Brief Rattling sound when letting off accelerator (1 Viewer)

[SOCAL_FJ60]

1995 fzj80. Happens intermittently, usually in 3rd or 4th gear. It’s subtle and rattles for a second when I take my foot off the gas. I don’t have heat shields on my exhaust. Doesn’t happen when revving it at a stand still. Any idea what causes this? Front u joint?

 

[LandLocked93]

From where is the sound coming? Front/rear? Left/right? Underneath?

 

[SOCAL_FJ60]

From where is the sound coming? Front/rear? Left/right? Underneath?

Front, underneath I think. Hard to place it.

 

[tmxmotorsports]

Do you have a lift on the truck?

 

[SOCAL_FJ60]

Do you have a lift on the truck?

Not yet. Next week . Just got it so baselining it.

 

[LandLocked93]

Yeah, suspect the front shaft, either u/j or yoke. Try greasing them up and see what happens.

 

[RC51]

Had exact same problem, some fresh grease resolved it for about a year.

Yeah, suspect the front shaft, either u/j or yoke. Try greasing them up and see what happens

 

[OffRoadScott]

As recommended earlier check the grease the u-joints as needed. Do not over grease the slip joint, read somewhere on here it can cause a hydro lock and not allow the slip joint to do its job.

Also, I would check your rubber cushion that hold up the exhaust, when letting off the gas it could be allowing the exhaust to sag and rub/rattle against the frame. I believe the rubber cushion are $10-15 ea.

You can find them using this PN:

1756717010​

 

[ceylonfj40nut]

^this plus check exhaust y-pipe bracket that ties exhaust to bell housing.

 

[clx16]

As @OffRoadScott said but look at the muffler touching the driveshaft. Once I replaced the mounts he indicated the rubbing(sounded like a woodpecker) stopped.