Best rear end for '37 Chevy

I just bought a project to be a daily driver for my wife. I want to put a later model rear end under it. What width rear ends are you guys running in your '37s and what gear ratio would you recommend for just a driver that wants to get good gas mileage and not necessarily be super fast. Of course, we don't want it to be so high that it lugs around town and gets bad mileage there.

I hear a lot of guys running Ford rear ends under these cars.

Brandon

 

rear and gears would depend a lot of what motor/trans youre going to run in it too

 

Oh yeah, good point. We've got a 5.3 GM LS and a 4L60E trans to go in it.

Thanks,
Brandon

 

68-72 nova 10 bolt under my 38 coupe. Ch***is Engineering makes a bolt in kit for this rear end in 37-38 chevys.

 

I have a Versailes rear in my 38 chevy. Had a little problem with clearance between the frame flange and the emergency brake levers. Granada 8" or 9" work good as well as chevy II. 4x4 S10 are the right width also. I'd go with a rear in the 3.25 to 3.50 range.

 

For best performance & economy you should keep as close as possible to the factory rear ratio that went with the engine, transmision and computer. That is, if you are keeping the computer.

 

Thanks for the info guys. I'm going to have the computer reflashed, so I can use whatever rear end ratio would work best.

Thanks,
brandon

 

I have a 8" Ford Granada in my 37, width is perfect.
3.55 ratio woks good but I have a pretty tall rear tire.

 

You don't say what the engine/trans came out of, but the gear ratio in my '92 Buick Roadmaster is a 2.56:1. the stock cam is a low RPM high torque cam. Anything like a 3.55 rear in that is going to kill the 30 mpg @ 75-80 cruise. A computer can do some tuning but it can't make brute force design changes.

 

Sorry, I thought that we were building hot rods.
Mine runs about 2200 at 70 MPH with a Muncie 4 speed.

 

also tri-5 rear ends bolt right up the the original leaf springs in these cars. i always thought that a 235, t-5, with a 55-7 rear end would be a cool combo for a pre-war chev..... it would get good mpg and with the t-5 you could still run a good rear gear for getting out of the hole, and still be vintage.

 

I've got a 40 chev. coupe with a 700r4 and a tri-five stock rear end--3:56 ratio. For just pure driving and decent fuel economy, this is a good combo.
It has a pretty good jump also, but, as most everyone knows, the old tri five rear ends are weak and now a good one is hard to find. I've heard a Ford 8.8 is the trick setup now.
cooger

 

Yes. That Buick driveline makes for a very interesting ride when transplanted into a lighter, older car. I collect them for that purpose.

 

The ford 8.8 from the Explorer is a good choice, they are 59.5" wide from wheel mounting surfaces. They are strong, easy to find, inexpensive, and have disc brakes. The 3.50 and 3.73 are the most popular, and easily found with track-lock. For good low end and good fuel milage the 3.73 is very popular for that engine-trans. you have. The 3.50 will drop the low end a little and increase the milage.

 

Thanks guys. I found a couple 3.55s, but I found out they had 3.08s as well. I think a 3.08 would be pretty good and still not be a complete dud.

Brandon

 

3.08 might be to high of gear ratio for a overdrive. 3.55 would be as high of gear ratio that I would run. If you run to high of rear end gear the engine will lug and the transmission will not shift right.

 

'69 Olds cutl*** 12 Bolt w/posi in my 38 coupe. 3.42 gears.

 

What size tire are you using?

Personally, with that engine I'd probably gear it for around 2200RPM at 70mph. You're carrying a thousand pounds less weight than a 1500 Silverado but pushing about the same amount of air down the road.

A 3.50-ish rear would be a pretty good guess with the 0.70 fourth in the 4L60E, but it depends on your tire rolling radius.

Not sure what width you need but the Explorer 8.8 can be centered by shortening the long-side tube and scrounging another short-side axle, ends up around 58in over the axles flanges IIRC, most are 3.55 or 3.73 Trac-Loks and bring along a nice disc setup, of course the Explorer axles are 5x4.5 bolt circle. Could probably redrill for 5x4.75 but a 6-bolt pattern would be hopeless w/o new axles.

What are you doing up front? What's the bolt circle on that car? Are you changing it?

I eventually need to find myself a set of 6x5.5 Huck rear brakes for a project, if anyone's throwing a set away...

 

I just put an 8.8 in my 36 chevy, had elpocko shorten the long tube and went with two short axles. You can get an open rear cheap for the short axle. I think its 56.5 wide now but my mind is foggy. Mine is 4.11, track loc, 31 spline, disc, all really cheap. They claim its similar to a 12 bolt chevy rear. The older ones had drums. Get the explorer rear and not the ranger, they are only 28 spline.

 

I'm with noclubjoe post#4 on this rearend solution. I installed a '74 Nova 8.5" with 3.42:1 ratio posi behind a 200 4R automatic. I wish now I had a 3.73 ratio because at around 45 mph on country roads the 3.42 causes the ****** to shift into .67 overdrive.