So the dana 70 in the back of my truck has been giving me problems lately, I cant get the pinion seal to stop leaking, and it is starting to make funny noises. I was thinking of changing it out with a 14 bolt or dana 80 but happend to run across a HO72 for sale in my area. A few questions, can I put 4.10 gears in it? It has 5.13 gears in it now, that he welded, I think it came out of his mud truck. I looked a little online for ring and pinion sets for it but couldnt find any, seems like parts are kind of hard to come by. I read that some 14 bolt parts are interchangable with the HO72 but I dont want to buy it and have it turn into something that I cant use or is going to cost me an arm and a leg to get under the truck. Also he want $400 for it, what do you think of that price?

 

Been done:

https://www.dieseltruckresource.com/...e-t242590.html

 

400$ is way to much for an HO72

You could probly find one in a bone yard for 100$ or so with 4.11 in it already

 

kind of off topic, but not quite. Never heard of that rear end, what the heck is it out of??

 

49-72 GM 3/4 and 1 ton trucks and vans. Its a heck of a stout rear ,Alot of pullers in this area are using it

 

Thanks for the reply. I kind of figured that was too much money, I guess I will start looking in local junkyards. Does anybody make a limited slip for these, or is it a detroit locker or nothin? How can I tell what gears are in it, will there be a tag on the axle or do I need to count R&P teeth?

 

Detroit or nothing, I actually have a Factory Detroit under my old 67 but its stayin there, there hard to find

There might be a tag, maybe, or you could look at the option sheet(Should be inside the glovebox) if its still there and if the rear hasn't been changed over the years, but the best way is yes pull the cover and count and divide. IIRC there might be a stamping in the ring that tells your tooth count also

 

Anybody ever run a detroit in a daily driven truck? Obviously the axle could take it, just worried about tire wear. Eventually I would like to build my truck so I could hit up a few local truck pulls here and there and not have to worry about breaking parts every time, since I drive my truck everyday. Thats what first got me interested in the HO72, it looks pretty stout.

 

Not that bad to deal with. You will have to get used to driving it though. ("Click click boom!") Tire wear isn't too bad for me. I guess it would all depend on where you drive, high way or lots of turns on city streets?
Hope any of that helps!
Justin

 

I ran the one in my 67 for 6 years daily, just let off when you go around corners and tire wear should be minimal. The Detroits are noisy though

 

I second the "click click BOOM" of a Detroit. My best friend had one in his rear end, the first time I ever rode in his truck, I thought we exploded the rear going around a corner. But it was just the Detroit releasing.

 

That's the key. Coast through turns and they are much less obnoxious.

 

Well I went to a local junkyard yesterday and found two HO72's. One had a factory detroit in it but he would only sell it as a pair with the front axle on the truck and wanted $750 for the both. The second one was just laying in a pile of junk and he said he would let it go for around $100. I pulled the rear cover and the inside looked good. I counted 32 teeth on the ring gear, so can someone help me figure out what gear ratio that converts to.