Decoding Axle Codes?

[boot_smart]

Anyone have a link where I can decode my axle codes on my 12 bolt rear end. Ive seen hundreds of links for this one http://www.americanclassic.com/paint.htm but this wont work if you have no idea where the rear end axle came from.

I bought a 68 short-bed from a fellow about 3 weeks ago, that he was making into a rat rod. I saw more potential than the rat rod. So Ive started rebuilding it into a nice show truck.

I ran across a rear axle leak on the hub and its got me looking for where the drive train has come from? Its got a 400 sb in it and a THM 400 tranny, and supposed to be a 3:42 gear in the axle. I know none of this stuff if original.

Im not second guessing about the rear end as it really dont matter what he said. I'll rebuild the seals and bearings and get the ratio from the ring and pinion gear.

But I would like to know what it came out of, same as the tranny and engine there easier to track down but the axle if becoming more difficult to do. Any help would be much appreciated.

If you know any of the numbers it would be great but I dont mind looking up them myself if I can find a place to do it at.

Here's all the numbers I could find on it, on the back of the housing drivers side Con 1 and above that on top is K307. On the front drivers side housing is GM56 and front passenger side NF 3896839 the bold 3 could be a 9. Nothing on the axle tube.

Thanks for any help

Eventually you get kicked enough you become boot smart

[Longhorn Man]

Is this a coil or a leaf rear?
How many lugs?
Got any photos?
You should be able to get a number off the seal if you are carefull removing it, and NAPA can get you a replacement. Same deal with the bearings.

[boot_smart]

Thanks for the reply, it has 5 lug, coil. I just pulled the cover off and got a 3.73 after the 41/11 count on the rings. But after I did that, I decided to go ahead and pull the shafts out and take a closer look at that seal thats been leaking.

After a closer look my first thoughts were correct, its the drivers side seal leaking all in the brakes causing them to smoke like crazy.

That was the good part, if you want to call it that. On closer inspection my drivers shaft was buggered up where the bearing is and looks to me as if it spun a bearing there. So on the phone I got calling auto parts stores looking at replacing the shafts and go ahead replace the bearings and seal.

My local part store tell me go to Summit! They can get it cheaper and a better axle shaft. I take them up on it after calling them up. Away I go 2 hour drive.

Get there and then get to sit for the next 2 hours for them to get the shafts and tell me I didn't pull the seals that I had in my hand out of the rear end I told them about. (12 Bolt 3.73) The say I got the drivers side right but not the left side. Im telling them yes I did, and showed them 2 different size seals, yes 2 and 2 hours later Im walking out $293.00 dollars lighter and only one side of the axle seals and bearings.

Im looking high and low for the passengers seal that for some reason no one has ever seen. I try to get 4 different part store to try to match it up but no luck so far. After 8 hours of searching, I gave up and went home. I'll try again tomorrow,

I'll try to get some pictures seals so you can see the difference in them. I got the drivers side but nothing on the passengers yet. No numbers on it unless you call the micro scopic writing on the rubber part of the seal. I'll need a microscope to read that one. The thing about it is, I got another axle in the yard with the same thing one side of the axle housing is bigger than the other at the very ends where the seals go. Don't figure? Bummed out on a $5.00 seal after $300.00 spent. Anyone ever seen this? 2 different size seals and bearing's on one axle? The inside of the seal is the same size but the outside is different. Both axles have 30 splines and are the same length, and same diameter.

[uncle]

It may have had an axle saver bearing in it . It sits in a different position on the axle because of the same problem you are having now.