Spring Perch Measurements

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AGSheep

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B
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Looking to swap the 10 Bolt in the back of my '89 Suburban 1500 to a 14 Bolt Semi or FF.
Would prefer to have it bolt right up so looking for something with similar leaf spring perch measurements.

Problem is, all the information regarding measurements seems to be all over the place.

One site will say that all 1/2 ton and 3/4 ton axles have the same 42.5 perch measurement. Is this just for the K's or also for the C's?
Some say that a C20 will not bolt in to the rear do to them having the 40.5 measurement, other say that there are 3/4 ton C20s that will.

Easiest thing to do would be to venture to all of these for sale locations and measure them myself, but with gas at almost 6 bucks a gallon and every location like an hour away, it just does not seem cost effective.
 

Traucht

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I thought you were talking about a fishing trip. :cool:
 

AyWoSch Motors

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Looking to swap the 10 Bolt in the back of my '89 Suburban 1500 to a 14 Bolt Semi or FF.
Would prefer to have it bolt right up so looking for something with similar leaf spring perch measurements.

Problem is, all the information regarding measurements seems to be all over the place.

One site will say that all 1/2 ton and 3/4 ton axles have the same 42.5 perch measurement. Is this just for the K's or also for the C's?
Some say that a C20 will not bolt in to the rear do to them having the 40.5 measurement, other say that there are 3/4 ton C20s that will.

Easiest thing to do would be to venture to all of these for sale locations and measure them myself, but with gas at almost 6 bucks a gallon and every location like an hour away, it just does not seem cost effective.
I asked a similar question just the other day, I dont have a clue. Didnt get any easy answers.
Am curious to what the answer is though
 

SquareRoot

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It will NOT bolt in place of your 10 bolt. You have to relocate the spring perches and shock mounts. I've done it many times.
 

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