The Stovebolt Site Forums The Shop Area Engine Shop ring and pinion id help?

Can anyone help me with the applications for GM #3748437 ring and pinion set? Box says 57-58 with automatic. I need to know if this will be for a car or truck differential. I looked in my '46-'72 Chevrolet truck Master Parts Manual but could not find it.
Thanks for any help with this.

Where is this number stamped or casted?

I don't have the gear set in my hand, because I don't know if they would work in a '55 first series differential housing. That is the number on the box. Parts Manual I have states they were sold as a matched set same number for both ring and pinion. I had heard of a truck fuel saver option ratio offered in '58, but lack any more information or part number for it. Patrick's now offers a 3.38 set for '55 and up trucks, around $400. I have a price for this nos set a lot less. But will they work???? :confused:

If anyone out there has one of those rare late '50s Master Parts Manuals, this part number would be listed in 5.529 Gear Assy..

My Master Parts Book covers through 57. No number that high for ring & pinion.

I sure wish I could get a second opinion from a '59 book. The application would cover 55-59 differential housings in the half ton. Thanks for looking. :confused:

I have all these Factory Chevrolet Service News Bullitins that were give out to the factory mechanic and this is what it say's about the rearend gears for the 58 truck. "Series 31 and 32 carry the 3.90:1 axle ration of previous models as standard equipment. An Optional axle of 3.70:1 is now available" Is this the fuel saver option??

I looked in my Interchange Manual and thought that I found that number you indicated but it's one number shy. I found 3748436 which is for a 53-55 3.55:1 gears in a Corvette and sold for a sum of $46.95

I looked a little more in my Interchange Manual and found the 3748437 gears are a 3.36 Ratio and go to the 56 Corvette although they will interchange with the other 50-62 Vette's by using the case. I don't see that number 3748437 crossing over to work in the truck rearend.

that rear end could be worth somthing to sombody restoring a corvett

Thanks for the help on this! I had suspected they were probably for a 'vette. They did not sell or meet the reserve price around $125. Since Patrick now sells 3.38 gears for the 55-59 trucks, I thought these might work. I'll be happy to pass on the information to anyone who may need them.

Your very welcome for the help. Thanks for the question, it gave me a reason to open up the Interchange Manual my Uncle gave me as well as the binder of Chevrolet Factory Service News Bulletins I purchased at an estate sale for a $1.

Hay, while you got the BOOK handy, does it show anything taller than 3.90 for the 1/2 ton '55-59?

Here is what the book shows for gear ratio's

For GM Built H0333 Axle
A)
3764960......3.36 Ratio
3749020......3.70 Ratio
3747808......3.90 Ratio
Chev Tr 55-5u 1/2 T Conv
Chev Tr 58-59 1/2 T Conv Non-Locking Axle
Chev Tr 60-62 10 Series (1/2T Conv)
GMC 55-56 (Y,X) 1/2 T Conv

B)
3747809......4.11 Ratio
Chev Tr 55-57 1/2 T Conv
Chev Tr 60-62 10 Ser (1/2 T Conv)
..............................................
For Spicer 45 Axle

2354371.....3.92 Ratio
Chev 58-59 1/2 T Conv Locking Axle
GMC 56-59 (X,T,S) 1/2 T Conv

seems like that 3.36 [or the 3.38 around nowadays] would need a/the 4 speed to be really usefull - what's the ratios on the 3spd and where does one find the ratios of the saginaw 4spd? [Tony?]

Bill

Patrick Dykes has a rundown on this he put together for uses of the 3.55 ring and pinion. No doubt he now has one for his 3.38 set as well.