driveline psychosis (1 Viewer)

[duckling]

I've had driveline vibration for some time. Rear diff rebuilt to Toyota 3 years ago. Tighter, but feels a little rough at the flange, compared to the front, which has more rotational play, but is silky smooth. New u-joints. I'm thinking it's the TC. With the rear driveshaft off, I can rotate it quite a bit. If I wiggle the flange back and forth, it feels as if something is loose (before it meshes with the gears). Can there be this much play in the gears? Can the flange become loose while the nut is still staked? It's all japanese to me…Hate to blow it up for ignorance. The vibration is of two sorts…loud at 60 to 70 mph and a waah waah waah over about 50 mph. Thanks for any wisdom…

84'BJ60 229km

 

[Front Range 4x4]

Have you checked the driveshaft itself? Unbalanced or not straight will give those type of vibrations.

 

[roscoFJ73]

Hi Duckling I had that waah waah waah at 50 mph. It went away after the engine swap when I changed to a diesel gearbox and rebuilt the t/case.
It turned out the diesel gearbox was bad and had to be rebuilt but at no time was the waah waah present

Did nothing to the driveshaft or uni joints.
I had the diff done recently but that was more of a constant drone.

 

[CodeRed]

Not to hijack, but I think I'm experiencing a similar problem.

I just had the engine changed in my 89. After the reinstall of the new 3fe, right at 2000 RPM and not all the time but semi-freequently (does any of that make sense?) I get a HUGE vibration, like running over those wake up strips on the side of the interstate!

It stays until I nail the throttle which will put it up near 3k or drop down a gear (automatic).

Any ideas?