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Trying to get up and running to drive the MVPA convoy in Ohio. Pulled the rear pinion carrier to find the ring gear badly pitted. Then pulled both parts trucks rear carriers and they are also pitted. How much can I get away with? The plan was to sleeve the pinion flange, turn an adapter on the lathe and install a new production pinion seal. Now I've got a project. Also the carrier from my 37 was missing the nuts from two of the ring gear bolts. The keeper tabs were bent up, but no nuts!

Sunset,
Is this truck going to be a daily driver, or something you are going to put a gazillion miles on? Or is it an ocasional drive to the hardware store on Saturday, or the ocasional Rally or parade? By the book, you should probably replace the pitted r&p. In reality, it will probably out last you! Might make a little more noise, but again, how much do you plan to drive it?
My rear diff had broken axle chunks the size of half a hot dog in it. It had also sheared off a few of the ring bolts and keepers. I cleaned it out, inspected it thoroughly and replaced the nuts and bolts as well as the thrust pad and bolt. Other than that it was fine, I got lucky. Who ever replaced the broken axle didnt do a very good inventory of the broken pieces.
Tim

Thanks. I decided to pick the best of the 4 that I have taken out of the 3 trucks. Last night it got speedy sleeved and a NOS seal and will install today. This is the short-term answer because I plan to make a daily driver. I have a rebuild kit, and as soon as the budget allows will buy 4.89s and make it right with a better rubber seal for the pinion. Now on to the leaking transfer case!

Obviously water has been in the unit or the rust pits wouldn't be there. Did you pull it down & look at the bearings? They are most likely pitted just like the gear teeth & the pinion yoke.

The real deal is this, once these areas become pitted, that means rust has eaten its way through the relatively thin hard surfaced layer on both bearings & gear teeth. Once the hard surface begins to break down as is obvious in your case that is already well underway, the rate of wear is GREATLY accelerated. Truth is it may last a while, or it may not last an hour, nobody can answer that question. This is for sure, it will never be a dependable set up, you will always have to wonder every time you hit the road; will this be the day catastrophic break down will occur? It will eventually occur.

The pinion seal issue, NOS leather & felt seals are a killer. That felt area draws moisture like a sponge keeping the area of the yoke it mates with wet. Rust pitting is a sure thing in a short while. We never use NOS seals as they will ruin a good yoke in short order. The best seal on earth will not hold oil if mated to a pitted shaft. The leather causes grooving over time & even on a good yoke surface will always seep & drip oil.