I can't seem to get rid of it. Had new joints put in and had the shaft balanced . Had the pinion bearing checked for excessive play. The only thing about it is that it only seems to do it while decelerating while the vehicle is loaded, and it doesn't happen unloaded. It never does it any other time ! I put new mounts on the trans and the engine . It never happens when acceleration just deceleration. HELP . Don't know what to replace next. I have a 94-Runner 3.Slow 5 speed. no lockers or limited slip diffs. Anyone got any idea's ???

 

Two things to check:

#1 is play in the slip yoke, grab it and push/pull and see if any play is felt. Can cause vibration under light load since it is free to move around then.

#2 is u-joint operating angles: http://www.4crawler.com/4x4/CheapTri...l#Measurements

Could be the pinion is tipped down too low, under load the pinion will move up a bit due to play in the bushings and control arms, making the angle better. Under decel, it tips down a bit, making the angle worse. To fix on a coil sprung truck, you would need adjustable control arms: http://www.allprooffroad.com/index.p...ask=view&id=45

This may be the case if you have a suspension lift on the truck.

 

You know I was thinking of using those arms from ALL-PRO but at the same time I was thinking of changing my rear suspension to leaf spring instead of coil spring as the coil spring is so limitingit it so limiting. For the price of the adjustable arms I suppose that I would be better off to spend a little more and just put on the leaf springs and be done with it. Do you think that would solve my vibration problem?

 

If your vibration problem is due to the driveshaft flange alignment (or lack thereof) then correcting the alighment will indeed help reduce the vibration. Another factor that can come into play is if your overall driveshaft angle is getting into the 12-15 degree range, then you may find that no amount of aligning/balancing/etc. will help. In that case, you have just exceeded the limits of a single-cardan shaft and probably would be better off with a double-cardan (CV) shaft.

 

Thanks for your help 4CRAWLER it is going to prove invaluable.What are your views on the coil spring to the leaf conversion?

 

Sort of depends on the lift and the intended use of the vehicle. Coils will give a better ride on the road. Leaves work better for taller lifts and for harder off-road use. Either setup can be made to work, but the coil cost can run up fast to make it work well say at 4" and taller. Adjustable links, panhard brackets, then reinforcing the brackets when they tear away from the frame and axle, etc. may be needed, at least trying to use the stock mounting points.

 

Thanks for the advise 4CRAWLER, seems to me i should go with the leaf spring from ALL-PRO. What do you think ?