09-07-2008, 11:54 PM | #1 |
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Gear ratio
Can somebody tell me what gear's came in a 72 gmc 1/2 4x4. Thanks
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Daren 04 Chevy Extend cab 2500HD 6.0 Liter 4x4 71 CHEVY 3/4 4X4 402 BB, th400/np205, dana44/eaton ho52 w/4:10-TOY Rip El Jay RIP BOBBO'S MOM |
09-08-2008, 06:38 AM | #3 |
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Re: Gear ratio
ummm i think there's more than one option
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09-08-2008, 10:48 AM | #4 |
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Re: Gear ratio
Easiest way to confirm is to put a line on a tire and a line on the driveshaft and slowly have someone move the vehicle forward as you count how many driveshaft rotations there are to one rotation of the tire. A little over 4 rotations will be 4.10 gears, 4 1/2 rotations will be 4.56 gears, 3 3/4 rotations will be 3.73 gears and so on.
You can also pull the diff cover, count the teeth on the ring gear and pinion gear and divide or look for markings on the ring gear. Good thing about this approach - you now have a good reason to change your gear oil.
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09-08-2008, 04:31 PM | #5 |
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Re: Gear ratio
ohhhh... maybe you don't know what your list of possible ratios is?
off the top of my head (yukon got most of 'em): 3.42 3.73 4.10 4.11 (thick. not sure if it was an option on our gen) 4.56
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RN U OVR Last edited by Senator350; 09-08-2008 at 04:31 PM. |
09-08-2008, 04:46 PM | #6 |
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Re: Gear ratio
If it came with a 350 cid engine, it most likely has 3.73s. If it came with a 307 or a 6 cylinder, it most likely has 4.10s. Any other ratio would be rare to find in a half ton.
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Tim Last edited by Blazer1970; 09-08-2008 at 04:47 PM. |
09-08-2008, 04:52 PM | #7 |
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Re: Gear ratio
Don't forget 3.08's, that's what mine has.
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2006 Jeep Unlimited IMPACT ORANGE 1993 Chevy 2500 4x4 ExCab LWB 454/NV4500 Tow rig 1977 Ford F100 2x4 LWB 1st truck I owned, still have it!!! 1979 Ford F150 4x4 SWB Built Ford Tough!!! 1971 Chevy Blazer 350 / SM465 / NP205 UNDER CONSTRUCTION Soon to have a LQ4 6.0!!! |
09-08-2008, 06:33 PM | #8 |
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Re: Gear ratio
Thanks guys. Have had the cover off. Counted 43 teeth on the ring gear, but couldn't find a gear to match. At least one that matched what would have came in our trucks. I try what yukon mentioned. Wanting to sell front and rear diff's, so i figured i would check them.
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Daren 04 Chevy Extend cab 2500HD 6.0 Liter 4x4 71 CHEVY 3/4 4X4 402 BB, th400/np205, dana44/eaton ho52 w/4:10-TOY Rip El Jay RIP BOBBO'S MOM |
09-08-2008, 09:07 PM | #9 | |
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Re: Gear ratio
Quote:
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09-09-2008, 08:38 PM | #10 |
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Re: Gear ratio
Nothing. There out of a truck i scraped out. Just sitting around yard.
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Daren 04 Chevy Extend cab 2500HD 6.0 Liter 4x4 71 CHEVY 3/4 4X4 402 BB, th400/np205, dana44/eaton ho52 w/4:10-TOY Rip El Jay RIP BOBBO'S MOM |
09-10-2008, 06:48 PM | #11 |
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Re: Gear ratio
Well i counted the rotations and it was 1 1/2 to 1. Gotta be a 3:08.
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Daren 04 Chevy Extend cab 2500HD 6.0 Liter 4x4 71 CHEVY 3/4 4X4 402 BB, th400/np205, dana44/eaton ho52 w/4:10-TOY Rip El Jay RIP BOBBO'S MOM |
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