Regearing with stock tires

[teMoony]

Hey there,

My Tahoe is re geared to 4.1 but i still have stock tire size and no lift. Anything i should be aware of ? Any harm in that setup ?

 

[Gzes]

Gas milage will be different and you might be running different rpm and may strip out the gears. Id get the tires first then the gear imo

 

[bowtiefreak]

your fine, rpms will run a little high, but will give more acceleration.

 

[SunlitComet]

like bow said, quicker of the line acceleration speedo and shift points will be off if axle ratio is not programmed in the pcm. mileage will be a bit lower then usual.

 

[Donnie Yukonie]

like bow said, quicker of the line acceleration speedo and shift points will be off if axle ratio is not programmed in the pcm. mileage will be a bit lower then usual.

i didnt know you had to flash the pcm when you get new gears?

 

[SunlitComet]

yep. gotta do it. tire diameter size change too.

 

[bowtiefreak]

Yes sir. ABS gets a little crazy to as it thinks the rear tires are spinning at different speeds from the front. Throws off shifting too.

In my opinion, 4.10 on a 31-33" tires is perfect. Again, my opinion.

 

[_Dylan_]

i didnt know you had to flash the pcm when you get new gears?

Its because he is using stock sized tires with a different gear ratio. If he had 33s then he wouldn't have to.

 

[retorq]

He doesn't say what year truck he has, pre 95 I believe there was still the VSS box that have jumpers that can be manipulated to read correctly. 3.90s with my 30x9.5 tires reads just about dead on.