Author Topic: Final Drive Ratio  (Read 2514 times)

Offline Jay2D2

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Final Drive Ratio
« on: January 31, 2009, 07:48:35 am »
Hey guys just wonderign if there was a common rear gear ratio on a 82 k25 with a 400 trans and a 14 bolt 10.5 or did gm have options in that one too

also in relation to the front diff and rear diff do the ratios have to be the same?

Offline zieg85

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Re: Final Drive Ratio
« Reply #1 on: January 31, 2009, 07:56:45 am »
GM offered many ratios.  Check to see if the sticker is still in the glove box which should tell you.  The rear-front diffs ratio can vary but not much.  An example would be 4.11 rear 4.10 front, at least that was the case in my 72 K20.
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline Captkaos

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Re: Final Drive Ratio
« Reply #2 on: January 31, 2009, 11:20:19 am »
There is only one way to tell and know for sure on a vehicle that old, pull the inspectin cover.
Most of the ones I have seen came with 3.73 gearing, but that doesn't mean yours is that way.
The front and rear can only vary 1% for a vehicle that sees highway use.