Mikeb44

ive just recently put a brand new rough country 3in lift with rear leafs on my 83 sr5.but now around 2000-3000 rpm and in 2nd and 3rd gear there is a bad vibration that i can stand. I cant for the life of me figure what it might be!! Any suggestions?

Lons81

iTrader: (2)

If you dropped the drive shaft, you might drop one end and rotate it 90 degrees. Maybe be a balancing problem.

Mikeb44

ok that makes sense is there any marks or anyway i would be able to tell if i have it in the right spot

GranVille-4crawler

not unless you marked it before you dropped it. but hey, theres only 3 other positions it could be. also check your Ujoint. could be going bad

4Crawler

iTrader: (3)

Yes, try the different positions on the flange and also check the u-joint phasing:
- http://www.4crawler.com/4x4/CheapTri....shtml#Phasing

And some other things to look at:
- http://www.4crawler.com/4x4/CheapTri...FixingProblems

Not sure if you have a u-joint or CV shaft, but different causes of problems and solutions depending on the setup you have.

BMcEL

Sounds to me like the pinion angle is changing due to axle wrap under acceleration, putting the u-joints out of phase and causing the vibration. Otherwise you'd have vibrations while cruising as well.

4crawler's the man when it comes to Toy info...check out his site. Sounds like some shims are in order.

GranVille-4crawler

He meant me of course... haaaaa

uglymudder

if you didn't drop either driveshaft, and honestly I can't see why you would've had to drop either shaft, then the problem is most likely caused by the pinion angles changing. With most vehicles, you start to see that problem with a lift of about 3 inches or more. You could try to put shims in the rear to correct it out back, and maybe look into getting a double cardan ujoint front shaft. can't shim the front because you'll throw the steering geometry out of whack...basically, it won't want to return to center as voluntarily as it does when you're driving now. If you did drop the shaft(s) then you might be able to look on the companion flange where the shaft bolts to the yoke, you might see the old outline of where it was connected originally. Did the kit come with spacers to drop your transfer case? I'm not sure if it's necessary on Yotas, but almost every other vehicle I lifted came with the spacers, and it does help to correct the angle. On a side note, do you have that push/pull drag link steering setup? I only ask because I plan on lifting my 81 about 3 or 4 inches this summer and I do NOT have power steering...I'm worried that if I have to install a dropped or extended pittman arm, I'll lose leverage-meaning harder to turn the wheel. Good Hunting!