Is it bad for your truck to go to a smaller size of rim besides your stock rim. I have a stock 17 inch rim and if I went to a 16 inch rim would it be bad for my truck and mess up the warranty at all. Basically how would it efffect my truck in all ways?

 

They put 16in rims on the same truck for years so, I wouldn't say it's 'bad' for your truck, just 'different'.

I don't know all the ways changing will 'affect' your truck, the CPU was programmed for 17" when it left the factory so, some things will be different.

One way it will different is it will feel like you added 12 to 18 horsepower to the motor.
Also,
the truck will be quicker off the line.
Slightly higher rpm at speed.
It was governed for top end at the factory and you shouldn't be driving that fast anyways.

If you use the same tires, the truck will sit a half inch lower.

 

I was kidding about using the same tires.
That whoop-whoop sound would be very annoying.

 

nothing will change at all, as long as you use the same tire hight, so if you had 31" tires with 17" wheels and you go to 31" tires with 16" wheels nothing will change at all, good luck

 

in someinstances the companies use larger rim diamaters to fit over the brakes. Not sure but you would want to make sure that the 16" rim will fit over the rotors.

 

On the New F150s you cant use anything smaller than a 17" wheel because of the rotors. On the 97-03 F150s you cant go smaller than a 16" wheel.