I've got an issue hoping someone can help with. The other day I was driving my xj and all of a sudden started getting this serious vibration in the drivetrain. It only vibrates between about 35-50 mph. Also, it only vibrates under light acceleration, like when giving it just enough gas to maintain speed. When I give it more gas, like trying to pass it fades out. It's really more of a shudder and feels like it's coming from the rear. It was lifted when I bought so I don't know if that's the issue. Don't think so since it suddenly started. Just looking under the jeep, everything looks fine.
Thanks for any help.

SW

 

Almost sounds like you have had a bearing go out brother, take it to a tranny shop. They might tow you for free (towing recommended) if you have stuff going out its nothing to mess with. Tranny shop would be able to give you the best answer.

 

Have you checked your driveshaft U-joints?

 

What are your driveline/pinion angles? Do you have SYE? U-Joints good? Tires balanced? Any humming or groaning?

 

Just went out and looked at things again. The u-joints seem solid. There is no play in the driveshaft at all with it in park. The PO says it has a 4" lift but I'm not sure. Looks more like 2.5", but I haven't measured it. Reason I say that, the driveline angles look ok, not much angle at all really. And no it doesn't have an SYE. Hope to fix that one day as well. Not hearing any groaning or anything. Could be the tires maybe, just had them put on a couple weeks ago but one could have thrown a weight.

adkodak- which bearing are you talking about? wheel or pinion?

 

Ok, one more question. Is there a way to check the wheel bearings without taking the wheel off? I was thinking maybe jacking it up and seeing if the wheel moves side to side at all. But not sure if this will really tell me anything.

 

Without being there I couldn't tell you what bearing could be doing it. I know there was someone who posted a similar event a few weeks back and it was a crankshaft bearing.

Once again it sounds like a minor nuisance that could become a big problem. I'd at least take it to someone who deals with the issue on a more daily basis and get a free opinion. It never hurts. Most of them will give you a little lead cause they want you to trust them to fix it.

 

Mine does this SAME thing! Between 45 and 55. Only under light acceleration/maintaining speed. Hit the gas and it works itself out quick-like. My u-joints have 147,000 miles on them, 3" lift, 1" transmission drop, leaking rear transmission seal but not much - just a drop now and again.

 

Drop the crossmember and check the rubber mount.. Maybe