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| | | | Joined: Mar 2011 Posts: 204 'Bolter | | 'Bolter Joined: Mar 2011 Posts: 204 | i read the tech tip "need for speed" and was ready to begin my gear swap. in the article it says to check pumpkin for "10-41" stamp on it. my pumpkin doesn't,it has "3838365 gm 9-37 1967 2 1" will this work? what is the ratio? the man i bought it from told me it would work. i just want to clear any doubts. thank you ,brian
Last edited by 66flea; 02/26/2015 4:38 PM.
| | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | So the ratio there would be 37/9 = 4.11. Apparently they also made a 4.11 ratio besides the 4.10. Does the outside look exactly like yours? | | | | | Joined: Mar 2011 Posts: 204 'Bolter | | 'Bolter Joined: Mar 2011 Posts: 204 | it does but i never put them side to side | | | | | Joined: Mar 2011 Posts: 204 'Bolter | | 'Bolter Joined: Mar 2011 Posts: 204 | i just went under my truck and they look the same (the new one in question doesn't have a side plug, my old one does) casting numbers on the new one are: 3883379 side, hw03206 top, 3883354 near shaft. cast numbers on my old are: 8699535 side | | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | Apparently they also made a 4.11 ratio besides the 4.10. I'll have to do a quick check to be sure which is which, but one of those is for a Spicer 60 instead of the Eaton.
Bill Burmeister
| | | | | Joined: May 2001 Posts: 1,904 'Bolter | | 'Bolter Joined: May 2001 Posts: 1,904 | One source says the rear ends with an "HW" code were 4.11's from '67-'69 C-20's. Could that correspond to your "hw03206"?
They apparently switched to a 4.10 in '70.
Still don't know if it would work for you.
I got this from the "Chevrolet Pickup Red Book." 1946-1972 Chevies by the Motorbooks International company (published 1993). I know there are some mistakes in this book, mostly omissions. It is kind of useful, though. I don't remember the book being mentioned in the forums.
Last edited by Wally / Montana; 02/28/2015 12:02 AM.
1948 3/4-Ton 5-Window Flatbed Chevrolet 34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
| | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | This might be a bit of a red flag. The "side plug" is actually an adjustment on a part that protects the crown gear assembly from flexing. That is part of the design of that rearend. Has anyone seen that rearend without that feature? | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | As I recall, some 3/4 ton GM Trucks had Spicer rear axles, Chevies had Eatons.
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | That is for the most part, correct. GMC did use Spicers pretty much exclusively. With Chevrolet, though, it depends on what the options were. Generally speaking, 3/4 ton coil spring trucks had the Eaton, and leaf spring trucks got the Spicer, which is how GM lists them in the specs on the Heritage site. However, I have heard of sightings of leaf spring Eatons and coil spring Spicers. Also, GM does show a listing for a 1/2 ton with the Spicer rear and coil springs, but only with the 396 engine.
Bill Burmeister
| | | | | Joined: Nov 1995 Posts: 5,714 62401 | | 62401 Joined: Nov 1995 Posts: 5,714 | We just updated the tech tip with some excellent info provided by Barry Charon on the different trucks and which ones to look for. Check it out!
~ John A kid raised on Hotwheels, Matchbox and Tonka cannot be reasonably expected to own only one vehicle as an adult. 1949 Chevrolet 3804In the Legacy Gallery | In the Gallery Forum1973 IH 1310 Dump1963 Kaiser M38A12001 International/AmTran RE3000 "Skoolie"2014 Ford E-350 4x4 (Quigley) | | | | | Joined: Mar 2010 Posts: 10,271 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,271 | Barry Charon helped me out a bunch on some crazy 4X4 AD options. He has a lot of knowledge and is willing to share it.
Carl
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Mar 2011 Posts: 204 'Bolter | | 'Bolter Joined: Mar 2011 Posts: 204 | | | |
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