gear ratio
- Thread starter 58fl
- Start date
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dsteelejr
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- Hudson, WY
- First Name
- David
- Truck Year
- 1973, 1980
- Truck Model
- Cheyenne super C20 camper special, Sierra K25
- Engine Size
- 350, 454
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.
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- First Name
- Andy
- Truck Year
- '77, '78, '79, '84, '88
- Truck Model
- K5 thru K30
- Engine Size
- 350-454
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.
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.
SquareRoot
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- 350
For the one millionth time, pull the cover and look. It needs a fluid change anyway.
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- Green Bastard Parts Unknown
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- Jay
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- 2001
- Truck Model
- pontiac aztek
- Engine Size
- 3.4
If the axle hasn't been replaced, it's a 3.73 non-locking.
Old Guy Bill
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I’ll wager they are 4:11…
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- David
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- 1986
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- Engine Size
- 10 yrs Air Force
this is the quickest and easiest method.
