97 Xj 160k miles. when im driving in the "Drive" position and i slow down when coming to a red light and it shifts down into 1st gear u can hear and feel a clunk coming from the rearend and driveshaft. Now its always been like this, it sounds and feels like the the rear end has some play in it cuz it moves both ways just a little little bit when sitting still,(at the yoke) i can move it back and forth just barely. so when im coasting to a stop it hits second a clunk/pop comes from it. just wondering if this is something i can fix or normal. has new pinion gear. and no locker or posi. its ALWAYS done this.

 

and its the 8.25 rear end

 

bump

 

Anyone?

 

did you check your u-bolts for tightness,check your tranny mount also make sure its not ripped or split in half.

 

how much does the driveshaft move when you twist it?

 

U-bolts are tight, tranny mount is in "OK" condition, it doesnt move or anything, im about to get another mount. The driveshaft turns about an inch with it sitting still.

 

would it be ok to buy an aftermarket polyurethane tranny mount? cuz i bought some poly motor mounts and had to go back to factory cuz they lifted my engine an inch and they were solid mounts and vibrated the entire car like crazy. would the tranny urethane mount do anything like that? or just get a factory tranny mount?

 

U-Joints maybe? mine makes the same Clunking noise.....the 8.25 Rears has a pinnion bearing issue.

 

Try lubing the slip joint where drive shaft connects to the tcase, that should fix your noise.

 

I've replaced the pinion bearing twice, its always done it. only when im putting the brake on to slow down for a light and it shifts down into first. only when it shifts down into first. also, u-joints are brand new, put in last week.

how would that fix it if it has play in it? its my rear end, not my driveshaft. the rear end has play in it. if u take the driveshaft out while its in park, or neutral whichever, the 8.25's yoke has about an inch of play in it back and forth. i know thats why it clunks when it shifts down into first.....just wondering why and if i can fix it.

 

Well if you are positive that it is the rearend, the options are rebuild, replace. To eliminate the play you need to tighten up the excess backlash , this needs to be done by someone with exp. to set the correct pinion depth, preload ect. I still think u would have other issues if the rear axle was the problem.... any gear noise, brg noise at highway speed?

 

I have the EnergySuspension poly motor mounts they use the stock clam shell,as far as my tranny mount its a new rubber one

 

it HAD alot of gear noise going down the road then i went to a buddys shop and they replace the wheel bearings, pinion bearing and checked my shafts and everything else in the rear end, its been fine since but has always made that popping. its not a super loud clunk, just noticeable cause it jerks it. it did it when it was all stock (no lift or tires). it doesn't bother me but i figured it would have messed something up by now..... i'm going to put an aussie locker in it here in a few weeks.

 

did you get anymore engine noise than u had before? i just want better mounts but the same sounding vibrations from the engine.