Wasn't the SYE, what the he!! could it be!?!?!

[Rev Den]

When you say you re-did the U-joints, did you replace them? It almost sounds like you took them apart and re-lubed them, but did not replace them. Any chance you can get it up on stands, apply some brake, and give it some gas? Maybe a brave soul can use a "listening aid" to try to id where the sound is coming from.

Before you all jump on me for suggesting this......

Make sure you use jack stands on a firm level surface

Have room in front of you in case it drops

Have your helper in the truck, you do the listening with a LONG pipe, and a rubber hose to your ear, so if it does fall you are out of the way.

I do not recommend this, but it is an idea.....just be as safe as possable.


Rev

 

[4ward]

Den, we do that all the time with the race car. Nothing like seeing a tire spinning at 140 mph 5" from your face

Ary, I'm still thinking it's a u-joint phase issue. If it's only coming under load, I'm guessing your springs are wrapping up a bit and throwing them out of phase enough to make your sounds.

Oh yeah, if you're going through the pains of greasing the cups in a joint, just replace the darn thing. I thought my joints were good in my rear shaft, did the grab and shake- everything was solid. Now that I have it out of my heep, I can see that it needs replaced in a bad way. Actually, it shoulda broke instead of the 60 shaft on the pad.

 

[Safari Ary]

Well, to clear it up, I replaced all the U-joints. The Heep is at the dealer right now(my parents didn't leave me much choice, they were tired of me having my Jeep in pieces in their driveway which is definately understandeable). The guy just called and insists that I need to put in a T-case drop and that "no, shims won't fix your angle problem." I asked then "what exactly do shims fix then?" He was silent. I asked him to at least look at the fluid in the rear-end and see if anything looks out of the ordinary.

I really didn't think the angle was that far off, and the old u-joints were in pretty good shape(no play or anything, although the grease did look a little burnt? maybe not in so good a shape afterall?). Maybe it is the angle though.

I had the Jeep on stands and was letting it idle(damn thing goes 40 at idle with no load) and that's when I saw the problem with the SYE flange. Do you guys think the bind in the u-joint at the pinion could have caused vibrations that would have loosened the splines on the flange and caused what I originally thought was the problem? Also, wouldn't I have felt the vibes that were bad enough to cause that kind of damage? Just trying to figure this out. Thanks guys

Ary

P.S. Is there any reason aside from clearance to not put on a T-case drop with an SYE?

 

[bradlyw]

no reason u cant put a t-case drop in with an SYE...but the mechanic doesnt know what he's talkin about...one of the main points of an sye is to make it to where u dont need a t-case drop...so really there is no point in putting one on...that wont fix ur problem man.

Brad

 

[Safari Ary]

no reason u cant put a t-case drop in with an SYE...but the mechanic doesnt know what he's talkin about...one of the main points of an sye is to make it to where u dont need a t-case drop...so really there is no point in putting one on...that wont fix ur problem man.

Brad

Well, he's partially right, *I think*. He knows the formula to solve a problem, but he doesn't know the theory behind the formula. Chrysler says "if you have vibes, put in a T-case drop" So that's what he tells me. A t-case drop I believe would solve my problem, but I'd like to avoid it. I think I'm also in denial because I can't believe this problem would be as simple to fix as adding some 2* shims after I spent all that time replacing the output shaft and rebuilding the rear driveshaft. Oh well

Ary

 

[ChiXJeff]

Ary, that SYE flange should spin rock steady and concentric. Have you tried pulling the rear D/S and running it in 2wd to see if the shaft spins straight, or does it wobble?

Personally (and this is only a gut feeling) I'd bet on a runout problem on the shaft. Yes, I know, new shaft and flange. How about bearings?

 

[Safari Ary]

Last time I checked the shaft was spinning straight. It doesn't make any noises whatsoever when coasting which is what bugs me, if it were bad angles, they would be the worst during coast(maybe no load means less binding??). Also, if it were a loose bearing on the output shaft, wouldn't it wobble while coasting too?? I'm at a loss, and the dealer is being useless. Thanks guys

Ary

 

[Flowers]

First off, and I'm trying to be a dick, it's just reality, if you can't deal with a few vibes and the idiosyncrasies off a modified Jeep, then maybe you should consider a Passat.

Last time I checked the shaft was spinning straight. It doesn't make any noises whatsoever when coasting which is what bugs me, if it were bad angles, they would be the worst during coast(maybe no load means less binding??).

No, your pinion could be too high. Have you measured your angles yet?

Also, if it were a loose bearing on the output shaft, wouldn't it wobble while coasting too??

Not neccesarily. But if it did, you may not feel it without it being under load.

I'm at a loss, and the dealer is being useless.

Most are!

If you have a vibe that is only noticable under Accelerration OR (emphasis on OR) Deceleration it's angles. If it's noticable on acceleration AND (emphasis on AND) deceleration it's a loose sumpin' or other.

Flowers

 

[urbanXJ]

IMHO, dont pay the dealer to replace the anything.

It's an 01 correct?
Are you under the 36K mile mark?
If so, what does dealer say about the mods and warantee coverage?

I had copter sound anytime I was not accelearating.
2* shim made no diffrence.
AA kit and woods shaft made it all better.

 

[Kejtar]

Flowers.... I think you're missing a point.... It's not an issue of a bit of extra noise, but the issue that comes down to the fact everything was good after installs, he was running it for a while.... and suddendly extra noise started which is never good..... there was no mods done between no noise and start of noise (as I understand) so that means that something wore out or is wearing out....

Kejtar

 

[Safari Ary]

Flowers, I respect your input, but if you ever rode in my Jeep, you'd understand that this is not simply an idiosyncracy. People ride in my Jeep all the time and they're like "what's that squeak, what's that clunk, etc etc" I can deal with those things, but this thing literally sounds BAD, and it came out of no where.

Yes the Jeep is an '01, no it's not under warranty(56k miles, I drive a lot). Went to DC, then to Winchester, then back home in a day and a half, that's 700 miles, on a whim.

Anyway, the dealer called, they say there's definately something going on in the rear diff judging by the fluid. They want 200$ just to crack the diff and inspect, I told them to piss off and I'd be there to pick it up shortly. I'm gonna take it to Tim Shaker of www.shakerbuilt.com and have him install my gears and ARB and hopefully take care of the problem in the process since the entire diff's guts will be new at that point. Thanks for the help guys, I'm off to the outer banks for a couple days, I'll report back when I know something. Later

Ary

 

[Carpenter]

The way you describe the noise and how it comes and goes it sounds like an angularity issue. However, since you say it happened all of a sudden that doesn't make sense. You still really need to pull the rear shaft to help further diagnose the problem. Heck, it wouldn't hurt to do the same with the front just to know you're not chasing your tail. You also should measure the rear pinion and driveshaft angles. All the information you can provide will really help us and maybe we can help you.

 

[Carpenter]

I'm gonna take it to Tim Shaker of www.shakerbuilt.com and have him install my gears and ARB and hopefully take care of the problem in the process since the entire diff's guts will be new at that point. Thanks for the help guys, I'm off to the outer banks for a couple days, I'll report back when I know something. Later

Ary

Make sure he replaces the wheel bearing too. They don't cost much and it only makes sense to do it while the rear end it torn down. Also, have him check your rear driveshaft angle for you for giggles.

 

[STRYKER]

Make sure he replaces the wheel bearing too. They don't cost much and it only makes sense to do it while the rear end it torn down. Also, have him check your rear driveshaft angle for you for giggles.

Doesn't look this bad in the pics...
But do me a favor....

Measure the angle of the driveshaft itself with an angle finder. Tell me if you're close or exceeding 15*.
Just a hunch...

 

[goldxj]

I believe you were on the right track when you suspected the CV. I'm running a very different set-up then you, but, you're describing the exact scenario I dealt with for a few weeks. I'm lucky to have a DS shop in town (I should say a damn good DS shop). I pulled the rear shaft out, basically out of desparation, and low and behold, the CV was shot. When I checked the shaft, when it was on the truck, everything was tight, the rearend had just been rebuilt wheel cylinder to wheel cylinder(gears/bearings/carrier/seals/brakes/etc.) so I had a pretty good size list of suspect parts. After going over everything twice, it came back to the DS. I put the shaft in(after the CV was replaced, not rebuilt) about 3 weeks ago, and so far no noise. Good Luck.

goldxj

 

[XJCherokee99]

sorry to hear about the vibes, but i hear ya on the shim deal. I finally ended up ordering some from RE because not one auto parts store carried ANY around my town. pretty rediculous if you ask me.......

 

[Safari Ary]

Ok, back from Tuna fishing. What a great time.

Just to clear things up, I have run the truck with both front and DS's removed individually. The noise would occur with both in, and with the rear one in. However it would go away with the front one in and the rear one out. Looking at the pinion to DS angle I really don't think that's the problem because I've been behind my Jeep when it was floored and I definately have an axle wrap problem. Therefore, assuming it's the angle, it would theoretically go away during varied acceleration. However, it does it under the faintest acceleration, i.e. just letting the Jeep idle off the line, and it does it all the way up to full acceleration. Now a blown CV could be another problem altogether, but since there was a good bit of metal in the rear diff, I'm betting that's my problem. If not, well, I got my ARB and gears installed which I'd been trying to get to do for a year now(literally). So it's not a loss. I'll keep ya guys posted, thanks

Ary

 

[cbremer]

hopefully your gears solve it! i had a rapid ticking sound upon deceleration that varied with vehicle speed (not necessarily braking, just taking my foot off the gas) a while back and it turns out that i had a chipped pinion tooth. of course, at the time, my new gears were only in for 2 weeks and had to be replaced

 

[Flowers]

BTT

Ary,

Any updates on the vibration?

Flowers