Roaring sound from rear axle?

[ShakeyJonez]

Hey guys. I'm new to the boards here. I just picked up a 88 Comanche 2WD/Automatic for $900. The body has zero rust and only 147,000 miles on the 4.0. However there is a somewhat loud roaring sound coming from the rear axle. I also have a 96 Cherokee and it doesn't make this sound at all. Is there anyway to test/figure out what is causing the problem without taking the axle/chunk apart? A local mechanic said just to replace the axle but I priced one via the junkyard network and they wanted $700 shipped. Surely there is a cheaper solution for a good ol GA boy like me.

 

Numbers on the axle are

 

42106

268 6

REV D

11-13-85

[foreman1063]

$700 for a Dana 35 is crazy. If you look around in local junk yards you could find a Cherokee Dana 35 for around $100. Weld on new spring perches and your in business. Just make sure you find a donor axle that has the same gear ratio as your truck.

Another option of course, is to fix the axle you have. It may be as simple as a bad wheel bearing. About $20 and two hours work. Or the problem may be R & P or bearing noise.

Can you describe the noise in more detail? Is it heard under acceleration, while coasting or constantly. Narrowing this down can help diagnose if the problem is gear noise, pinion bearing or carrier bearing noise or wheel bearing noise.

[Cheech]

First thing I would do is make sure you have oil in that diff. Then go from there. If its been running dry, it could be beyond fixing.

[mkbruin]

D35's are throwaways, and you should never spend more than $100 for one. Ever.

 

If yours is bad, a ford 8.8 or dana 44 swap may be in order... or grab another 35 out of a Cherokee and burn in new perches... although you should also be able to locate a few MJ's in the pull-n-save for a direct bolt-in swap also.

[ShakeyJonez]

Well I took it down the road to get a better listen and it makes the roaring sound even when I let off the gas or accelerate so I'm pretty sure it's a wheel bearing. That's my guess anyway. Also it feels like maybe the back breaks aren't working so I'd think maybe the axle seals might be leaking cause them to malfunction possibly.

 

Anybody got any advice on taking this thing apart? I've searched the site and found a few threads but any help is grateful.

[mvusse]

D35's are throwaways, and you should never spend more than $100 for one. Ever.

 

If yours is bad, a ford 8.8 or dana 44 swap may be in order... or grab another 35 out of a Cherokee and burn in new perches... although you should also be able to locate a few MJ's in the pull-n-save for a direct bolt-in swap also.

 

Before grabbing a 35 out of a Cherokee I'd grab an 8.25" out of a 97 or newer one (29 spline). Not quite a D44,but MUCH better than a 35.

 

As Pete told me before (and I agree): NEVER spend money on a 35 besides gear oil and brake parts. They are junk.

[ShakeyJonez]

Does anyone know the correct gear lubricant to use for a Comanche? I'd like to use synthetic if possible for the longevity and performance. I was looking at this one. I dunno if this is the correct weight though.

 

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_Synthetic-Gear-Lubricant-LS-75W-140-%281-qt-%29-Mobil1_7070076-P_N3242_T|GRP2035____#fragment-1

[jimmy21669]

I would use off the shelf GL5 75-90. Advance Brand...non synthetic.

 

It IS a dana 35 after all. I have used generic 75-90 in axles with ZERO issues for years and you will have beer money left over.

[ShakeyJonez]

Thanks for the help guys. Turns out the rear drivers side axle shaft is warped and needs to be replaced along with the bearing. I also found out I need to replace the rear transmission line, drag link and track bar. Hopefully the cooler for the tranny isn't stopped up. I'd hate to have to buy a new radiator too. I can't wait to get all this stuff finished so I can enjoy this new truck instead.