So an hour into my weekly drive from Charlotte to Raleigh I notice I've got a trailing oil cloud. I let off the gas, hear a lot of whirring when I do, then pull over and coast to the upcoming exit. Just as I come up and off the side of the exit ramp, it sounds like a fucking box of wrenches has just fallen off a truck so I park it and check out whats up.

The underside of the entire bed is coated in diff gear oil coming from the pinion area, which was hitting the exhaust piping and causing the oil cloud. The driveshaft was hanging only by the front end in the transmission and was causing all the noise by flailing the other end between the road and my gas tank. After noticing the splines and threading on the differential pinion was intact I looked back down the interstate and saw my pinion nut and washer laying in the middle of the road. So while waiting for the AAA tow truck to arrive I got to wondering if the nut just came off by itself (unlikely) so while trying to realign the pinion yoke splines I found the pinion was wobbling a lot. Not like a couple thousandths of play I mean about half an inch. I just reattach the shaft and waited it out (kind of stupid looking back on it but I was in a rush and wasn't thinking).

The truck is 96 ram 1500 2wd with a longbed, 210k miles. I'm pretty sure the diff is a chrysler 9.25 but I can't be certain as it's sitting back at my father's place. I noticed the driveshaft and pinion I had to take a piss so I went inside when the flatbed dropped off the truck in the middle of the driveway. Guy didn't even check my AAA card or have me sign anything. Unfortunately I had to move it so my father could get in so I tighten the pinion nut and crank her up to see if it can limp over and up 20ft into the yard. No problems. Checked out reverse, which gave a jerky ride for the few feet I backed up so I pulled back forward a bit and shut it down.

I've never messed with the internals on a diff before. My questions are:

What the fuck happened? I assume the pinion bearing(s) went out, after 210k miles. Maybe causing some hella vibration that got the pinion nut loose.

Everything else on the truck runs/works fine so I'd rather fix it than part it out. Am I looking at replacement of the pinion seals/bearing and pinion? Or is this something that basically could have fucked up the entire internals and would be best to get a used axle at a junkyard?

Going to pull the diff cover next weekend and see if I receive any gifts of sheared teeth for my trouble.


[Edited on June 29, 2009 at 1:14 AM. Reason : trying to paint a better picture]

6/29/2009 1:10:29 AM

if the nut comes off, it will be loose, thats what puts the preload on the pinion bearings

6/29/2009 7:54:22 AM

Hrmm, I didn't even think about that, so just like front spindles. But would the nut coming loose by itself have caused all this headache? It's never been worked on before or altered so I thought that woulda been a symptom, not the original problem.

6/29/2009 8:04:54 AM

if you end up having to replace the pinion, you'll need to replace the ring gear also. might be cheaper at that point to get a junkyard axle.

if you want to fix your existing axle, I have a guy in Durham who can take care of you. He's very good at what he does. http://www.eastcoastgearsupply.com is his website.

6/29/2009 10:24:49 AM

^Chase at ECGS does top quality work. Just had a Ford 8" shortened, regeared, etc. for my roommate's hillclimb car.

6/29/2009 10:32:45 AM

sounds like a full rebuild is in order. the housing should still be okay. RoscoTheRam did have an extra 9.25 sitting around, let me get up with him and see.

also, fwiw, once the pinion nut comes loose on those axles you can't really just retighten them thanks to the wonderful crush sleeve.

6/29/2009 11:05:14 AM

Can you get crush sleeve eliminators for those?

6/29/2009 4:13:35 PM

So while at work today I read up on my Haynes n00b manual and saw very little on tearing down a diff. I also looked around a bit online and only found one complete 9.25 listed for $350 used off a 98 durango in my area. ^^ Think your buddy is willing to part with his? If he is, PM with the specs and price. My options are still pretty open right now, between either a rebuild kit/parts and do it or just a whole axle swap if it's cheap enough.

[Edited on June 29, 2009 at 7:31 PM. Reason : ^ I saw a few sites selling a couple shims that said they replace the OE crush sleeve]

6/29/2009 7:30:26 PM

if its a 4wd you need to get the right ratio to match the front

[Edited on June 29, 2009 at 7:51 PM. Reason : fyi, you can pull the outer bearing and put in a new crush sleeve if its not torn up too bad]

6/29/2009 7:50:56 PM

^^^yes. i've heard of a lot of people having issues with them though. i've never used one personally. a properly crushed/torqued crush sleeve works fine, it's just the "hassle" of having to use a new one anytime you work on the yoke/bearings/pinion.

^^yeah, i know he wanted to sell it, i'm just not sure if he still has it. i left him a message about it today, i'll let you know what he says. you can't use a durango axle. shafts, brakes, and housing width are different. well, you could use the gears/carrier out of it... just not anything else.

^iirc it's a 2wd.

6/29/2009 9:43:39 PM

Yeah 2wd, prefer stock gearing of 3.9ish if at all possible. I'm seeing most places showing approx $100-150 for most of the bearings, seals, and misc parts. ^Thanks, keep me updated. So what garage gods are still up for making some side money? I'd attempt it but I have a lack of proper tools. Gonna call up the ECGS place tomorrow.

[Edited on June 29, 2009 at 10:40 PM. Reason : .]

6/29/2009 10:36:12 PM

yeah, call up ecgs and talk to chase. tell him ivan (me) or matt (jeepman) referred you. he's actually working on an axle for me right now too.

your stock gears are probably 3.55 or 3.92. 3.55 was the most common ratio. some 2wd's also had 3.21's, but not many. the only half tons to get 4.10's were the off road editions. there should be a sticker in your glove box with some build codes on it. one of them will say the gear ratio and if you've got a limited slip or not. it'll say "axle ratio 3.55 AS (anti spin)" or something to that effect.

if you end up rebuilding the current axle, i would definitely recommend stepping up to 4.10's. makes a nice difference in performance without hurting fuel mileage.

[Edited on June 29, 2009 at 11:22 PM. Reason : there might be a laminated sticker on the axle tube also if it hasn't worn off]

6/29/2009 11:15:11 PM

Had my old man check out the glovebox and look for around the axle, no dice. But he did confirm it was a 9.25" 12 bolt. Called up Chase, you guys are right, he's a nice guy. Told him the vehicle specs and asked about doing a rebuild, he basically guessed right with what had happened. Personally I never heard of it, but he said it's common for the pinion to back off over time and finally just come loose.

Not happy about the price, $600 out the door, but he said he could knock it out in a day, 2 days tops.

6/30/2009 7:06:22 PM

but keep in mind you'll have new gears, new bearings, and the best part is that you know it's done right and you don't have to worry about it anymore.

this coming from a guy who had two gear installs fail and then had chase do it the third time. take that 600, multiply it a few times, and then think about having chase do it once. sounds a little bit better lol

6/30/2009 7:33:53 PM

Yeah, I honestly didn't know if he was joking about a 5 year warranty. I'm just not used to giving up $600 for car repair, but I know with my luck it would fail with my half-ass job.

6/30/2009 9:05:16 PM

if you do it half ass twice then its a whole ass job

7/4/2009 9:21:15 PM