Hey guys I recently purchased my first CJ and stay glued to this forum all the time. But I can't seem to really find my exact problem when i search. So maybe someone can help?

I have a 2000 xJ classic 4.0 auto trans 4wd. 2" rustys bb on 30's.

My first issue is with my new belt.
I replaced my old one it was in rough shape. I got the new one and it was waaaay shorter than mine. I took it back and the parts store said the part number from my old belt was from a postal service jeep .... what??

Not taking his response too seriously I got the second belt and it as the same length as my old one so I put it on. Now sometimes when i start it the belt squeals. Does it just need to break in a little bit? Is this normal for new belts?

My second issue is I'm getting a whistling/high pitched howl from my front end when i get up to around 40mph and during deceleration. It does not do it at all during idle. I don't think its the wheel bearings because cornering doesn't effect it and it doesn't growl or anything. Its just a loud whistle type noise. It could be from the engine, but im fairly certain its more the front end. Any ideas? Or could it just be a usual jeep noise? Any help would be greatly appreciated and forgive me for my noobness. I don't have alot of spare time to really inspect it here lately I work for the sheriffs department and we've been getting alot of overtime. Its my DD and I really love my jeep and want to try to keep it running top notch.

Thanks guys.

 

for your belt squeak i would check the tension. a loose belt will squeak a lot. and for the high pitched noise in the front end, i would get all 4 wheels off the ground, put it in 4hi and accelerate until the noise is present and then have someone check the differential with a stephescope to see if thats the noise. or you can listen while they accelerate of course. keep us posted man

 

Thanks for the info man. Whenever i get the time ill check that out. Any idea what the whistle could be if you had to guess?

 

The serpentine belt on the 4.0 needs to be awfully darn tight to keep quiet. Tighter than any other engine I've had. I usually have to tighten mine a bit after the first 30 minutes of running as they can stretch a tiny bit.

Do NOT use belt dressing on it!! That stuff is reserved for old v-belts, not serpentine belts.

Try tightening it a smidgen. If you're unsure as to how much, I recommend the Krikit II tension gauge.

The whistling noise is hard for us to help you with. Try to narrow it down a bit more if you can.

 

Just a rough guess on the whistle knowing jeeps and working at a shop where I've seen it. It could be a bearing in the fron differential assembly. It would take some pinpoint test with the wheels off the ground and the jeep being accelerated in 4wd to the speed at which it makes the noise

 

Whistling noise could be slipstream going through body panels/grille.

 

Always watch when buying a new belt. I believe it is Oreilly's that the first belt listed is for a RH drive. Sometimes they look no further.

 

Thanks for the info guys I really appreciate it. Belt hasn't squealed at all tonight. Tomorrow morning I'm gonna get under the hood and see if i can tighten it up a bit

 

As for the whistling, sorry if my description is vague but its really all I can say to describe it. Its not running weird everything feels tight on it it may just be one of those little common noises that just seems uncommon to me because its my first jeep? Haha

 

Whistling isn't common. Mine doesn't whistle at all. (Not even for the ladies)

 

'95 XJ 4.0---no whistle. Any chance it's leaking coolant/ steam from somewhere? I know it's dumb (it would overheat, of course) but I can't think of too many things that would cause a whistling noise.

 

My uncle has a shop in town I'm gonna take it to him tomorrow and see if we can figure out what's going on with it.

 

I call it a whistle, but it's actually somewhat of a really high pitched hum. It starts once I get up to around 40 and continues during deceleration until I stop then it stops.

 

Does sound like a bearing

 

A wheel bearing?