Over torqued pinion nut

[abillerbeck]

So I have 2002 Ranger XLT Supercab 4x4 with the 8.8" 4.10 non L/S rear axle (code 97) with 212,000 miles on it. The pinion seal was leaking and I replaced it in a hurry right before a 500 mile road trip. In my haste to replace it I was running the pinion nut back on with the rattle gun with the intent to stop and use a ratchet before I ran it all the way on.... well I didn't stop fast enough. I back the nut off a bit and finished buttoning it up anyways, took it for a test drive and seem to do fine. By the end of the trip it was obvious that something was tight in the rear end... harder to accelerate.

The question is... how much damage have I done? I've asked a few shops around me about rebuilds and they all want $1,000+. I really don't want to spend that kind of money on the truck because of it's age, I'm also not sure how much longer the trans is gonna hang in there. I'm thinking a junkyard or ebay axle may be a better deal. Found some for $400 with relatively low mileage (less than 120k). Will a R7 axle code with the L/S be a direct swap into my truck?

Any other options/suggestions I should consider?

 

[franklin2]

Why did you back it off? I have always zipped them on with the impact and never had a problem. If you think you are going to crush that sleeve more, think again. It's very difficult to crush. Have you ever tried to crush a new sleeve? It takes a lot of torque to crush them.

I would not panic. I would jack it up, and with the transfer case in neutral, I would mess with the driveshaft and see if you can tell what's going on.

 

[abillerbeck]

I backed the nut off a tad because it was so tight that I couldn't turn the flange at all. I've never crushed a new sleeve before so I don't have a feel for what it takes, but my impact gun is rated for 700 ft lbs.

 

[Roert42]

So, once the crush sleeve is over torqued, then you can't re set it, it's already been damaged. You can reuse a used crush sleeve, but the preload is going to be different. I don't remember the numbers off the top of my head, but something like 9-14in/ilbs old vs 24-27 in/ilbs new.

That said, if the bearing preload is wrong you can wreck the bearings in a hurry.

All that said, it's not hard to rebuild the axle if you are not changing the gears or carrier since all the shims should just stay the same. You would need a torque wrench (in/ilb) to et the preload, and a press to get the pinion bearing off, if you had a slide hammer you could replace the axle bearings while you had it apart.

Probably faster to just swap axles if it is your DD, but a freshly rebuild axle would be worth the extra effort if I had the space/tools.

 

[Uncle Gump]

I think you probably have other things going on here...

The pinion nut gets torqued north of 200 lb-ft. Your "rattle gun" would have to have pretty big balls to go north of the spec and crush the sleeve further.

 

[franklin2]

I backed the nut off a tad because it was so tight that I couldn't turn the flange at all. I've never crushed a new sleeve before so I don't have a feel for what it takes, but my impact gun is rated for 700 ft lbs.

If you could not turn it, then yes you must have over done it. I would still get back there and investigate, and if it looks ok, tighten it like the other poster said till you have some resistance but can still turn it. There is some pressure on those bearings at all times, which is called the "pre-load".

 

[19Walt93]

Once the crush sleeve has been crushed the original time a good 1/2" impact will definitely be able to crush it further. If' it's been over torqued, it needs a new crush sleeve, if it's been run with loose pinion bearing preload it probably need pinion bearings.too. If you get to that point change the carrier bearings,too because they've been running in the same oil.

 

[abillerbeck]

Once the crush sleeve has been crushed the original time a good 1/2" impact will definitely be able to crush it further. If' it's been over torqued, it needs a new crush sleeve, if it's been run with loose pinion bearing preload it probably need pinion bearings.too. If you get to that point change the carrier bearings,too because they've been running in the same oil.

How would you rate the difficulty of a job like that and do I need any special tools to do it? Looks like I can get a rebuild kit on RockAuto for about $100 as long as I don't have to replace the ring and pinion as well. I'm trying to weigh the cost/benefit of rebuilding vs throwing another axle under it. One pro of the complete axle replacement is I could trade my 97 for an R7 and have a limited slip instead of just an open diff.

 

[adsm08]

Straight bearing replacement isn't that hard. A press is needed for getting them on and off though.

Shims and what not may also be needed to reset pinion depth, backlash, and preload.

 

[franklin2]

Just because it locked up the bearings doesn't necessarily mean the crush sleeve was crushed too much. I would get back there and check it. I would loosen it up some and see if it turns smooth. If it does, I would tighten the nut back up. If it has a lot of torque on it, and the pinion still turns, it should work. If the nut doesn't have much resistance or torque before the pinion locks up, then yes I would get another sleeve. If the pinion is not smooth, then the bearings may be ruined also. Nothing beats going back there and messing with it a little bit.

 

[abillerbeck]

Thanks for all of the input. Looks like the seal is still leaking and with the driveshaft disconnected the flange was impossible to turn by hand without loosening the pinion nut. I loosened the nut and could turn it, but it feels pretty crunchy... bearings are definitely smoked. I think I'm gonna buy that $400 axle off of ebay and throw that under there (bonus on the limited slip).

 

[19Walt93]

Just a suggestion, if you get your used rear end from a local salvage yard it should be less of a head ache if you have to exchange it due to problems. A yard that you've done business with before would be my first preference.

 

[Uncle Gump]

Man... you must have hammered the snot out of that pinion nut with your impact to further crush the sleeve.

You learned an important lesson on this one.

My guess is that there were issues before you replaced the pinion seal. Like maybe it was run empty or really low... and burned up the pinion bearings.