hornetman

I have about 150 miles since upgrading gears to 4.88. I have been noticing for last 6-8 months this vibration, seams to be more noticeable since I bumped up to STT PRO 35's and now with new gears installed last week. I've looked close at the driveshafts and I'm wondering if my front may be the culprit of what I feel. Usually it occurs over 50MPH and around 25-2700 RPM.



This and below pic is my area of concern. The joint feels tight but can see where some grease has splattered out from the joint.



Rear shaft I can't find any problems. I have an appointment in Friday to take back to where I had gears installed. I don't want to void my regear warrantee so was going to have them take a look to make sure no problem with the gear install.

Any suggestions or trying to figure out if in fact my problem is with the drive shaft. I have 2 1/2 TeraFlex lift, no problem with steering or death wobble. I'm just a little concerned with the feel.

karls10jk

The best way to know for sure (beyond the 'expert advice' from the forum) would be to pull that driveshaft and drive it for a while. The shifts will feel different and driving is slightly different but you should be able to tell if it's your driveshaft pretty quickly.

Teraflex offers a rebuild/ upgrade kit for that joint if you do find it to be defective.

Smudgeontheglass

If it is only RPM related then you are probably on the right track. The grease splattered out from the driveshaft joint should be a pretty telltale sign of failure, but the boot looks good and not torn so I'm personally a bit confused. Since it is just your front drive shaft, you could also try simply pulling it off and seeing if the vibrations are still occurring. You could try the same thing with the rear drive shaft but nobody will recommend you do that for very long.

If it is speed related, it is going to do more with the alignment and tires. At 2.5" you should have some sort of castor correction or else you can have those sorts of issues on larger tires.

hornetman

I should say that it appears to be more noticeable recently, I was running 33 AT's Pro Comps until about 3 weeks ago. First started noticing in the Winter which was very faint bib, I don't even know if I could call it a vibe but could feel it through my gas pedal, I would turn my radio off but couldn't isolate. I was worried that it might be a throw out bearing but it always seamed to occur at higher speeds 50+ and 2500+ RPM. Seeing how I just had gears installed and shafts have been torque striped I opted to take back and have the shop reinspect the install. I have been taking it real easy trying to break the gears in but haven't even put it in 6th gear because it doesn't feel right. The shop that did the gears test drive before and after and as far as I know nothing was noted. If it wasn't for having the new gears installed I would pull the shaft to see how it feels. I also noticed the front shaft was very hot after driving home from work, this could be normal being so close to exhaust and the engine.

karls10jk

It makes no difference and there's no reason you couldn't run with just the front shaft indefinitely even. It will handle slightly differently- yes I've driven mine like that for a week and there were no catastrophic failures out melt downs.

Biginboca

I agree I've driven for weeks without a front shaft. And weeks without a rear shaft also including a 4 hour road trip on the highway at 80mph in front wheel drive only, and in both cases I never had any issues from driving with the missing driveshaft.

BFGMallTerrains

After I regeared my '13 auto to 4.10 and 33" tires I had a rhythmic pulsating vibe that started at 45 mph to 65mph. Annoying as hell. Switched to 35's and regeared again to 4.56. Vibe gone completely. Had it checked several times by different sources and determined that the driveshaft spinning faster was the cause. Didn't change any driveshafts so must have been the frequency of the 33/4.10 combo. Or maybe has to do with the additional width of the tires making more grip. Who the hell knows.
About the shifting, it's a well known issue that the autos seem to have a weird 1st to 2nd "double shift" which I also experienced, but it's pretty much gone when I made the 4.56/35" change

shabbernigdo

i have a similar issue on mine as well. it started after i installed the aev 2.5 lift and 35 inch tires. its a low rumble that seems to come and go. had my tires balanced twice and checked the bolts for torque. I have not done anything to damage the drive shafts so i dont see them being the issue so i assume its a frequency thing with my new setup.

Antonio5664

Take front shaft off and drive it and see if u notice a difference

Mark Doiron

If you decide it's not the DS after pulling it, here's a checklist to help solve the issue. I had a similar issue with my Jeep and it turned out to be the ball joints (so ignore those folks who tell you only rotating parts can cause shimmies because though technically they are correct, non-rotating parts can allow slightly out-of-balance rotating parts to vibrate that would otherwise be fine if the non-rotating part wasn't worn).

https://www.jk-forum.com/forums/jk-w...obbles-260145/