Front driveshaft noisy in 4wd on the road?

[77cruiser]

I have a similar vibration/noise in my fj40 as well so I thought i would ask. When the 4wd is on and I am driving above 25-30mph the front driveshaft vibrates alot. more so than I think its supposed to and you can hear it. Almost the same noise as Mud terrains sound at highway speeds.
Is there something I need to do to adjust the alignment on them?
62 has about 3.5" of lift and the 40 has 2.5". They are in good shape and do not appear to be damaged at all. the u joints are tight and in good shape as well.
Help is appreciated.

 

[smtyblt]

Is your lift all suspension if so put 3-4 degree shims on top of the spring pack and rotate your axle back up. you have changed your caster and thus taken your drive shaft out of parrallel.

Did this to my old 62 with the OME 2.5 lift and longer shackles I made 6 degree shims and the vibes went away.

It will also drive better and center quicker more caster.

Cam

 

[77cruiser]

cool. So you do put shims in the front too? I was under the impression they were just supposed to go in the back.

 

[77cruiser]

sorry, Yes, lift is all suspension. front shakles are 3/4 longer than stock.

 

[Mace]

front shakles are 3/4 longer than stock.

Ding ding ding..

Get a alignment check at a reputable shop. Bet your caster is out of whack..

 

[Winslow]

Also remember that shims will pull lube away from your pinion bearing. After you shim the truck, park sideways on a hill and 'overfill' your axel.

 

[Mace]

Also remember that shims will pull lube away from your pinion bearing. After you shim the truck, park sideways on a hill and 'overfill' your axel.

Not if they are there to adjust the caster, then they will bring the pinion back to more of a "stock" position..

 

[Overlord]

I'm having a similar problem. It happened when I first put on the 2.5" BDS lift. A 6* shim fixed it. It's happening again since going to a 1" longer than stock shackles. Probably going to go with an 8*

 

[77cruiser]

nice thanks for the pointer on the shim degrees! I will try that out.