I've spent weeks searching these forums and others like it to try to figure out my problem and I am at my wits end!

99 B3000, 3.0L, manual trans., 2wd, extended cab.

Problem: One or two clunk noises when accelerating from a complete stop (I know what you're thinking...keep reading). No noises during sharp turns or going over bumps in the road. No noises during braking. No trouble at all with clutch or shifting through gears. No clunking when going through gears, only when accelerating from dead stop. Can't reproduce sound by bouncing or rocking front end of vehicle. If I accelerate slowly enough it doesn't clunk.

Repaired in the last month:
1) U-joints (note: one piece drive shaft, no carrier bearing, no slip splines)
2) Both inner and outer tie rods
3) Wheel bearings
4) Drained, checked for broken gear teeth and filled differential
5) Drained and filled transmission fluid

Checked:
1) Ball joints - good
2) Checked for extra slop in the slip yoke where it comes out of the transmission - good
3) Transmission mount - good
4) Shocks - good
5) Control arm bushings - good
6) Sway bar and links - good
7) Brake calipers and caliper brackets - good

Any other ideas???

 

id check your motor mounts. In my experience they only seem to show problems during acceleration or high torque times. Just an idea

 

The "clunk" is metal to metal contact because of excessive play between the two components.

I know you mentioned checking the control arm bushings but are you satisfied with how they were checked? The "clunk" will not present itself by simply grabbing/twisting them.

This is especially true with the control arm bushings. Try it with a large pry bar and see if you have any movement.

You didn't mention where the clunking sound is coming from? The front or rear?

 

Worn out or cracked leaf springs?

 

Pinion and Ring Gear in the Differential? hmmm.

 

body mounts??

 

Sorry. The clunk at first sounded like it was coming from under the cab, but now I think its more the passenger front of vehicle. I was told to grease the slip splines, but I have the one piece aluminum drive shaft so my yoke and slip splines are in the transmission housing. Wouldn't I end up with problems of the grease mixing with the transmission fluid?

I'm gonna check the motor mounts this weekend.

GMG - I checked the control arms by putting a steel rod under them and prying up. I was able to rock the vehicle without reproducing the clunk. There was no slack in the upper ball joint when doing this either.

Thanks for the replies!