OP
Re-geared, now I have a vibration above 50 mph
- Thread starter bobthetj03
- Start date
OP
Its about time to get that Rubicon Sahara LJ anyways.
Lol! I don't have your kind of scratch buddy! I'll settle for a 03-04 Rubi TJ, bone stock. Drive home tonight netted no change in vibes. So, from 0.5* to 3* no difference.
IamBR549
TJ Enthusiast
I was waiting to see if anyone commented on wear pattern. Seems like it’s more on the outer edge. That would mean pinion would have to be shimmed to move in some. Curious to see what others say. Maybe take these photos to someone who specializes in driveline and see if this could be causing the noise.
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OP
Well, after driving around for a few days, and even doing some light wheeling locally yesterday, the vibes are no better than they were with the first drive shaft. I'm still going to replace the trany mount for no other reason than it's 15 years old and has 153K on it. Won't change things. Coming to the conclusion there is something amiss in the rear end.
jeepndogs
TJ Enthusiast
That pattern to me looks like it’s a little off center. Could just be the way the light is hitting it.
OP
I'm no expert, so I don't know what a normal pattern looks like. Something is wrong somewhere, just need to isolate it. May be time to involve a professional to take a look. It'll be a road trip to find one, sadly.
jeepndogs
TJ Enthusiast
To me without cleaning it and using pattern paint it looks like there is I much backlash like on the right side middle of this pattern chart. Really hard to say 100% from a photo.
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OP
I haven't dug into the rear diff yet, so I assume that will be the next thing to do. It's been almost 2 years and 15K miles on the new gears with no resolution in the vibes, so I though I should summarize my re gear fiasco and write down to the best of my recollection the order of events. It's a long read so enter at your own risk.
"My re-gear fiasco
Feb, 2016 re-geared the rear axle to 4.56 gears and refreshed the Traclok with new Yukon clutches. Also changed the right rear axle bearing and seal due to the seal leaking a bit. Didn’t have time to re-gear the front, so drove it home in 2wd and immediately had vibrations above 45 mph. Next day removed the front drive shaft just to play it safe and vibrations went away. Drove it for a few weeks to break in the gears, then finally had time to do the front re gear. After re gearing the front and re-installing the drive shaft, the vibrations came back. Drove it for the next few weeks to break in the gears, keeping it below 45 mph to avoid the vibes. Thought that maybe my front drive shaft was the cause of the vibes, I ordered a brand new Adams drive shaft. Had planned trip to Moab in May, so after the 500 mile break in period, changed the gear oil and installed the new front drive shaft. Vibes were still present, but seemed a bit less severe. Decided to pull the front drive shaft again and drive to Moab with it out. Got to Moab, re-installed the front drive shaft for a week of off roading, then removed it for the drive home. 2000 miles round trip. The new gearing was great. The vibes, not so great. When I returned home, I took the jeep to an off road shop near by thinking maybe something was wrong with the front re gear. Noticed at that time the right front axle seal was leaking, so asked the shop to change the seals, and install a new Spicer yoke to upgrade to the stronger u-bolt style. The shop said the gears looked fine and replaced the seals and yoke. Vibes were still there just like before. Thinking that maybe the new front drive shaft I got wasn’t balanced good enough, I called Adams and they sent me a 2nd new front drive shaft. Installed it with no change in vibes. Went to a buddy’s house and swapped his wheel/tires for mine to rule out a wheel/tire issue. Vibes still there even with his known good wheels/tires from his jeep.Took the jeep back to the local off road shop to have them inspect the drivetrain. Shop noticed the rear drive shaft had some play in the slip yoke, so I figured this may have had something to do with the vibes. To verify, I pulled the rear drive shaft and went for a drive in 4hi. Vibes were almost gone. Only a very slight vibe. Decided to save up for a SYE and rebuild of the transfer case. Pulled the TC and took it to a local transmission shop I trust and had them refresh the TC with new bearings, seals, and chain as well as install of an Advanced Adaptor’s SYE. Re-installed the TC, took measurements for a new rear DC drive shaft and called up Adam’s drive shafts to order. Installed the new rear drive shaft, adjusted pinion angle and went for a drive. The vibes were there, but felt different. Above 45 mph I noticed a harmonic wave type of vibe. Still felt it in the seat and floor board. 65 mph and above the harmonic turned into a constant vibe. Tried adjusting the pinion angle at different angles from flat 0* to 1*, 1.5*, 2.0*, 3.0* with no change in vibes. Had my local mechanic check the motor mounts. They checked out good. Replaced the rear track bar with an adjustable one. The factory rear TB bushing didn’t look too good, so I figured it couldn’t hurt. Didn’t change the vibes. I inspected the trany mount and it seemed fine, but ordered a new one anyway. That is next on the list to change. Checked run out on both rear diff yoke and rear TC yoke, plus the new rear drive shaft. Runout was minimal. Called Adams and had them send me a 2nd new rear drive shaft just to rule it out as the problem. Installed 2nd drive shaft. No change. Vibes still there. While the rear driveshaft was out I took it for a drive in 4hi. Vibes almost gone. Only a very slight vibe at 65 mph. During this span of time I have also replaced the control arms with Metal Cloak arms. I had Currie lowers in the front, so when I bought new MC lowers, I put the Currie arms in the rear and the new MC’s up front. Put MC double adjustables in rear uppers.
It’s been almost 2 years and over 15,000 miles on the new gears with no resolution to date. "
"My re-gear fiasco
Feb, 2016 re-geared the rear axle to 4.56 gears and refreshed the Traclok with new Yukon clutches. Also changed the right rear axle bearing and seal due to the seal leaking a bit. Didn’t have time to re-gear the front, so drove it home in 2wd and immediately had vibrations above 45 mph. Next day removed the front drive shaft just to play it safe and vibrations went away. Drove it for a few weeks to break in the gears, then finally had time to do the front re gear. After re gearing the front and re-installing the drive shaft, the vibrations came back. Drove it for the next few weeks to break in the gears, keeping it below 45 mph to avoid the vibes. Thought that maybe my front drive shaft was the cause of the vibes, I ordered a brand new Adams drive shaft. Had planned trip to Moab in May, so after the 500 mile break in period, changed the gear oil and installed the new front drive shaft. Vibes were still present, but seemed a bit less severe. Decided to pull the front drive shaft again and drive to Moab with it out. Got to Moab, re-installed the front drive shaft for a week of off roading, then removed it for the drive home. 2000 miles round trip. The new gearing was great. The vibes, not so great. When I returned home, I took the jeep to an off road shop near by thinking maybe something was wrong with the front re gear. Noticed at that time the right front axle seal was leaking, so asked the shop to change the seals, and install a new Spicer yoke to upgrade to the stronger u-bolt style. The shop said the gears looked fine and replaced the seals and yoke. Vibes were still there just like before. Thinking that maybe the new front drive shaft I got wasn’t balanced good enough, I called Adams and they sent me a 2nd new front drive shaft. Installed it with no change in vibes. Went to a buddy’s house and swapped his wheel/tires for mine to rule out a wheel/tire issue. Vibes still there even with his known good wheels/tires from his jeep.Took the jeep back to the local off road shop to have them inspect the drivetrain. Shop noticed the rear drive shaft had some play in the slip yoke, so I figured this may have had something to do with the vibes. To verify, I pulled the rear drive shaft and went for a drive in 4hi. Vibes were almost gone. Only a very slight vibe. Decided to save up for a SYE and rebuild of the transfer case. Pulled the TC and took it to a local transmission shop I trust and had them refresh the TC with new bearings, seals, and chain as well as install of an Advanced Adaptor’s SYE. Re-installed the TC, took measurements for a new rear DC drive shaft and called up Adam’s drive shafts to order. Installed the new rear drive shaft, adjusted pinion angle and went for a drive. The vibes were there, but felt different. Above 45 mph I noticed a harmonic wave type of vibe. Still felt it in the seat and floor board. 65 mph and above the harmonic turned into a constant vibe. Tried adjusting the pinion angle at different angles from flat 0* to 1*, 1.5*, 2.0*, 3.0* with no change in vibes. Had my local mechanic check the motor mounts. They checked out good. Replaced the rear track bar with an adjustable one. The factory rear TB bushing didn’t look too good, so I figured it couldn’t hurt. Didn’t change the vibes. I inspected the trany mount and it seemed fine, but ordered a new one anyway. That is next on the list to change. Checked run out on both rear diff yoke and rear TC yoke, plus the new rear drive shaft. Runout was minimal. Called Adams and had them send me a 2nd new rear drive shaft just to rule it out as the problem. Installed 2nd drive shaft. No change. Vibes still there. While the rear driveshaft was out I took it for a drive in 4hi. Vibes almost gone. Only a very slight vibe at 65 mph. During this span of time I have also replaced the control arms with Metal Cloak arms. I had Currie lowers in the front, so when I bought new MC lowers, I put the Currie arms in the rear and the new MC’s up front. Put MC double adjustables in rear uppers.
It’s been almost 2 years and over 15,000 miles on the new gears with no resolution to date. "
I agree with the others that the wear pattern doesn't look right. It almost looks like the pinion is in to far to me. I don't think the pattern itself will cause a vibration but rather what is causing the wear pattern. I think you had a shop do the re-gear right? I think I would take it back with this story and all of the things you have done and show them the pattern. If anything it doesn't look right in the picture. That means to get it right they will have to change something like remove a shim or add a shim on the pinion in my opinion. It is probably still under warranty and if it is not it should be. If it is not maybe take it to a completely different shop and have them check it out. If your ring and pinion are not set up correctly, that may or may not mean a thing, but it can cause a different load and cause premature wear on bearings. Just a thought. Although that said, my girlfriends TJ has an obnoxious whine coming from the rear end, and her gear pattern is fine and the fluid looked good, so I am sure she has a pissed off bearing but hers drives smooth just has a whine. Kind of sounds like an old 60's FJ 40.
If yours isn't making noise, but has the slight vibration, I still kind of think it is something in the tires. I know originally you borrowed some from someone, but you have done a ton of work since, I think you and your buddy should try it again if anything just to prove me wrong and shut me up.
Honestly I have seen some really bad set up diffs that didn't make noise or vibrate, and yours doesn't look that bad.
I think if nothing above works out, one last thing to do is remove the radiator cap, push your jeep out of the way, and roll in the new tj and carefully install the radiator cap again.
If yours isn't making noise, but has the slight vibration, I still kind of think it is something in the tires. I know originally you borrowed some from someone, but you have done a ton of work since, I think you and your buddy should try it again if anything just to prove me wrong and shut me up.
Honestly I have seen some really bad set up diffs that didn't make noise or vibrate, and yours doesn't look that bad.
I think if nothing above works out, one last thing to do is remove the radiator cap, push your jeep out of the way, and roll in the new tj and carefully install the radiator cap again.
OP
It's crossed my mind @ac_ . A .99 cent "FOR SALE" would solve it, but I can't in all good conscious dump my problem on some unsuspecting sole, especially a TJ enthusiast, so it'll continue to be my problem to solve. I hear what you're saying about the rear gears, and it will be my next thing to do. Sadly, it was my boss who did the re gear for me. He's done several over the years, including his own Jeep, and had all the nifty tools to accomplish the job, so can't really go there. The local offroad shop that did some of the work on the front diff is no longer an option. I got a bad vibe "pun intended" there, and I didn't mention the fiasco I had with them when I had them replace the front axle seals. This shop is 30 miles away, so I pick up my jeep, drive 30 home, get out of said jeep and notice gear oil puking out both sides of the axle. Another 30 back to the shop, they discover they installed the wrong axle seals. They made it right and fixed it, but time off of work and the back and forth left a bad taste.
So, Sacramento is the closest I can find for a reputable off road shop and that's a 2hr.+ drive.
So, Sacramento is the closest I can find for a reputable off road shop and that's a 2hr.+ drive.
I think you are just arguing with me now. hehe.
What about after you borrow tires and do that test first (free and fun) you buy some beer and pizza and invite your boss over for your 2 year disassemble diff checkout afternoon?
Or move to Arizona, and we can look at it in the man cave. I also have all of the special tools.
What about after you borrow tires and do that test first (free and fun) you buy some beer and pizza and invite your boss over for your 2 year disassemble diff checkout afternoon?
Or move to Arizona, and we can look at it in the man cave. I also have all of the special tools.
OP
Well I am almost exactly 4 hours south of the Grand Canyon, but if you are coming from where you are coming from what's another 4 hours right?
OP
NICE!!
Here is my setup, although I don't have this truck anymore. had to trade it in for a 4x4
White Shadow 99
Member
Bob, I have an 06 LJ with vibes after a regear to 5.13s. Mine has improved but not gone. I am in West Sacramento you should give me a call and we can discuss. I recently changed out my transfer case mount and that helped quite a bit. xxxxxxxxx (personal phone number deleted)
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OP
Hey there. I'll give you a call. I still need to replace my trany mount. Have a new one. Just need to find the time to do it. I called Hunter 4x4 in Citrus Heights the other day and talked to the owner about my issue. He suggested to check a few things. He even said he has a XJ that he can't quite get all the vibes out after regearing it. I played around with the pinion angle again and adjusted the rear to .05* lower than the drive shaft angle. No change. After I change the trany mount I am going to start from scratch, remove the front drive shaft, check the torque on both front yokes and try getting the rear to cooperate better, then go from there. Don't know what else to do.
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