Cannot Diagnose Clunking!!

[brianp007438]

Hello Explorer people, I'm a long time reader, 1st time poster.

I have a '94 Limited 4x4, 195K miles absolutely stock.

I just got done with a (mostly) complete front end rebuild brought on by an awful clunking prevalent during harsh road conditions. I knew my LH lower ball joint was gone, the wheel could be wobbled when off the ground. I installed 4 new Moog balljoints (thanks to Ted J. for his write-up) along with new RA bushings, sway bar link bushings and axle pivot bushings. The steering system seems too tight for this sound and I'm not feeling it through the wheel. It is at it's worst when I'm driving uphill and it makes almost a bobbling, clunking sound that can be felt through the floorboard. Everything under the vehicle feels tight and I can't grab an' shake anything to reproduce the sound! I've been searching and searching but I can't find a viable solution to this issue. What could have come loose under my vehicle? Ant suggestions are very much appreciated. Thank You,

Brian P.

 

[mmbretts]

u joints?

 

[MrShorty]

It is at it's worst when I'm driving uphill and it makes almost a bobbling, clunking sound that can be felt through the floorboard.

Any chance this is in the engine rather than the suspension? These engines are prone to "ping" (spark knock or detonation), and driving uphill is the usual situation when it is worst.

 

[thunderhorse]

Thinking tranfer-case not really out of 4WD

 

[brianp007438]

Is grabbing the driveshaft and wiggling, jerking, and otherwise manhandling it an effective method of testing worn U-Joints? I've done these things and the driveshaft is absolutely tight when under the car with the parking brake applied. As far as pinging goes, I have dealt with the loose intake manifold bolts/pinging that occurs as a result, situation. I know this sound is not pinging. It occurs under very light through heavy acceleration, but almost never under deceleration. Intensity always stays the same. Could this be the rear trans mount? The transfer case knocking into the floorboard? I didn't notice any rubbing, but I'll be crawling around there tomorrow for sure.

 

[Vargas]

Were the RA bushing brackets in good shape? If the previous RA bushing were in really bad shape, the openings in the brackets will get enlarged and allow the new bushings to shift around.

 

[backfrmcolorado]

Were the RA bushing brackets in good shape? If the previous RA bushing were in really bad shape, the openings in the brackets will get enlarged and allow the new bushings to shift around.

very true... i have that problem now. just even a small bump in the road gives off a ping noise. it took me forever to determin my problem seeing as how i did almost everything that you have done. i even put on all new steering parts. turns out even with new RA bushings the brackets that holds the RA and the bushings can get egg shaped and all that does is cut right thru the new RA bushing. take a look under there and see.

my task this weekens is to put new RA brackets on... only $65.00 at Autozone.

 

[brianp007438]

Sometimes it's the simplest of things...

...That can confound!! I have just replaced the RA bushings, (which are this Explorer's third set) and the bracket holes were in great shape. I really only replaced them because they're cheap and I needed to have the radius arms out anyway, since my front diff was leaving a mess everywhere I parked the truck. I had a sneaking suspicion there was a drivetrain issue here, since the clunking was proportional to throttle input. Sure enough, removal of the 4 bolts that suspend the skid plate under the transfer case revealed my problem. The plate was pretty bowed, and the transfer case was smacking the skid plate in relation to the drivetrain twist. So I rolled over the skid plate with my front tire a few times and re-installed. Bingo!! No more clunking and general vibration is now greatly reduced! It's like a new vehicle now that the engine/trans/TCase is again insulated from the frame and body. Not sure how the skid plate got so bent... I almost never take this Explorer off road. Now if I could just figure out that rattle under the dash...

Thanks for all the help!

Brian P.