[techlh]

Hello

I need to replace the rear end in my 98 Durango. Can someone please tell me how to identify it, so I purchase the correct replacement? Apparently there are different numbers, and an incorrect install will tear up the transfer case. I'd prefer not to do that? :lol:

 

[Neil]

What exactly are you replacing? Axles, gears? There were two gear ratios. 3.55 was standard. 3.92. Two axle sizes. 8.25 and 9.25 The 8 has an oval 10 bolt cover. The 9 is an octagon 12 bolt cover. LSD differental was optional. What do mean tear up the transfercase? You should be able to use any of the above combinations.

 

[techlh]

Well, here's what was happening: http://durangoclub.com/forum/viewtopic.php?t=2700&highlight=

Finally about 2 weeks ago it locked up tight. I can't move it from the garage, can't afford to get it towed, etc. I'm borrowing the money to get a new (used or rebuilt) rear end, which I can install myself.

My wife tells me that maybe there's something easy to replace, but I think we just need a new entire thing. I'm sure I couldn't take this one apart and replace all those little gears? this rear end was rebuilt in 2002 by the dealer for a similar problem.

 

[tomk]

Yes, if you end up with mismatched gear ratios in the front and rear, you can trash the transfer case.

There should be a metal tag on the differential identifying the ratio (but it's not uncommon for mechanics to 'forget' to replace the tag when changing the axle fluid.) The paper tag on the left axle housing might also still be visible.

?tom

 

[Volphin]

Yes, the ratios must stay the same. 3.55 ratio up front means you need 3.55 ratio in the rear. The same goes if you have 3.92 ratios, you always match them. What you don't have to match is the axle case or housing. The 9.25 rear end (12 bolt cover) is a more robust unit than the 8.25 (10 bolt cover and tapered ends at the wheels.) Additionally, if digging about a boneyard, find one with a limited slip feature. There's no real cost difference and it provides better traction than an "open" diff. Check locally for a boneyard that'll give you a 30 day warranty on a good low miles unit and pull the cover and inspect the wear pattern on the ring gear (the large one) before buying.

HTH

Bill

 

[techlh]

Great advice, Volphin.

Any idea what I should expect to pay for a used low-mileage or rebuilt rear end?

(That doesn't sound very good, does it?)

 

[Volphin]

Half a house for a 5 year lease or $50 per day. :lol:

All kidding aside, I'm thinking $350??

Bill

 

[Big Al]

After reading your other post and the problem you found with the rear brakes, I have to ask if you've actually removed the rear diff cover and taken a look at the innards :?

If not, I'd suggest you do so before slapping in a replacement axle to verify you "really" need a new diff and it's not something else. (it'd bite to shell out the cash and put up with all the hassle of replacing the diff only to find you still have the same problem when you're done! :wall

With both rear wheels off the ground and the cover removed, it "should" be obvious what's wrong if you manually rotate a wheel while watching the gears inside the diff. It's even possible you might find the problem is something easily fixed without replacing the whole diff? i.e. the pin holding the side gears in place fell out, one of the side gears broke apart, the splines on the end of a drive axle stripped out, etc.

<b class=alert>Updated[/b]

BTW, if the tags IDing your gears are missing, you can request a build sheet from Dodge by filling out the form at Contact Dodge with your VIN# and they'll e-mail it to you usually within 48 hrs. The gear ratio is normally toward the bottom of the first page in the section where codes D??? are listed.

 

[Neil]

Woops, forgot to ask if he was 4x4 or 4x2

 

[Smash]

Guys I don't know about any 'tag' on the differential - my '99 has, on the drivers side rear of the axle, a white sticker "3.55 trac-lock" which has ratio and type (obviously) on it. - This sticker is in-between the two U-bolts.

A local guy here in PC was gonna charge me around $300 labor to change the ratio, plus $150 parts.

Smash

 

[MWeed]

I'd be very afraid of someone who tells you what it's going to cost, parts and labor, without looking to see what's actually wrong with your vehicle. No reputable shop or mechanic can do this. Money may be tight, but don't waste it by paying someone to have something done when neither of you know what's wrong. You'd be money ahead to have a qualified shop do this repair for you.

It sounds like he thinks that bearings will be all that's needed. What's he going to do when he opens it up and finds you need gears or axles or a new trac-loc unit? People like that usually won't guarantee their work and if something else goes wrong, you end up paying for the same job to be done twice.

A bandage repair will cost much more in the long run. Get it done right.

 

[techlh]

My truck is 4x4. This advice is priceless. I'm going to take the cover off tonight and jack this baby up, see if I can see what's binding. Thanks!

 

[greg]

BTW and just for what it's worth, I ordered my D with the 3.9 gearing. Six months later I got a notice from DC that tells me they inadvertently installed the 3.55 gears and I could either opt for a refund or have it changed out by the dealer. I took the refund but never checked what the tag says. I'll have a look as to whether the mismatch ended with the gears only or if they also put the wrong tag on it.

greg

 

[tomk]

The axle mixup happened on early 99's, and the tag is correct? My '99 came that way? I did the same as greg and took the money rather than the gears?