Need help w/front diff noise

bryson

RME Resident Ninja
Supporting Member
Location
West Jordan
The frequency of the sound makes me think t-case... I would expect an axle issue to sound more "detached." That noise sounds like it's right inside the cab.

I really don't think it's your locker, because when you are moving in a straight line, the entire locker spins, but nothing inside it moves - not even the spider gears, but the noise is obvious when you are driving straight. Bearings maybe, but NOT the locker.

Have you pulled the fill plug for the t-case to see if the fluid has metal flakes in it?
 
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DAA

Well-Known Member
Supporting Member
Have you pulled the fill plug for the t-case to see if the fluid has metal flakes in it?

I have not. But that sounds like a logical next step. Not sure if I'll be able to get any time to mess with it today or not, but if I do, I'll have a look at the t-case fluid.

- DAA
 

DAA

Well-Known Member
Supporting Member
Well... Crap...

If there is anything going on in the t-case, it isn't showing up in the fluid. It all came out clean and clear and smelling fine. No sparkles in it at all.

This is wearing me out. I'm ready to punt and take it to someone more qualified to troubleshoot it than I appear to be. Not sure if Carl wants to take on something like this, if not then next on my list is probably Teraflex, unless someone has a really good shop here in Davis county to recommend.

- DAA
 

Jinx

when in doubt, upgrade!
Location
So Jordan, Utah
I would pm Carl or call him if you have his number. He has been around long enough to probably have seen what you have broke. :).

(not saying you are old Carl)
 

thenag

Registered User
Location
Kearns
PS...if you are going to be removing the diff covers multiple times during this project, which it sounds like you may, why not invest in some lube locker reuseable gaskets? I have never used them myself, but I have heard good things about them.

I have had good luck using a paper gasket coated with axle grease. (I have not tried this with synthetic gear oil)

nathan
99 xj with stuff
 

bryson

RME Resident Ninja
Supporting Member
Location
West Jordan
Pull the front driveshaft and see if it changes

Welcome to the thread, Stratton. You might want to read it first, though.:p

Jinx said:
I would pm Carl or call him if you have his number. He has been around long enough to probably have seen what you have broke. .

(not saying you are old Carl)

He is old... no point in hiding it.:)
 

Bob B

Registered User
SO... maybe way off, but by the sounds on the video, it sounds like really badly cupped tires. That would give you the Waa-Waa-Waa. You said the wheel bearings were really toast, that would cause really bad cupping..Try rotating the tires front to back.. Just a thought..
 

DAA

Well-Known Member
Supporting Member
Bob, that is the plan for today. The tires don't "look" bad, but, as toasted as the unit bearings were, I do not doubt that they have some feathering or cupping. Figure since I bought the tires from Discount, I may as well let them rotate and balance them for me - so I'll be taking it over there in a couple hours. It really doesn't sound like tires to me, but, I'd sure love to be wrong about that...

- DAA
 

rholbrook

Well-Known Member
Location
Kaysville, Ut
While the front driveline was off, did you lift the front and spin the tires and hear the noise? If the noise is in the t-case you won't hear it then. If your rotating it with the driveline in the noise can travel so it sounds as if it's in the axle.
 

DAA

Well-Known Member
Supporting Member
Well, no change after rotating the tires. Was worth a shot.

Russ, I'm not 100% sure the sound I can hear/feel when spinning the front tires is even related to my driving noise. I'm almost starting to think that it's just normal. But, to answer your question, no I don't think I tried lifting the front end and spinning the tires with the drive shaft disconnected. The noise was still there driving it with the front shaft off for sure though.

Couple observations from this morning...

After letting it sit for a day or two, the noise is barely there until after being driven for a bit. Something about sitting, whether it be getting cold or oil settling somewhere or whatever, makes the noise quiet itself a lot. Thinking about it, I've seen this a few times now since it started - where it seemed gone for a little while after sitting a long time.

I think it definitely is worse, or louder when coasting. On the way back from the tire shop I was playing around and I could make the noise come on strong by letting off the gas all the sudden, then make it get quieter (but not go away) by applying just a little bit of throttle.

Just do not know. You guys talking t-case are making sense to me. But with the fluid looking so good, I'm really hesitant to just pull the case and crack it open. And I'm just plain running out of time. I'm leaving this afternoon for Boulder Mountain (not in the Jeep and a different kind of trip now...). And have a backpacking trip in the Uintas next weekend. I called Teraflex and they can't get to it until next Thur., but as of now, unless I can pin it down the first part of next week, I think it's going to them...

- DAA
 

rholbrook

Well-Known Member
Location
Kaysville, Ut
The noise is not normal. Pull the front driveline and put the front on jack stands and spin the tires. If there is noise, it's in the front end, no noise, transfer case I had a squeak from my front end and it was a U joint in the front passenger side. By pulling the drive shaft and driving it you have not eliminated anything because it is all still spinning together.
 

DAA

Well-Known Member
Supporting Member
Nope. Haven't had any time to even look at it since last week. And won't have any time for it within the next couple of weeks. So I dropped it off at Teraflex this morning. Haven't heard anything yet.

I'm leaning more towards t-case. But, obviously I don't really know. Hopefully Teraflex figures it out by tomorrow morning, otherwise I'll be out of pocket and off the grid again until next week.

- DAA
 

DAA

Well-Known Member
Supporting Member
So, just got the Jeep back from Teraflex, noise gone.

Turned out to be a ring & pinion/carrier bearings - in the REAR, not the front... When I got Ben out for a test drive as soon as he heard it he was thinking something in the rear diff and turns out he was right. Even after he told me he thought rear, I still couldn't tell just by the sound where it was coming from. Maybe it has something to do with how truly terrible my hearing is. But I think finding those bad (reallly bad!) unit bearings when I first started troubleshooting this might have got me fixated on the front. The few other people that heard it all thought it sounded either right underneath them (t-case) or in the front too. But, like I said, Ben immediately thought rear and he was right.

But it looks like bad setup on the inital install at Six States was probably the root of it all. No pre-load on the carrier bearings, the guys at TFP said the carrier just fell out, pattern on the teeth looked all jacked, carrier bearings felt choppy. Thinking with no preload on the bearings, the carrier was able to shift under load and after 30,000 miles it finally started wearing bad enough to start making my noise.

I want to thank everyone that offered help here though - I really do appreciate it!

Now I need to get these new gears broke in before I head down the the Henry's in a couple weeks.

- DAA
 
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