Clunking while driving

[BillM]

Occasional clunking while driving. Coming from just behind cab. I've changed out the driveshaft and greased the rear spring bushings. Sounds like a 12" steel bar banging around, can't find anything loose underneath. 

Any ideas?

Bill

[datzenmike]

Most likely:

 

Loose exhaust pipe, broken clamp/hanger. Muffler bumping body.

 

 

Going over bumps or turns?

 

Spare and jack secure? Broken or loose shock? Broken coil spring? loose lug nuts? Hatch not adjusted properly.

[DwayneOxford]

Check ball joints.

[datzenmike]

5 hours ago, BillM said:

Occasional clunking while driving. Coming from just behind cab. I've changed out the driveshaft and greased the rear spring bushings. Sounds like a 12" steel bar banging around, can't find anything loose underneath. 

Any ideas?

Bill

 

Won't have been the drive shaft. U joints can make noise, usually a squealing sound and or vibration, sometimes a clunk when engaging clutch on take offs but if drive shaft replaced I assume the U joints would be new also. 

 

Grab the exhaust pipe and really shake it HARD. Does it or the muffler hit anything??? Now do the same to the shocks. Don't pull the car down on top of yourself. Climb up on the bumper and bounce the rear of the car. Anything? 

[BillM]

I'll check it out in the morning 

Thanks for the suggestions

Bill

[DwayneOxford]

Got a friend, had '83 reg cab 2wd that was making a clunking noise that we couldn't figger where it came from. Figgerd it out when the ball joint came loose. Was a job getting it on tow dolly.

[BillM]

Well-I pulled the bed off of it today and drove around a bit. Totally quiet, no creaking. Put the bed back on and creaking started again. I'm guessing that it is the pads creaking. I think that I will make up some new pads and see if I can make it quiet.

Bill

[ggzilla]

What about the clunking? Just tightening the bolts should fix that, unless it is a spacer that has compressed too far

[BillM]

Ok, I'll try that but they are already pretty tight

[ggzilla]

if i recall correctly, some of the body fasteners just use a shim between frame and bed. Those just tighten. But there are a couple that have round poly spacers, and those might have disintegrated, or more likely compressed down too far

[datzenmike]

You didn't say if random or when hitting bumps.

 

Grab the box and rock it side to side. Jump up and down on the bumper or inside the box. Try to replicate the 'clunk' and locate it.

[BillM]

Well, it seems to be fixed!

Greased all of the fittings on the front suspension and magically all of the squeeking and clunking stopped. I'm guessing that the truck hadn't been greased for about 30 years from the condition of the plugs hiding the greasing holes but it now drives as nice and quietly as a new truck.

Billm

[DwayneOxford]

15 hours ago, BillM said:

Well, it seems to be fixed!

Greased all of the fittings on the front suspension and magically all of the squeeking and clunking stopped. I'm guessing that the truck hadn't been greased for about 30 years from the condition of the plugs hiding the greasing holes but it now drives as nice and quietly as a new truck.

Billm

Better check the ball joints.

[ElliotV]

wouldn't hurt to take a close look at the ball joints for sure and check for tears in the boots, they really aren't hard to replace and are cheap enough

[DwayneOxford]

16 hours ago, ElliotV said:

wouldn't hurt to take a close look at the ball joints for sure and check for tears in the boots, they really aren't hard to replace and are cheap enough

A friend's 720 was making that noise. It went through frame, couldn't figger source. Was dang hard to get on the tow dolly with ball joint failed and wheel flopping around. Fortunately he had just made a doubleback right turn and was going slow.

Edited September 15, 2025 by DwayneOxford