I just finished doing a 3 inch lift on my jeep. I had some vibrations pretty badly. I put a 1 inch transfer case drop on and still have very little vibration at take off. How does this drive shaft angle look?
The angle looks pretty good to me, way better than mine at the moment. But I can see why you might get some vibes at take off. As you take off, the pinion moves up, therefore causing your vibes.
It seems like you are trying to align your DS like a CV DS, which is wrong. This is what the proper way of setting up a conventional two u-joint DS should be like:
The axle yoke needs to be at the same angle as the transfer case yoke. It should NOT be pointing at the transfer case yoke unless it is a CV driveshaft.
It's hard to tell from pictures. You need to use an angle finder to find out your transfer case angle and you need to use that same angle on your axle yoke.
A 3" lift will pull the driveshaft out of the slip yoke some on the transfercase. This longer driveshaft will have some loose motion on the splines. This was causing me to have vibrations on start off. I replaced my rear axle with a D44 which actually shortened the overall driveshaft length some and most of the vibration went away.
You shouldn't live with any vibrations. The vibrations are being caused by u-joints that are being run out of their design parameters, and continuing to run them like that will ruin u-joints fast (best scenario) or worse, can start taking out seals and bearings in the t-case and/or differential.
It's pretty easy to remove the 4 nuts on the bottom of the t-case skid, support the transmission, then remove the 6 bolts holding the skid to the frame. That will give you a good look at the mount. Before you do that, you can put a small pry bar between the back of the skid and the transfer case and see if you can lift it. If you can, the mount is definitely bad, but even if you can't, it still could be partially torn or rotted enough to be a problem.
Well? I crawled under my jeep today and took a good look at the transmission mount. Sure enough? It's ripped. I have attached a picture. Do you think this could be the cause for the slight vibration to take off?
Yes it is most likely the whole reason for your vibration. The torn mount allows the transfer case to move laterally when torque is applied on acceleration, then settles back to it's normal location when the load is less. Replace the mount and it will likely solve your problem.
most certainly. allows the whole drive line to move and tweak the u-joint parameters until they settle down during flat speeds. did you get a chance to check your motor mounts while you were at it?
on most cars btw, a broken motor mount would lead to a broken or cracked exhaust manifold/header. however, the hanger by the cat is hung off that tranny mount. BE ADVISED
Check your transmission mount. When I did my 3.5" re short arm kit, I ran no tcase drop and no cv ds for a week while I ordered my cvds and I had a violent shake on take off due to a bad transmission mount and the bad pinion angle just magnified it to the point where I noticed it. I replaced it with a poly mount but if I had to do it again, I would've just bought another stock mount. The poly one has vibrations out the @$$ at idle
I replaced it with a poly mount but if I had to do it again, I would've just bought another stock mount. The poly one has vibrations out the @$$ at idle
I still have a slight shimmy at take off. I think I may know the reason. When I replaced the bolts in the upper rear axle links, I put in some 3/8 bolts. Thinking back, I think the original bolts may have been metrics. I believe the metric bolts had a slightly larger diameter and 3/8 bolts. Could this cause slight movement in my rear upper control arms at the upper axle links? Could this cause the shimmy?
Not sure where you put undersized bolts. If they were in the control arms, yes...take them out and replace with proper size grade 8 bolts.
If you're talking about sway bar end links, they use a shoulder bolt, and using the wrong bolt (under sized) may make a clunk sound as your suspension flexes, but wouldn't cause a vibration on take off.
My advice would to be get the right bolts for everything, torque them to spec, and take it for a drive. If you still have vibe after that, try a couple of washers between the t-case skid and frame at each of the 6 bolt locations.
Really irritated at this point? I've already done a 1 inch transfer case drop. Should I try removing the transfer case drop now that the rear axle is tilted correctly?
Is it possible that the transfer case drop could be too much? It was 1 inch.
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