex Red RTV Silicone High Temperature Gasket Maker, and put the guard in place, and snugged the bolts finger tight until the sealer began to squeeze out of the edges. I left it to vulcanize for an hour, and then torqued the bolts to 30 ft. lbs. (per FSM). Much later, I found that considerably lower torque is preferred (12-17 ft lbs), and Rock Hard recommends 20 ft lbs. After letting it cure for another 24 hours, I lubed the diff with Valvoline High Performance 80W-90 Gear Oil (conventional). Months later, I have had no leaks.
The rear guard for the Dana 44 fit well, with only a slight base warpage which tightened flat against the diff cover.
I've bumped the guards on rocks a few times, gently, and I'm glad they're there.
Love you're attend to detail and creative solutions to improve both off road performance and appearance. Thank you for for a great job documenting everything so well.
OP
The OEM circuit takes headlight power directly from the multifunction switch (headlight switch on steering column). So the fairly heavy current feeding the headlights goes through the small switch contacts, and then through long, not-very-heavy wiring to reach the headlights. There can be quite a bit of resistance in that circuit. That's one of the reasons the OEM headlights are so mediocre.
Running a heavy gauge wire to feed relays near the headlights gets good power where it's needed, directly into the headlights, with very low resistance. And it reduces the load on the multifunction switch.
I just wired it the way many people think Chrysler should have done it in the first place.
Got it. I found a prewired harness on this forum that does what you made. I will be buying the same Hella housing that used but with Sylvania 9003 Ultra bulbs. I have them in my Silverado. They are a whiter light. Thanks for the great post.
OP
Gears / front ELocker / rear LSD clutches
With the old 31" tires the OEM 3.73 gears were okay, but not great, especially when pulling a trailer. I knew I would have to regear when I switched to 33-inchers. I read a lot of threads here, finding the most common recommendation of 4.56 with my tranny and tires. And I spent a lot of time on grimmjeeper playing with the numbers.
I do my own work on almost everything, but this Jeep is my daily driver. I knew it would take me many days to swap out the gears if I did it myself (my first time for gears). So I used a highly recommended Denver shop: The Edge Automotive. I asked about Revolution gears, but Edge is a stocking Yukon dealer, and they won't do other brands.
I had them install Yukon 4.56 gears, and an Eaton ELocker in the front, and replace the Trac-Lok clutch disks in the rear LSD. I wired the ELocker myself. The Eaton rocker switch is huge. So instead, I used a GCD rocker switch which snaps right into the switch bank in the dash.
I looked up the gear break-in process from Yukon and Revolution and followed some of their stuff, along with the Edge break-in sheet. I broke in the gears very gently, low speed for the first 100 miles, then easy city/highway to 500 miles. Edge replaced the break-in lube and inspected the gear wear pattern. They said their break-in lube was something conventional, but their permanent lube turned out to be a synthetic. I'll be switching back to conventional one of these days (see the many discussions on the forum).
After the full break-in and re-lube, I drove it another 500 miles, and then started another gentle break-in pulling my trailer. It weighs about 2800 to 3000 pounds, and I lug it up several mountain passes a couple times a year. So I gave it 100 miles of easy low speed, and then another 100 miles of easy highway speed, before heading up to the high country.
I had a front axle seal leak, so I took the Jeep back to Edge. They replaced the seal under warranty. Their service was outstanding, especially compared to some of the other shops I've visited for previous vehicles.
The front ELocker is great. I've used it several times, usually waiting until I get some slip just so I can see the difference. Of course, shortly after getting this work done, I found a few places which made me wish I had a rear locker too, instead of an LSD. I'll add that to my to-do list.
The lamp in the ELocker switch is easy to miss. At some point I'll add a flashing LED higher up on the dash to remind me it's on.
The 4.56 gears are just right. I can use 6th gear again. Pulling the trailer is better - I don't hold up mountain traffic quite as much as I used to. They're great on the trail, too.
With the old 31" tires the OEM 3.73 gears were okay, but not great, especially when pulling a trailer. I knew I would have to regear when I switched to 33-inchers. I read a lot of threads here, finding the most common recommendation of 4.56 with my tranny and tires. And I spent a lot of time on grimmjeeper playing with the numbers.
I do my own work on almost everything, but this Jeep is my daily driver. I knew it would take me many days to swap out the gears if I did it myself (my first time for gears). So I used a highly recommended Denver shop: The Edge Automotive. I asked about Revolution gears, but Edge is a stocking Yukon dealer, and they won't do other brands.
I had them install Yukon 4.56 gears, and an Eaton ELocker in the front, and replace the Trac-Lok clutch disks in the rear LSD. I wired the ELocker myself. The Eaton rocker switch is huge. So instead, I used a GCD rocker switch which snaps right into the switch bank in the dash.
I looked up the gear break-in process from Yukon and Revolution and followed some of their stuff, along with the Edge break-in sheet. I broke in the gears very gently, low speed for the first 100 miles, then easy city/highway to 500 miles. Edge replaced the break-in lube and inspected the gear wear pattern. They said their break-in lube was something conventional, but their permanent lube turned out to be a synthetic. I'll be switching back to conventional one of these days (see the many discussions on the forum).
After the full break-in and re-lube, I drove it another 500 miles, and then started another gentle break-in pulling my trailer. It weighs about 2800 to 3000 pounds, and I lug it up several mountain passes a couple times a year. So I gave it 100 miles of easy low speed, and then another 100 miles of easy highway speed, before heading up to the high country.
I had a front axle seal leak, so I took the Jeep back to Edge. They replaced the seal under warranty. Their service was outstanding, especially compared to some of the other shops I've visited for previous vehicles.
The front ELocker is great. I've used it several times, usually waiting until I get some slip just so I can see the difference. Of course, shortly after getting this work done, I found a few places which made me wish I had a rear locker too, instead of an LSD. I'll add that to my to-do list.
The lamp in the ELocker switch is easy to miss. At some point I'll add a flashing LED higher up on the dash to remind me it's on.
The 4.56 gears are just right. I can use 6th gear again. Pulling the trailer is better - I don't hold up mountain traffic quite as much as I used to. They're great on the trail, too.
OP
Metalcloak Corner Travel Index trailer
When I had my gear inspection and re-lube, Edge had the Metalcloak Corner Travel Index trailer available free for customers that day. So of course I drove up on the trailer and had it checked.
It lifted 17" on the right front and 14" on the left rear. On their sheet, they wrote:
14 + 17 = 31 x 2 = 62 x 10 = 620
Okay, I have a CTI of 620 on this 2" lifted Jeep. Better than stock, but could be better yet. It was fun watching other guys with much more radical Jeeps testing theirs.
You can read about the trailer here:
https://modernjeeper.com/corner-travel-index-cti-whats-that/
https://metalcloak.com/article-282
When I had my gear inspection and re-lube, Edge had the Metalcloak Corner Travel Index trailer available free for customers that day. So of course I drove up on the trailer and had it checked.
It lifted 17" on the right front and 14" on the left rear. On their sheet, they wrote:
14 + 17 = 31 x 2 = 62 x 10 = 620
Okay, I have a CTI of 620 on this 2" lifted Jeep. Better than stock, but could be better yet. It was fun watching other guys with much more radical Jeeps testing theirs.
You can read about the trailer here:
https://modernjeeper.com/corner-travel-index-cti-whats-that/
https://metalcloak.com/article-282
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