So I recently installed a SYE on my jeep to help remedy some terrible drive line vibrations caused from my 2.5" lift kit. After install the vibrations were gone except for when ever I am going roughly 35 MPH there is a vibration that comes on pretty strong, but once I go over 35, like around 40, It dies down but there is still small hints of it. The pinion angle was good, so I'm not really sure what exactly the issue is. Could it have something to do with not properly torquing the output shafts on the T-case, or could it be the driveshaft isn't balanced correctly?
It could be any of those things. What is your pinion angle at vs drive shaft angle? Also double check you have everything tightened back up properly.
I'm not sure what the angles of my drive shaft vs my pinion angle. I'd have to check in the morning. But I'll try to tighten everything up in the morning.
Is the pinion pointing up to the drive shaft like the photo below?
Do you have adjustable control arms?
Do you have adjustable control arms?
If you installed an SYE, then you also installed a double cardan rear drive shaft. And, you also would have installed adjustable rear control arms, well, at least uppers. After installing all of this, you then adjusted your pinion angle so that the drive shaft angle is the same as the rear diff pinion angle. Yes?
Yeah, the pinion is pointed at the double cardan like the picture. And yeah I do have upper and lower adjustable control arms in the rear.
Yeah. I’ll be honest though I did eyeball the pinion angle. Do you think that would be the issue?
Some TJ's can be sensitive to small changes. Put a angle finder on it and see where you are.
So I checked the angles and I was a little high on my pinion. So I corrected it. But the vibration didn’t go away. It was a little better but still there. One thing I did notice was that my axel was a little off center. I’m not sure if that was the issue. I’m thinking I might take out the trac bar relocation bracket that came with my 2.5” lift kit.
That’s what I thought at first, but I took out the rear driveshaft and the vibrations went away.
I guess it is definitely the rear driveshaft then. I suppose it's one of two things then. The pinion angle still isn't quite right, or the driveshaft wasn't balanced properly.
Do you think that it could be that the axel is a little off center from the rear output of the t-case
That seems very unlikely. If that were even possible, it would have to be way off. I'm talking about so far off that you looked at your vehicle from the rear and could say, "Wow, my axle is way off center!".
Still, I'm not going to rule it out. I'd center your axle under there since it should be done anyways.
Willysjeep47
New Member
What driveshaft did you buy? Even my Tom Woods had to be sent back for a rebalance because my Jeep is super sensitive to the rear driveshaft. Having an 8.8 (offset pinion) and a tummy tuck has pushed it to the max.