can you run 70R tires on the front axle and 75R tires on the rear axle of a '03 4X4 Chev 3/4T PU?

Answer 1

NO! What you propose is quite dangerous.

A 3/4 ton truck is going to have C or E load range tires which you will only find in a 75 series aspect ratio. In a 70 series aspect ratio pretty much all you will find are standard load P-metric tires which lack both the load carrying and inflation capacity required for this vehicle.

Stick with the size, load range and inflation pressure recommended by the vehicle manufacturer the information for which is found on the Vehicle Information Tag inside the drivers door frame.

EDIT

I forgot to add, since your truck is 4WD if you run different sizes front and rear you will fry the transfer case.

Good luck.

Answer 2

If I were you run a tape measure around both sizes of inflated tires on the rims you'll be using and the tire stagger is zero, go for it.

On any four wheel drive vehicle all wheel and tire circumfrences must be the same. If not as soon as you engage your four wheel drive the front and real wheel speed will be different. You'll eat the tires alive. It 'll also beat your front and front ring and pinion gears bearings, transfer case, axles, driveshafts, and transmission to an absolute early death.

Answer 3

No You cant do this as the front axle will be fighting the rear axle due to the difference in circumference of the tires

Answer 4

You did not provide the full specification of the two tires, but the answer is Yes, IF AND I DO MEAN "IF" the outside diameter is the same or VERY close.
Do not do this if the OD is different!!!!

Answer 5

you can, but the odometer is going to be off, and it will change your gas mileage.