Mysterious Clunk

[85Silverado]

ok....just took emissions and passed with my '78 3/4 2wd...but left the place with a problem....soon as i put it in gear and just after I take off and apply the gas there's a clunk that seems to be coming from the frontend or under my feet...I can feel it on the floor and in the pedals when it does clunk and it's only one clunk. It's not a rapid succession of clunks. It does it occassionally while driving down the road but always when taking off and sometimes when i change into second and press the gas again. It won't do it if the truck is standing still and i rev the engine in neutral so I don't think it's a motor mount. I got home and bounced on the front end of the truck cycling the suspension and nothing, no noise besides some squeaking. What do you guys think...any info would be appreciated.

[Russell]

Check to see how tight your shocks are Thats what my clunk was anyways...

[85Silverado]

I checked that too...I grabbed the shocks while i was under there and they didn't budge, but they do look pretty crappy, they might need to be replaced.

Also, i don't feel the clunk through the steering wheel if that helps in the diagnoses.

[greg0380]

For what its worth I'll give you my experience with a clunk. For years I had one similar to yours. I thought the motor mounts were ok, got to the point where I got so POd I brought it to a shop to take a look at and they couldn't find anything (PS - I asked them to check mounts).

Years later, I pulled the motor and found that bolts where loose onthe engine stands. Tightened em up and was clunkless.

[85Silverado]

Well, checked all the engine mounts and bolts and tranny mounts and bolts and everything was tight. Checked the steering linkages and nothing. Still can't figure out where it's coming from. Well, gonna continue the search tomorrow. Thanks for the info and ideas on where to look.

[plumbcut]

check control arm bushings, if they are very far gone, it will clunk just like you described..

pc

[MylilBowTie]

That would lead me to think universal joints, carrier bearing (if 2 piece driveshaft), rear end play (backlash) or a cab mount possibly and one more that's kind reaching really hard might be sticking brake front or back.

[trailwart]

im not sure how a 2 wheel drive front end is set up, but on my van i had a clunck and found it to be my sway arm bushings. the sway bar was slapping the inside of the bushings.