1999 Ford Explorer Clunk when slowing down

ROBERTMOORE934

MEMBER
1999 FORD EXPLORER
4.0L
V6
RWD
AUTOMATIC
243,155 MILES

Hello,

For a while, I have been experiencing a clunk when slowing down.

The clunk only happens when applying the brakes, and it only clunks when it slowed down to around 20mph(between 1st and 2nd gear). The front brakes and wheel bearings have been replaced, no trouble codes, and front suspension has no problems. The rack is a little slacked, but thats about it. It also has a rebuilt transmission with recent service. The rear brakes are original(never had pads or new rotors). The U-Joint is in good shape. It does have the original fuel pump too. The rear differential has been serviced.

2 Replies

DOCDTC

MECHANIC
53 POSTS

Hi.
Is it a single clunk you hear? And do you hear it when the trans actually downshifts or just at that speed? If it is a single clunk and occurs at the downshift, block wheels, engine off, with transmission selector in neutral (not park). Now grab driveshaft and check amount of freeplay when rotating back and forth. There should be no more than 1/8" of rotation present.
Youm also did not mention if you have checked lube in rear differential, when downshifting at lower speed there is a slight hesitation that causes an unloading of the ring and pinion gear, and either excessive play or low lube can cause this to be an audible clunk. Hope this helps, Doc