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Discussion Starter · #1 ·
OK simple question. My truck had listed on the invoice 3.73 standard with tow package. It also came with the 265 70 17 tires. Now my uncle has a base work truck that came with 3.73; however, his truck came with 235 70 16. His tires are much smaller. So in reality he really has a stepper ratio??? His is a 4.8 regardless but both are NBS and a 4l60E.

So (rambling) the ratio listed is just that, what is in the differential and subject to change between tire size. Otherwise my truck should really be like a 3:42 with the bigger tires.???
 

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If you both have 3.73s, there's nothing different in the differential regardless of tire size. His motor will spin at a higher rpm than your truck at the same speeds.
 

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Discussion Starter · #3 ·
If you both have 3.73s, there's nothing different in the differential regardless of tire size. His motor will spin at a higher rpm than your truck at the same speeds.
correct, but off a stop he has an advantage out of the hole sort of speaking. His motor will rev quicker. I've got too much time to think now as I'm on my ass on vacation :)
 

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Check the glove box RPO codes...GT4/GT5? check the G series codes of both and report ur findings. A work truck might have 3.42s. A smaller tire 342 truck might have a better final ratio than a 373 truck with taller tires. Cab configuration comes into play as well...years of trucks too
 

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correct, but off a stop he has an advantage out of the hole sort of speaking. His motor will rev quicker. I've got too much time to think now as I'm on my ass on vacation :)
His motor will have a greater mechanical advantage with the smaller tires. It's just like using a cheater pipe to bust a nut loose. With more leverage you can exert more force.
 

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His motor will have a greater mechanical advantage with the smaller tires. It's just like using a cheater pipe to bust a nut loose. With more leverage you can exert more force.
yes but then again run out of steam quicker on the top side :idiot:
 

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Discussion Starter · #7 ·
Check the glove box RPO codes...GT4/GT5? check the G series codes of both and report ur findings. A work truck might have 3.42s. A smaller tire 342 truck might have a better final ratio than a 373 truck with taller tires. Cab configuration comes into play as well...years of trucks too
both GT4
 
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