gear ratio

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58fl

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the numbers on my axle tube is K BH W 178 2 the K may be a R could anybody tell me what the gear ratio is
 

dsteelejr

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Those codes don’t tell you the gear ratio. Your best bet is to remove the differential cover and count the teeth on the ring and pinion gears.
 

58fl

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you are right, remove cover
 

bucket

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If those are from the forward face of the right side axle tube, then they actually do tell what the ratio was. Originally, anyway.

The biggest issue is finding an accurate source to decode them. I believe @RetroC10Sport had the list of those codes for some of the years.
 

58fl

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this is a 1976 k10 350 auto with a 203 transfer and the rear has never been changed, i will pull the cover to check
 

Old Guy Bill

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I’ll wager they are 4:11…
 

Camar068

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Mark the driveshaft and rotate the tire 1 full revolution. Then math.
this is the quickest and easiest method.
 

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