okay, so this is for my buddy who has a 96 taco with the 3.4 and auto.
This problem is intermittent...maybe every 7 or 8 starts.
meaning, when you come to a stop at an intersection, or wherever, and then when you release the brake, there is a "thump" that you can feel that is coming from the rear of the truck.
it does the thump before you even get on the gas.

we have checked the driveshaft and the universal joints on both ends...cant seem to find any play there.
The rear suspension is leaf spring and there doesnt seem to be any issues there either...everything seems to be attached to the axle well and all.

we have tried a couple of times to lay on our sides, next to the truck and looking underneath, while another comes to a stop beside you and then takes off....but because it is so intermittent, we have yet to see the problem while doing this.

ideas?

 

How is the arch on his leaf springs? Does it happen more on a hard brake? Any bouncing on a hard take off? You checked the drive line...When was it greased last?

 

the arch appears to be fine and to be uniform. Cannot see any cracks in any of the leaf's, but might look closer...

it doesnt seem to happen on a hard brake anymore than on a soft one
So far as bouncing on hard take off goes...it happens before the gas is even applied...as soon as the brakes are released.
Driveline seems fine, everything is greased.

thx

 

My 4runner does the exact same thing! When I was out searching for my future ride, and eventually bought my 00 4runner, I test drove tons of Toyota's. Almost every single 4runner I drove did this. So, I came home and did some research. I found out that it is the slip yoke on the drive line. I can get mine to go away for a month, by greasing the splines, and then I have to grease it again. It is alot worse in the winter time when the grease is thicker. I've heard people pull the drive line apart and clean the splines, but you have to be careful not to damage the coating.