my 1989 pickup makes a clunk sound when accelerating from a stop. mostly happen the first thing in the morning, and it gets better but does not totally go away as I put in 15miles of stop and go traffic. clutch or u-joint? i'm thinking u-joint.

 

I'm guessing its a manual trans, Check u-joints first and then if there are zert fittings on them then grease um up and see what she does. Good luck I hope its a simple fix.

 

Other things to check are engine mounts. Then suspension parts/bushings etc. I think the driveshafts and engine mounts are more likely but check everything.

 

so ive crawled under the truck and checked out all of the u joints on the draveshaft. all of the joint except one seem to be fine, ie no play by hand. the suspect one (closest the the rear diff.) had a tiny bit of play in one direction. this amount of play was able to give off a clunking noise by the way.

my question is what is the acceptable amount of play to we within factory spec. for u joints? is my suspect u joint within spec? is this a must repair now? what can go wrong if i dont.

thank in advance yotatech.

 

U-joint or wrong wheel lug nuts.
I've had both problems.
Both my a very similar click/clunk sound.
The wrong wheel nuts make a ridiculous pepper grinder noise going around corners.

 

Good thought with the lug nuts. More likely to be a problem on alloy wheels.