Yeah, I replaced the trans mount a couple of weeks ago. The driveshaft is at the driveline shop now getting new Spicer u-joints and balanced. They said it should be ready tomorrow. I'll let you guys know how it rides once I get it back in.

 

Hope that works for you. I've got an '96 AWD and everytime it has been the u-joints. I first thought I had fixed it when I found a dry joint in the rear drive shaft. Turn out the vibration was still there. Front drive shaft was tight. Pulled it anyway and found one of the bearing caps had siezed and was frozen on the u-joint. Replaced and problem solved. Careful with the spicers if your running large tires. Normally the u-joints are designed to be the weak link on purpose. Something else will give before the spicers.

 

Thanks. I've heard that Spicers are pretty heavy duty. I'm not running oversized tires, everything is stock, but I'll keep that in mind, nonetheless. I haven't checked the front shaft joints. Hopefully this will fix the shake, but if there is any vibration left after changing this out, then I will check the front u-joint too. Thanks for the heads up.

 

Well, no dice on the drive shaft guys. New u-joints, balanced, and the problem is still there. Didn't even phase it. So, I'm doing what I should have done in the beginning. I'm putting it in the shop! LOL! It may be a week or two, but when it's finished, I'll post the results and let everyone know what the mystery was.

 

If possible I would try another set of tires. Just because they are balanced does not mean they can not cause vibration. I had a vibration at around 60-70 mph, had the tires rotated & balanced. Front end alignment. Replaced front shocks. Still had vibration. I then replaced my tires and the car is smooth as silk at all speeds. The tires were going to be my last resort before I started getting into mechanical items. The tires I replaced still had good tread remaining. This was on my 2000 GMC Jimmy 4X4.

 

YO MIKE i'm having the same problem you are and have replaced everything you have as will and nothing for me either still the same i havent changed the u joints but i dont think thats the problem but as you stated its cheap and could hurt it!! PLEASE DO LET ME KNOW WHAT YOU FIND OUT!! I have been researching this for weeks and nothing but i have seen that one guy said it was the water pump by the way!! Grab the fan and see if you have any play in it!!!

 

Yes please keep us updated. My 92 has been doing this for sometime. Been to 3 shops and a very knowledgeable shade tree mechanic and no one can find anything. Has a shimmy at exactly 70 and up. Didn't do it untill it was lowered. Tires make no diffrence. All balljoints are greased and good, tie rods and all are good, (getting a modified sticker will tell you anything that might even be thinking of going bad.) new moog idler arm, shocks are fine. So yeah, lookin foreward to a post from ya. lol

 

Shake is resolved!! I don't know how much this will help with the others having the same problem, but mine turned out to be a bent wheel. The shop kept thinking it was tire balance, but each time they balanced them, it still didn't work. But, when they rotated the rear wheels to the front, the shake stopped and the front end felt loose, so they knew it was something with the wheels. They finally pulled the tires off the rims and checked each rim, and they found one that was wobbly. They got another one from a salvage yard, put the tires back on and rebalanced and the shake is now gone.

 

Ah damn, er I mean I'm glad you got that shake fixed. I have new rims and tires so I doubt that's my problem. But glad yours was a quick fix. Nothing mechanical, you got lucky lol!

 

how the hell did they NOT find the bent wheel before, with all of the rebalancing of the wheels/tires they did?

if you had of mentioned that the shake moved from your *** to your hands earlier.............i know i would've picked up on that. i know you mentioned that it was in the rear initially, but i don't remember you saying you had the wheels rotated front to back.

either way, @ least you got that issue resolved-and now your truck is almost new again. good for another 10 years.