The Stovebolt Site Forums The Shop Area Driveline High speed gears

Does anyplace like Summet or Jegs sell ring&pinion sets for my truck?1958 GMC1/2ton.Patrick's seems atad high.I think I have the 6cyl, 3.90 rear , 3speed manual BW OD setup.Didn't know if it would benefit me any?
Thanks,

A 3.90 rear ratio is perfect for your overdrive. You don't need a higher ratio.

Any higher gear ratio will be too high to use the OD, and no, there are not any other sources for the 3.55 gears. They're all made by a single supplier in China, I believe. Mothertrucker has a better price than the other vendors for the same gearset since he made a volume purchase from the manufacturer. A better price won't make the gears work any better with an overdrive transmission. The engine doesn't have enough torque to pull the higher gear in OD.
Jerry

Ok thanks guys

MT still has the best price around on the 3.38:1 gears for the 1955-1962 1/2 ton trucks.....

http://www.jalopyjournal.com/forum/...-ton-truck-3-38-1-highway-gears.1013374/



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would the Chevy 3.38 gearset even work in a GMC rear? ... I thought the 5-9 GMCs had a factory 3.07 rear gear

Bill

MT just said that they only offer gears for Chevy trucks.

They Do Not get involved with parts for the oddball GMC trucks.

And he stated that he was under the impression that the 55-62 GMC's used 3.90 gears originally & the weird 3.07 gears were only used in Hydramatic equipped trucks.

I don't support it.... I only report it.

I believe the 3.07 is a Spicer rear end. These gears will not work in a Spicer.

It seems to get somewhat confusing as to what you might find under a GMC 1/2 ton. Even the factory literature contradicts itself. I've found one that lists the Spicer 45 as the 3.07 and the HO33 as the 3.90 depending on option, but another source that only lists the Spicer in 3.07 and 3.92, again, depending on option. Both were factory literature.

Is the Spicer rear different than the Dana 45? When did Dana and Spicer merge? (just curious)

Thanks, Dave... so, is the spice rear end different than the Dana 45? (45 is what was stock in my 59 Suburban)

Dana and Spicer are two names for the same company. The Dana type 45 is a real oddball- - - -very limited production and repair parts are unobtanium. It's possible to use a Type 44 ring & pinion gear if the rest of the parts are good, but things like axle shafts, side gears, etc. are different (heavier) than the type 44 which has been used in dozens of applications- - - -GMC, Ford, Dodge, International, Jeep, etc. cars and trucks.
Jerry

They did.

Ed

Notice the wikki post doesn't mention the 45!

Yes, it does, but it's a very short reference. My 59 Burb had one, which ate most of the internal parts after the pinion nut came loose. I replaced it with a 3/4 ton Dana 60 unit that one of my fellow racers gave me. It had 3.73 Ford gears, a GMC housing, and a Dodge pinion flange in it by the time it was road-ready. It also had 8-lug rear wheels and a 6-lug 1/2 ton front axle.
Jerry

From Wikipedia.

The Dana 45 was introduced during the 1950s as an upgraded Dana 44 with larger 20 spline axle shafts. Since the Dana 45 is no longer being made you can use the Dana 44 gears in the Dana 45 housing if you use model 53 pinion bearings and lots of shims.

Spicer 45 in its one Chevrolet application. It was used in '59 for trucks with the Positraction option. The Eaton Positraction for the HO33 came out the next year.