The Stovebolt Site Forums The Shop Area Engine Shop searching for 49 3600 rear end info

I just spent an hour searching but have not came up with much info. Hoping someone can point me in the right direction. I'am trying to find out what my options are for changing the gears in my 49 3600 rear end. What has anyone else done? Are there any ring and pinions (I tried Patricks and Randys ring and pinion)that are available or is there another model 8 lug axel that will fit?

Thanks in advance

Chris

This has been addressed a number of times. You will probably have a ratio of 4.57 in your truck. There are direct bolt-in "pumpkins" or the complete gear assembly of the rearend from 3/4 Ton GM truck from 67 to 72, with automatic transmission, that will give you a 4.10 ratio. If you go on the Jim Carter site, he has a technical description. The only tricky part is finding one. I put one in my 1 Ton and it works really well. You can do a search for "410 gear" and you will get a lot of hits.

A 5.17 ratio was an option in 3/4-ton trucks and standard in 1-ton trucks. You are not clear which direction you are trying to go...

If you need something more highway friendly than 4.11 you probably need to swap rears. I've been told there is a 3.something out there, but no one ever seems to be able to find one.

I'm not sure what else would fit, but if you take a tape measure to the wrecking yard you should be able to find something close to the right width.

You're pretty well stuck with those low gears unless you swap rears with something later that will fit your 3/4 ton.

Thanks for the info I will try that.

Yeah trying to find something more road frendly, told now there is 4.56 gears in the truck.

Thats what I was afraid of.

I swapped to a 81 Camaro 10 bolt. Of course your lugs won't match your front. If that is a problem you can either install a mustang II or weld on a clip that gives you 5 lugs. There may be a kit to swap your 8 lug to 5. It seems like I remember a discussion on that here in the past. Someone will be along to answer that question i am sure.

Try searching Dana rear ends. I put a dana 60 with 3:54 gears in my 3600. Some did come with Dana rear ends. I wanted to keep it a 3/4 ton so I went that way. It was a simple bolt in with minor mods. Kept the 8 lug configuration.

That Camero rear end should be the standard 5 lug Chevrolet bolt pattern. If you can give me the casting or part number which is cast on your front axle, I might be able to give some options regarding the front axle and matching it to a Camero rear axle. That casting number is on the front or back face of the axle on the flat between the top and bottom part of the "I". Matching five lugs all the way around shouldn't be too bad if you can get some decent rear gears.
Joe