The Stovebolt Site Forums The Shop Area Engine Shop Help Identifying Rear Diff

In another thread I asked a question about my rear diff. The outside says "1970 Chev PO. 3:73" What that means and what it's from, I'm not sure. So on the advice of Big Chevy 3600, I cracked her open and took a looksie.

Pictures here: http://good-times.webshots.com/album/561560754mpOVmk

There isn't anything obviously wrong with the gears, but I don't really know what to look for. The fluid was dirty. I could tell that, so I'm glad I cracked it open. It gives me a chance to change the fluid.

So, what do I have? Also, it always warms my heart to find cut hoses. There were a lot of them on this truck. What does this one go to? It obviously went somewhere on the donor vehicle.

Thanks. One step closer to undoing to the hacks done previous owners.

This is not the site I was looking for, but it does show your axle to be a GM 12 bolt.
http://www.coloradok5.com/axleguide.shtml

Grigg

The descript. sounds as simple as a '3:73 posi.'

Ken

Thanks for the info. I thought it was a posi. My guess is that it came from a 1970 C-10. Anyone have any ideas about the cut hose?

Its hard to see with the pics, but Ive seen several rear ends with a longer rubber hose coming out of the top of the differential and dropping off to the side. Id say its the vent for the rear if it does.

Jeff

If it is a simple rubber hose stuck on a push on barbed fitting on the axle housing or tube then I too say it's a vent. It should have a vent looking widget in the other end of it and that end is usually clipped inside the frame rail above the axle.

Grigg

66 Bowtie if the pic you have posted are the rear you are talking about it is not a posi unit in the pic. The hose should be the vent though.

Definitely not a posi in it. Can't see where the hose comes from, but if it's from the top of the axle, then very likely the vent.

Somebody might have used this as there "mudder" truck axle. You run your vents up high to avoid getting mud and junk in the axle.