For you with a LJ your driveline angles might not be too bad but for me in a TJ I think I need a high pinion. With my stretch I'm gunna have a 25-26" driveline.
Nashville TJ's Build - Continued
- Thread starter NashvilleTJ
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For you with a LJ your driveline angles might not be too bad but for me in a TJ I think I need a high pinion. With my stretch I'm gunna have a 25-26" driveline.
OP
I could easily get away with a low pinion rear on my rig - remember I've got an 11" stretch over the stock LJ specs. Although I do like having the pinion up off the rocks. My rear drive shaft is about 33".
Didn't you say you got your parts for your rear end from ECGS? They are having a turkey day sale: https://eastcoastgearsupply.com/
B00mb00m
The Church of Cutting Brakes of Atlas-Front Digs
Supporting Member
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OP
The problem is the high pinion. Many years ago when I bought that '60 I was running a supercharged I6 and 40's. I knew the high pinion was 20-30% weaker than the low pinion, but I though 20-30% weaker than "insanely strong" would be strong enough. I was wrong. With the I6, two bent shafts, a broken shaft, and a fried R&P. Now that I'm running the Hemi.....
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OP
While in a bit of a holding pattern waiting for parts to arrive, I knocked out a quick project which will help with the R&P install. I built a pinion yoke wrench tool to make torqueing down the pinion nut a bit easier.
First, I pulled some 3/8" plate from my cutoff pile, and laid out the tool.
And then I spent some quality time with the plasma cutter and a straight edge, and hacked out the shape.
First, I pulled some 3/8" plate from my cutoff pile, and laid out the tool.
And then I spent some quality time with the plasma cutter and a straight edge, and hacked out the shape.
OP
Then it was over to the drill press to hack out the center hole with a hole saw, and the four mounting holes which line up with the u-bolt holes on the pinion yoke.
A few minutes with the grinder to clean it up a bit, and it's all set.
A few minutes with the grinder to clean it up a bit, and it's all set.
OP
The tool is designed to use a long 3/4" pipe as the lever, and the pinion yoke simply bolts to it. The large hole in the center allows access to the pinion nut.
And lo and behold, while I was working on this the parts from ECGS were delivered.
I'm still waiting for the ARB specific shim kit which I ordered from Northridge 4x4. As I found out late in my research, the ARB does not use a standard '60 shim arrangement on the actuator side of the carrier (it also uses a different bearing cup on that side, which I knew). Instead of using shims between the carrier and the bearing, ARB uses a larger shim between the seal housing and the axle housing. I ordered those this morning, and not sure when they will arrive. NR4x4 did have them in stock, so hopefully soon.
And lo and behold, while I was working on this the parts from ECGS were delivered.
I'm still waiting for the ARB specific shim kit which I ordered from Northridge 4x4. As I found out late in my research, the ARB does not use a standard '60 shim arrangement on the actuator side of the carrier (it also uses a different bearing cup on that side, which I knew). Instead of using shims between the carrier and the bearing, ARB uses a larger shim between the seal housing and the axle housing. I ordered those this morning, and not sure when they will arrive. NR4x4 did have them in stock, so hopefully soon.
Dang Nab Jeff you always do such a great job when you're building/making stuff.
OP
B00mb00m
The Church of Cutting Brakes of Atlas-Front Digs
Supporting Member
Ride of the Month Winner
Fawk! I would've never guessed. I would've also chosen HP it would be great to keep it out of the rocks.
OP
As I understand it, the deal is that on a high pinion in the rear, the orientation of the gears causes the ring and pinion to deflect apart under load. As they deflect, the gears mesh higher on the teeth where they are weaker, and bad things happen (see my ring gear pictures above...). The orientation of the gears in a low pinion causes the ring and pinion to draw together under load, keeping the gear mesh at the strongest part of the gear teeth. There is still some deflection on a low pinion under load, but not nearly as much as In a high pinion.
The opposite happens in the front - which is why a high pinion is stronger than a low pinion as a front axle. This is the reason many TJ guys swap in an HP 30 from an XJ. I think the HP 30 is at least as strong, or stronger than, a low pinion 44 In the front.
To combat the deflection, some axles, such as the HP Rock Jock 70 (Toximus uses these), use a load bolt, which is a bolt that rides behind the ring gear across from the pinion gear, which helps to support the ring gear under load. I believe the 14 bolt uses a load bolt as well.
OP
Happy Thanksgiving! Hope everyone is making the best of it in this strange year.
Northridge4x4 came through. The shim kit and o-rings shipped yesterday from Kentucky, and will be here tomorrow.
Now another issue I need to figure out: The oil slinger was damaged in the failure - you can see the damage here:
When I spoke to ECGS, they told me the install kit does come with a slinger. I'm not sure, but the original looks like it has a hole and a small recess something like a scoop. The slinger which came with the kit does not have the hole. I can't really tell if there is actually a hole, or if the hole I see is simply damage. I'll have to give Dynatrac a call after the holiday.
Anyone happen to know if the ProRock uses a different slinger than a standard '60?
Northridge4x4 came through. The shim kit and o-rings shipped yesterday from Kentucky, and will be here tomorrow.
Now another issue I need to figure out: The oil slinger was damaged in the failure - you can see the damage here:
When I spoke to ECGS, they told me the install kit does come with a slinger. I'm not sure, but the original looks like it has a hole and a small recess something like a scoop. The slinger which came with the kit does not have the hole. I can't really tell if there is actually a hole, or if the hole I see is simply damage. I'll have to give Dynatrac a call after the holiday.
Anyone happen to know if the ProRock uses a different slinger than a standard '60?
OP
After making that my last post, I went out to the shop and took a closer look at the oil slinger. The more I look at it, the more the hole looks like damage. There is also corresponding damage on the bearing cage, so it looks like one of the sheared teeth was simply driven right through the slinger and into the bearing. I may still check with Dynatrac, but I don't think the slinger has a hole, so perhaps crisis averted...
That sure looks like damage to me. I'd think if it was designed to be there, it would be a lot "cleaner."
Wow that is great you are getting the parts so fast. I'm of the same thought that the hole looks like it was due to damage.
And yes you are correct that the high pinion in the rear is weaker than a low pinion. After I'd broken my second R&P I got a low pinion Dana 60 housing to use if I broke another R&P. I took my axle to a axle builder who seemed very knowledgeable about high pinion axles.
He told me that the reason I'd had issues with my last R&P was that it wasn't setup tight enough.
He said the he sets up the high pinion axle in the rear at low backlash recommendation. So if the backlash is 6-10* he'll set it for 5-6* of backlash. And he also set the contact patter more into the teeth.
If you look at the numbers he wrote on the ring gear you can see he set the backlash at 5*. Hope this helps.
And yes you are correct that the high pinion in the rear is weaker than a low pinion. After I'd broken my second R&P I got a low pinion Dana 60 housing to use if I broke another R&P. I took my axle to a axle builder who seemed very knowledgeable about high pinion axles.
He told me that the reason I'd had issues with my last R&P was that it wasn't setup tight enough.
He said the he sets up the high pinion axle in the rear at low backlash recommendation. So if the backlash is 6-10* he'll set it for 5-6* of backlash. And he also set the contact patter more into the teeth.
If you look at the numbers he wrote on the ring gear you can see he set the backlash at 5*. Hope this helps.
OP
OP
Funny talking about backlash - that was the name of my last boat:
I was reading your posts and I started to remember everything he had told me about how he setup gears as I was trying to learn since I can do it but the first failure I had was gears I'd done. The second I took to a shop and then he did the third. As you can see from the date I had 2 years on the gearset he'd setup and with the 38" TSL SX tires.