hello got a little problem with my jeep, i have a 3 inch lift with a hack and tap SYE and i have a noice when im coasting, sounds like a grinding tapping noise, doesnt do it all the time and is a lot worse when getting off the highway, doesnt do it when im on the gas even just a little just when coasting to a stop or slowing down, im leaning towards the transfer case chain ( its a np231) i thought at first it was the U joints but now im thinking its that, any info would be much appreciated. thanks

 

grinding and taping sounds more like a bearing. think i'd check front unit bearing, then rear wheel bearing.

 

I wouldnt think it would be your chain, because it shouldnt be moving in 2wd. And thats not something that would only make noise while coasting. Grinding/tapping only while coasting sounds more like gears to me. Possibly one of the differentials?

 

it could be, i didnt have a problem until i put in a new transmission mount, then all of a sudden all these noises came up, my old mount was pretty well worn out so that could have softened the noises. the front end has no ring gear in it, i took it out because i blew it up offroading so the front is just spiders and nothing contacts the pinion gear so the front driveshaft doesnt spin... the rear is a chrystler 8.25 that i got from a local pick and pull.... hopefully that isnt the problem.

 

Have you checked all your fluids? Did it start making the noise immediately after you replaced the trans mount? Or was there some time in between. I dont see how changing the mount could cause any noises like that.

 

thats what i thought too, i did flush the fluid the other day, was kind of a pinkish color like there was water in the t case, however i never had problems until i changed that mount, all i can think of is that the old one was so loose it was absorbing any noise or vibration and the new one is of course stiffer.

 

also id like to add that i did a test today and my front diff was low on fluid, i filled it up but the noise is there still, and i also noticed that it doesnt make the noise, or doesnt seem to anyway, when i downshift manually when i want to slow down. any input?

 

Well I just noticed that you have a 96, so you dont have the CAD. So I was thinking it could be your Tcase. But then I remembered you have no ring gear... haha. So your chain definitely wouldn't be spinning. I'm still guessing its the diff. When coasting normally, the load is on the coast side of the gears (which I'm guessing is where the noise is originating). When you downshift, it may be transferring the load somehow, which could quiet the noise down. Did I mention I'm guessing??Ha. It's really hard to diagnose these things without being able to hear it.

 

I'd lean toward a rear pinion bearing. That's my problem anyways

 

Was yours only making the noise while coasting?

 

Just right off the gas. Not engine braking or anything, just putting a neutral almost decelerating load on it

 

Mine is making noise too and started immediately after replacing the tranny mount. But it kind of a rattling noise and stops if I push the 4 wheel drive handle down. Not sure why that helps but it goes away if I do that. Does yours have a rhythm or is it just a random rattle like mine?

 

Mine is more of a grinding sound. Your's kinda sounds like your t case shifter linkage might be contacting your front drive shaft... if your's actually turned. That is very strange. Possibly a bent shift fork or something in the T case. Maybe your front drive shaft is turning from some unforseen damages to your T case internals. You did say you did something crazy enough to blow your front diff to hell

 

yea same with mine and its worse right after letting off the gas, then goes away then comes back after coasting for a little ways then goes away when almost stopped, its strange.

 

also ill add that i have a hack and tap sye with a front driveshaft on the rear, i was told that the double cardan or whatever which has the ball in it can go bad.... not sure if thats causing my problems either but the u joints seem fine