Noisy rear end

[WesChapman]

2005 Renegade 92k miles never used off road. 3.7, auto. Completely OEM right down the the original shocks & springs. (yes, the ride *****)
Around 42k miles I starting hearing a faint howling noise from the rear end @ 60 MPH while under load. The noise goes away when coasting. Changed the diff oil at 60K miles. The wear pattern on the ring gear looked normal and the spiders gears looked OK. There was a small build up of a gray slippery gunk on the bottom of the housing, but it was not magnetic, nor abrasive feeling. Kinda felt like the stuff that comes out of my 3 year son's nose during cold season. Now at 92k miles, the howling is much louder. I changed the u-joints and while that corrected a clunking noise I would hear when the ****** shifted, the howling noise didn't change. I start hearing it about 45 mph; it's loudest at 60 mph and then hardly audible at 75 mph. The noise completely goes away when coasting. About two weeks ago I started noticing a slight vibration in the drive train that goes away after a few miles of driving each morning. Called a rear end shop, described the noise and he thinks the rear end will need a complete re-build to the tune of $800 to $900. He also claims he see's a lot of vehicles between 90k to 150k miles needing rear end work. That claim seemed suspicious to me, but in my 20+ years of driving, I've only kept two vehicles for more than 50k miles, so maybe? One was a 1980 Scout II diesel (141k) and the other has been this Liberty.
Is there anything else I could check on my own, before going to a shop?

 

[tjkj2002]

Do you have the trac-loc? If so try changing the fluid again and actually adding the friction modifier.The non-magnetic stuff your referring to could be the clutch material and it may be to late for that LSD.Your also a bit late on your diff services,should have been done every 12k-15k.


On the other hand it could be the pinion bearings going and then yes it will cost a pretty penny to have rebuilt.The use of synthetic gear oils have reduced the longevity of diff bearings over the years.Should use dino gear oil only,will see a mpg hit but your diff bearings will be very happy.

 

[SMETNA]

Does this sound similar?

http://www.jeepkj.com/forum/showthread.php?t=45076

You may need the rear diff checked. Mine is having the same issue at 30k miles, and the bearings are getting replaced. Yours Shouldn't be $900 though.

 

[Atrus]

Wife complains about my noisy rear end all the time.

Luckily, the KJ is quiet!

 

[family KJ]

x2 on the friction modifier if you do have the trac loc... It solved...at least my KJ's...rear end noises

Check out the bottom left side of your rear axle, there should be a bluish tag wrapped around the end, that will give you the answer for the above question.

 

[WesChapman]

Do you have the trac-loc? If so try changing the fluid again and actually adding the friction modifier.The non-magnetic stuff your referring to could be the clutch material and it may be to late for that LSD.Your also a bit late on your diff services,should have been done every 12k-15k.




On the other hand it could be the pinion bearings going and then yes it will cost a pretty penny to have rebuilt.The use of synthetic gear oils have reduced the longevity of diff bearings over the years.Should use dino gear oil only,will see a mpg hit but your diff bearings will be very happy.

Open diff, no LSD. Used dino oil at fluid change. 12-15k? Damn, guess I screwed up on that one. Could have swore I read 60k service interval in the manual. With my driving habits, that's gonna be 2-3 changes per year. I consistently get 18.9 mpg which I'm quite happy with.
I'll take her to the rear end shop this Friday and go from there. I've been wanting a LSD anyway.....

 

[WesChapman]

Does this sound similar?

http://www.jeepkj.com/forum/showthread.php?t=45076

You may need the rear diff checked. Mine is having the same issue at 30k miles, and the bearings are getting replaced. Yours Shouldn't be $900 though.

The howling noise the OP talks about is dead on with mine. Don't have the growling noise though and my ****** shifts fine. I think I have an expensive repair ahead of me. I don't have the skills or tools to tackle this one. I'll talk to the shop Friday and see if I can save myself a couple bucks by removing the axle and bringing it to them. I wish I had more $$$ cuz I'd really like 4.10's and a LSD.

 

[avalanchejf9]

Lay off the beans buddy!

 

[WesChapman]

Lay off the beans buddy!

Beans, beans, the musical fruit, the more you eat, the more you toot...

 

[WesChapman]

bummer

Took the Jeep the the rear end shop today. Rear end is worn out and needs a rebuild. <sigh>

Now I have to decide which child to sell to pay for it. They are both being really sweet today, but it won't last.

 

[LibertyFever]

Took the Jeep the the rear end shop today. Rear end is worn out and needs a rebuild. <sigh>

Now I have to decide which child to sell to pay for it. They are both being really sweet today, but it won't last.

Did they tell you exactly what's "worn out"? Likely the pinion bearing.

Is there any chance you can find a Libby with low mileage in a local wrecking yard? Rebuilding a diff does take some skills but swapping one takes even less. Maybe you'll get lucky & find a LSD

 

[Jeepman56]

You could sell me your light bar (if your Rene has one) to ease the financial pain.

 

[belvedere]

12-15k? Damn, guess I screwed up on that one. Could have swore I read 60k service interval in the manual.

The severe service schedule DOES say 15k, BUT with this footnote:

‡Off-highway operation, trailer towing, taxi, limousine,
bus, snow plowing, or other types of commercial service
or prolonged operation with heavy loading, especially in
hot weather, require front and rear axle service indicated
with a ‡ in Schedule “B”. Perform these services if the
vehicle is usually operated under these conditions.

The 15k figure is frequently thrown around on this board, but without mention of the conditions that require it. IOW, the manual doesn't require it for all conditions, or even for all SEVERE conditions. Certainly some on here "usually operate their KJ under these conditions", but most do not.

 

[tjkj2002]

The severe service schedule DOES say 15k, BUT with this footnote:

‡Off-highway operation, trailer towing, taxi, limousine,
bus, snow plowing, or other types of commercial service
or prolonged operation with heavy loading, especially in
hot weather, require front and rear axle service indicated
with a ‡ in Schedule “B”. Perform these services if the
vehicle is usually operated under these conditions.

The 15k figure is frequently thrown around on this board, but without mention of the conditions that require it. IOW, the manual doesn't require it for all conditions, or even for all SEVERE conditions. Certainly some on here "usually operate their KJ under these conditions", but most do not.

99.99% of all owners fall into schedule B,there is more for requirements for B that you are not listing.

 

[ptsb5a]

I don't always operate my KJ under those conditions but.... I've been changing my diffs and t-case out at every 20K kms and at 132000 kms I've yet to have a problem. With frequent changes I doubt that I'll ever have a problem.

That said I better go and knock wood somewhere.

 

[belvedere]

99.99% of all owners fall into schedule B,there is more for requirements for B that you are not listing.

Right, most folks do fall under Schedule B. However, that 15k interval for changing diff oil has the footnote that I quoted, and that IS in Schedule B. IOW, even under the Severe Schedule B, the 15k interval is only required if the KJ is "usually operated under these conditions". I know that your KJ probably is, but mine isn't, and I would guess that many others aren't, either.

Your manual may read differently than mine, since they're different model years. The footnote I quoted was copied and pasted from page 378 of the 06 Owner's Manual.

 

[belvedere]

Of course, changing it more frequently than required is just fine. I'm just saying that the manual doesn't require it that often for the way most owners use their vehicles.

 

[tjkj2002]

Right, most folks do fall under Schedule B. However, that 15k interval for changing diff oil has the footnote that I quoted, and that IS in Schedule B. IOW, even under the Severe Schedule B, the 15k interval is only required if the KJ is "usually operated under these conditions". I know that your KJ probably is, but mine isn't, and I would guess that many others aren't, either.

Your manual may read differently than mine, since they're different model years. The footnote I quoted was copied and pasted from page 378 of the 06 Owner's Manual.

Schedule "B" is to be followed if..................

-Day or night temps are below 32 degrees
-Stop and go driving(over 95% of all drivers)
-Extensive engine idling
-Driving in dusty conditions
-Short trips of less then 10 miles(over 90% of all drivers)
-More the 50% of your driving is sustained high speed driving in temps over 90 degrees
-Trailer towing
-Taxi,Police,or delivery service(commercial service)
-Off road or desert driving


I doubt there is 1 person that does not fall into one of those items.I know you fall into the schedule "B" since you live in SD.

 

[belvedere]

I doubt there is 1 person that does not fall into one of those items.I know you fall into the schedule "B" since you live in SD.

I agree 100%. I'm saying that on Schedule B, it lists a 15k interval, and has a little "‡" symbol beside it. Then, at the end of Schedule B, there are footnotes. The footnote beside that symbol says:

‡Off-highway operation, trailer towing, taxi, limousine,
bus, snow plowing, or other types of commercial service
or prolonged operation with heavy loading, especially in
hot weather, require front and rear axle service indicated
with a ‡ in Schedule “B”. Perform these services if the
vehicle is usually operated under these conditions.

Like I said, this is from the 06 manual. Maybe other MY manuals read differently.

 

[WesChapman]

A vs B

So basically, if you turn the key and start the engine, use schedule B. If your KJ sits in the drive way, never moves, use schedule A?

I do plan to look around the wrecking yards, but I only know of two. One is about 80 miles away, the other about 50. There used to be a Jeep wrecking yard in Sacramento, but I can't remember the name. Time to Google.

Sorry Jeepman56, my Rennie didn't come with the light bar.