Vehicle: 88 Toyota pickup, standard cab, 2wd, 4 speed manual transmission. All stock.

Problem: Drive shaft/ rear end vibration, would consider it to be excessive and unbearable. Starts at 35 mph and gets worse the faster you drive. Loud whining above 35 mph when engine braking.

Attempted fixes so far :#1 Stock drive shaft was dented, had a very reliable drive shaft shop build me a new shaft from scratch. Was told the oem shaft cannot be re tubed because the ends are tapered. New shaft uses standard American u-joints with clips. Made no noticeable difference.

#2: All 4 wheels rebalanced/ checked for damage made no noticeable improvement.

#3: Purchased and installed new third member from Marlin Crawler/ new wheel bearings and seals. No noticeable difference.

#4: Checked pinon angle. Appears to be in spec.

I am still scratching my head wondering why it is still vibrating.
While I was lying on the ground thinking about it I noticed my left spring pack looks nothing like the right side spring pack?
It seems all of the individual springs have large gaps/bend the wrong way compared to the right side???

Could this be causing a rear end vibration??

picsss
Left side









Right side

 

Rear output or drum brakes. Check both.

:wabbit2:

 

output seal/bearing maybe just a loose pinion nut on transfercase? Dang it wabbit beat me by less then a minute.

 

Being 2wd = no transfer case......
The third member was built/assembled by marlin so I assume that the pinion nut is torqued to spec. There is also no play in the third member where the drive shaft attaches to it.

 

You have a rear output that spins your rear dshaft.

:wabbit2:

 

yes I do, but there is no nut there? The drive shaft slides over top of the out put shaft. The piece that slide over the out put shaft is 6-7 inches long and allows for play when the rear axle moves up and down. I believe the 4wd shaft has this in the middle of the shaft. My drive shafted is a one piece fixed unit. Only moving parts are the u-joints.

I adjusted the rear drums. seems to help a little but still lots of vibrating at higher speeds.....

 

Rear output has a shaft, bearing, seal and if worn or damaged can cause vibrations.

Moved to 2WD section.

:wabbit2:

 

there seems to be a little play in the out put shaft. So it seems the soultion is a transmission rebuild?