Rear End Banging

[jeffzielin]

Hi Gang,

I have a 2002 4X4 Limited Diesel Excursion. I'm pretty sure I need to replace the rear end in the truck. About 4 months ago it started making banging noise on acceleration and it got worse over time and now has settled in to a loud banging with throttle pressure. I can only guess it's bad.

I'm pretty mechanically inclined and would like to know if anyone here has attempted to replace a ring and pinion on these trucks igf this is what it is? Is it worth the cost savings of trying it myself or should I just pay to have it repaired?

Does anyone have any threads or links to a step by step guide to replacing the guts on these rear end?

Any help would be greatly appreciated. Thanks in advance!

[GSF35099]

Not to say the rear end isn't bad, but take a look at your drive line and see if the center bearing is bad. Might be a cheaper fix. Mine was slamming on take off and acceleration and it was that.

[RT]

Banging noises would scare me - rear ends usually making grinding or winding noises when they go. This rear end is a little harder to set up than some. It utilizes crush washers in the pinion to set bearing pre-load. It requires an inch pound torque wrench to measure rotational torque as you tighten it down. Even a lot of driveline shops don't do it right.

If you are having a banging noise, I'd be more inclined to look at your slip joint. It is a known cause for that noise in the driveline. Here's a link: Slip joint regreasing

[jeffzielin]

Yes I did check the driveline. It all checked out. The way I narrowed it to the rear end was I got the read wheels up off the ground and had the wife put it in drive and give it gas. With a metal rod I checked things and it was definitely the rear case.

[nycpsd]

One though before you tear into the rear end would be have you grease the slip joint on your drive shaft this tend to start banging when they aren't greased.

[Oneof6]

Jeffzirlin; Diagnosing by sound like you did on a drive line can fool someone into thinking that what they are hearing is right near where they had the rod and it doesn't have to be. Most things that can go wrong in a differential will be frequency and or load indicated, it will get louder or vibrate in amplitude or make more or less sound amplitude with speed, frequency, changes. There are a few things internally in the differential that can but are not common that can cause it to suddenly bang with acceleration or deceleration. Like the other posters wrote above I recommend that you don't jump to conclusions about it, take the drive line slip joint apart and grease it first. If you have difficulty with that dont even consider trying to rebuild your differential which I think is an 8 out of 10 difficulty job. I doubt that it would be a bad drive line center bearing or it would roar all the time just change amplitude with speed. Check for loose parts everywhere if you have not already. Assuming that you have a Sterling 10.5 inch differential if it is the internal parts of the units differential it doesn't have to be the ring and pinion alone there are several other things internally that can cause what some would call a banging noise. Drop the inspection pan on the differential and take a look, might be something you see easliy that takes the mystery diagnostics out of it. Rebuilding one of these rear gear sets is something most dealers don't do correctly and like RT suggested above some drive line businesses don't do correctly either. It is not just the pinion shaft crush sleeve washer alone that is difficult to adjust and may take several tear downs to get it correctly set up it is the ring to pinion engagement on axis, there is a washer adjustment for that between the larger pinion bearing and the pinion gear, that one alone can take a couple of adjustment cycles - on-off-adjust-assemble. There is also the ring gear adjustment perpendicular to the pinion for lash and engagement that is done with large shim washers behind the differentials two side carrier bearings. It all has to work together to be "correct" More put together-take apart-adjust and start over cycles. Most dealers will just slap it together and if it doesn't make noise right away then they let it go, they are not going to fine tune it, they don't do many and can't tie someone up on it that long.
Is it worth it you wrote, well that is subjective. Money wise the rebuild parts alone will likely cost you $1000 bucks, Maybe a little less if you bargain search. You will need a place to work on it, tools, jacks, torque wrenches, a press, one or dial indicators, a 0-1 inch outside micrometer and a very strong back to work under the truck unless you have a lift. You will have to be creative in building something to get the bearing outside races in their fits. Dealers, look to pay 1000 and up plus parts cost to get a complete rebuild and you get what you get. Drive line shops depends on the shop.
So, look around and try the simple stuff first. That I know is worth it. Good luck, 106

[jeffzielin]

Thanks Oneof6 and to everyone else. I'll check the slip join for sure and let you all know what I find. Is it uncommon for something to go bad in these diffs. I understand the sound transfer and how it can fool you but unfortunately for me not only can you hear it with the rod but you can also feel it as well. The noise only happen under throttle pressure and goes away when you let off. As I said I will do some checking here today in Sunny Michigan where the temp is 16 degrees. Uggg! If I don't find anything conclusive I am stuck at the mercy of The Ring and Pinion Shop here by my house. There are only a couple of places around my home that work on these and it did come recommended from a good source. As I said I am a motor head and could do this if I had a step by step guide but will probably take it in anyways after I do some checking of my own. Thanks to everyone for their help. As always this site has come thru once again. You guys are awsome! Thanks!

[Greg03PSD]

I have a step by step guide (with pictures!) that I made on how to replace a differential (factory LS to ARB air locker), but it doesn't show how to replace the ring and pinion since I reused my gears. Swapping the differential is really pretty easy to do as long as you reuse your original gears. If you can narrow down your noise to something that doesn't require removing the pinion, then my guide will work for you. I have never tried setting up a new gear set, but I have replaced both my differentials with air lockers. If you don't have to remove your pinion, shimming the differential for proper backlash is really easy to do. You will need a press for the bearings. You also need a case spreader so that you can get the differential in easier when you have it shimmed for proper preload on the bearings. My guide shows you how to make one for under $50 (although you do need a welder).

If you want it, PM me an e-mail address and I'll send it to you.

[jeffzielin]

Okay guys the slip joint was well lubed. I re-lubed it up again. The sound is like a whop, whop, whop.......Pretty constant continuous under throttle pressure. When you let off it goes away. I'm going to try my luck and take it to the Ring and Pinion Shop here by my house. I'm hoping it goes well. I'll let you know what they say.

[RT]

I would express a curiosity to the shop - ask them to let you watch them set the pinion pre-load just because you've always wondered how it is done. Read this first so you'll have an idea how it is really done:

pinion.pdf

[jeffzielin]

Well no such luck for me. I took it in to the Ring and Pinion Shop and they pulled the cover and sure enough I have multiple teeth either chipped or broken on the Ring Gear. $1400 to fix it. I felt pretty good about the guy. I was quizing him on from what everyone was talking about here and he seemed like he knew what he was talking about. He did say it wasn't just slap it together and away you go. He said it took a number of adjustments to get it right. Anyways I just wanted to update everyone. Thanks to everyone for all the help and RT thanks for the info and I will ask if I can watch the pinion load