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| | | | Joined: Jul 2003 Posts: 101 Wrench Fetcher | | Wrench Fetcher Joined: Jul 2003 Posts: 101 | May buy a G506. From research it looks like the Diffs are 6.51, TC is 1.94, but I can't find anything on the tranny. I've seen it called a GM Corporate Spur-gear or Sliding-Gear transmission.
Does anyone know for sure what the tranny and ratios are, in particular the granny gear ratio?
Also, seller said he thought that the 235 in military trucks had a pressurized oil system instead of just a splash type. Anybody know four sure?
Thanks
| | | | | Joined: Mar 2004 Posts: 6,214 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,214 | What year truck/trans are we talking about? Mike B  | | | | | Joined: Jul 2003 Posts: 101 Wrench Fetcher | | Wrench Fetcher Joined: Jul 2003 Posts: 101 | | | | | | Joined: Jul 2003 Posts: 101 Wrench Fetcher | | Wrench Fetcher Joined: Jul 2003 Posts: 101 | Dug up this site with old repair manuals. It's probably old news to you guys though. http://chevy.oldcarmanualproject.com/military/1942/index.htmAnyway, it doesn't identify the tranny but does give the ratios as follows: 1st 7.06 2nd 3.48 3rd 1.71 4th 1.00 Rev 6.98 I believe the later SM420 has a 7.02 granny | | | | | Joined: Dec 2010 Posts: 253 Shop Shark | | Shop Shark Joined: Dec 2010 Posts: 253 | If it is the original 235 that came in the truck then it is a babbit bearing, splash oil motor. The only way it would be full pressure would be if someone pulled the original motor and put a later one in. The cckw or "Duece and a Half" was built by GMC and the motors in those trucks (270 cu in) were of a more modern design the Chevrolet 506's used basicly a bigger version of the 216.
-Mike-
Last edited by sleeve; 07/11/2012 6:49 AM.
1945 Chevrolet G 506 1.5 Ton Military 4X4
1967 Jeep Cj5 with 283 SBC
| | | | | Joined: Jul 2003 Posts: 101 Wrench Fetcher | | Wrench Fetcher Joined: Jul 2003 Posts: 101 | Found some more ratios for the Diffs and TC on this website and another. http://www.stovebolt.com/gallery/lampman_greg_1942.htmlThis Stovebolt article reports a diff ratio of 6.67 and TC of 1.94 and granny of 7.06. 91:1 -- Woohoo! He is replacing the orig tranny with a NV 4500 5-sp with ratios of 6.04, 5.6, 1.67, 1, 0.73. The 1942 military 4x2 manual linked in a post earlier in this thread shows a Diff ratio of 6.17 with an optional 5.43 diff. Of course this manual is for the 4x2. | | | | | Joined: Jul 2003 Posts: 101 Wrench Fetcher | | Wrench Fetcher Joined: Jul 2003 Posts: 101 | Sleeve
Thanks for the info on the 235. Seller says that someone told him it might be a newer 235, a 1952, but I thought the pressurized 235 didn't come out until 54.
Yep, wish it was a Jimmy. I've got a 51
GMC 1-ton with a 302.
If I buy the 42 it'll probably never see another 100 miles. Will just pull stumps on my mountain property in Silverton, so a 235 will be OK. | | | | | Joined: Dec 2010 Posts: 253 Shop Shark | | Shop Shark Joined: Dec 2010 Posts: 253 | Sleeve
If I buy the 42 it'll probably never see another 100 miles. Will just pull stumps on my mountain property in Silverton, so a 235 will be OK. In four wheel low these trucks are unstoppable.....your stumps wont stand a chance. :>)
1945 Chevrolet G 506 1.5 Ton Military 4X4
1967 Jeep Cj5 with 283 SBC
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