1938 Coupe rear axle width

[Dusty]

I'm getting ready to swap out the GM 12 Bolt in the '38 Coupe, and I can't remember what the
width is, backing plate to B.P.  I just had a total knee replacement on my left knee, and can't quite get down that low to measure the width.  Anyone remember what the early Chevy's were?

Thanks,

Dusty

[Dusty]

OK...I had a buddy come over today, and he crawled under the coupe, and came up with a Backing plate to B.P. measurement of 52".   Spring perch was 43".  What Ford rear axle comes close to this?

Thanks

[enjenjo]

Backing plate to backing plate is not a very usefull measurement, as different brake widths will change this by as much as an inch per side on the same width diff housing.

That said almost all 12 bolt rears were about 60" wheel mounting face to wheel mounting face or there about. The early Nova 12 bolts were the only one that was narrower, at about 57"

The original 38 rear was about 60" wide also. I do know that back in the day, we installed a 57 Ford rear in a 37, 57.5" wide, and had to use reversed wheels to make it work. I am guessing a 70s Torino rear at 60", or a 61 to 64 full size at 61" or a 69 to 70 Mustang at 60" will be pretty close.

[Dusty]

OK Frank...
Thanks for the info.  I must have one of the early Nova rear axles in the coupe now.  Another person wrote that Mustang from 67-74 were just about the same width, and the spring perches were the same.  He claimed that you could measure B.P. to B.P., and add 5-6 inches and come up with wheel flange to wheel flange.  Any way I'm going tomorrow to look at some rear axles.  A parts yard owner said he had a pile of housings, and a rack full of axles.  If I pick a housing that's close to what I need, how do I know for sure what axles go in it.  Ford had so many different lengths.  Is there any numbers stamped on the housing like the GM housings?

Thanks,

Benny

[enjenjo]

No numbers on the housing. The ID number is on a tag fastened to one of the bolts holding the center in place.

If he has the housings marked with the Hollander interchange number, you can use that to cross reference the axle lengths. Barring that, you can install a center section in it, insert a 1" dowel until it bottoms out on the differential pin, mark, and measure the dowel from the end of the housing to the end of the dowel, subtract 1/8" from that as the length of the axle from the outside of the bearing to the end of the splines. next, you need to know if it is a big bearing or small bearing on the axle. Big bearing is about 3.1" diameter, small bearing is about 2.87" diameter. Next, you have to match the bolt pattern on the end of the housing to the axle retainer. there is two possible bolt patterns on the small bearing, and three on the big bearing. Finally you have to match the stand off on the outer axle to the bearing. some are 2 3/8", and some are 2 1/2"

There is also the wheel bolt pattern to take into account, there are three 5 lug patterns, and two 4 bolt patterns possible on axles that will fit a 9" rear. 4 x 4.25", 4 x 4.5", 5 x 4.5", 5 x 5", and 5 x 5.5"

And three hub pilot diameters, 2.75, 2.875, and 3.125.

Finally there are two axle spline counts, 28 and 31

On the brakes, there are 9.5", 10" and 11" brakes in drum, and two possible disc configurations. each one needs different backing plates with the right bolt pattern for the housing, and hub offset to fit the axle.

What you could do, it buy a housing that is too wide, spend $60 to get the hybrid ends that Moser makes, that fit a Ford large bearing with a Chevrolet backing plate bolt pattern, have it shortened to what you need locally, and a pair of Moser axles for a Ford with Chevy bolt pattern, and their hybrid end, then you can use the brakes, and wheels you already have.

[32 Chevy]

Hi,

If you havent found a differential yet, I have one that Might do the trick. It's a Ford 9" out of a 78 Linclon Versailles. It has the factory disc brakes and is 56" hub to hub.

I was going to install it in my 56 wagon but plans change.....

Dave R

[Dusty]

Where do you live Dave, and what shape is it in?  
The Guys here are finding parts rather hard to locate for the factory Ford/Loncoln discs.
It may be too narrow.  
I'm getting some help tomorrow, and we are going to pull the back wheels and get a Hub to Hub measurement.
What do you want for it?

[32 Chevy]

Actually its bit of a story how I got this differential...

One day I was driving along I -5 and saw a lincoln Versailles on the back of a wrecker's flatback. So, as any self - respecting rodder would do I followed the truck all the way to the wrecking yard. I then claimed the differential before they dragged it to the crusher.

Knowing how rare these 9" Disc rears are, I personally  pulled it to make sure nothing was damaged, especially the  E brake components that are made of unobtanium. It's all there, undamaged, even the e brake cables. Actually the dust shields are bent a little but those can be hammered flat easy enough.

That was several years ago and it has been outdoors so it is rusty and needs the usual overhaul you would do to any unit from a yard.

I was going by memory when I gave the previous dimensions... I just measured it and the width is 58 1/4 hub to hub, 43" between perches. The gearset is 3.0 open.

I'm in the Seattle area ... I work with several shippers and could send it to you. Price? Geez, I dunno, never thought about selling it until I saw your post. If you think it will work for you, shoot me an e mail and lets discuss. dave@ghboats.com

[enjenjo]

Dave, what ever happened with Kyle and his pickup?

[32 Chevy]

Hi Frank,

Wow, you have a good memory... There has been a lot of water under the bridge since then.

Kyle has grown up to be one of those young folks who give us confidence in the future. He graduated from the university of Washington with a degree in hydro geology and got a great job in his field. He still gives thanks to RRT and the encouragement from here.

He also gives a lot of credit to his getting the first job to what he learned building the truck.... He was the only one of all the candidates who could instantly answer correctly "what is a grade 8 bolt?". That answer got the job!

The truck resides proudly in his Grampas garage and is his favorite possession. He say he will Never sell it, too many good memories.

Dave

[enjenjo]

Glad to hear that.It makes your heart warm to think you might have helped a young guy.