Clunk on acceleration
 

2002 F-250 Crew 4x4PSD 4R100 178,000 miles. Original owner.

When accelerating from dead stop, I get the all familiar clunk. I do not get the clunk in reverse, and if I begin to roll then give it the gas the clunk is much less or not at all. WHatis very strange is in the cold, it is not noticeable.

What I have done.

1) All u-joints. The OE joints still looked pretty good, of course you dont know that unless you tear them down...so why not just replace them.

2) Grease, grease, grease slip joint

3) Changed diff oil....very slight silver in bottom...no metal and the ring and pinion look very good.

4) Also checked drive "slop" and it is within Ford specs.

5) Trans serviced regularly....very little metal in there too...only on magnet/plug.

I have not checked u-bolts on rear diff yet, but other than that I am out of ideas..

Ideas of what to look for next?

Body mounts?

Do you hear it on hard stops?

They look good. I never checked torque, but they appear tight.

Nothing on the stops, only acceleration....Wait, if I come to a full stop then rock it I feel a little bump....hmmmm. So, what would that mean??

Could be body mount bushings are worn out. I've read threads in the Excursion forum, but not sure if it is applicable for crew cab. The front between the two is almost identical.

Do you feel the clunk right below you on the driver's side floorboard? Does it clunk also when you turn into the driveway?

Double post...oops.

Have to be honest - I am not familiar with the SD front suspension. But my girlfriends contour recently has a noticeable problem with the bushings on a shock support. I had a similar problem with a blazer sway bar bushing - clunked on hard acceleration and hard braking - so annoying. Just saw your posted and thought I'd mention it.

Engine mount rubber might be stretched.

Sway bar bushings will make a pretty hard clunk when stopping and taking off when they wear.

I had that exact same noise\feeling on my solid axle '94 F350. My ball joints were sooo bad they were oblongating the holes in the front knuckle on the drivers side. Performed the repair now all is good.