Driving with Three General 265/65R17 and One BFGoodrich 265/70R16 Tires

Am I doing any damage to my truck doing this? Looks like the net difference is small.
Any feedback much appreciated. Thanks!

 

Put the mismatched one on the front. Then buy the right tire/wheel.

 

^this guy is right you know.

 

Thanks for the replies. Why not leave it like this? Any serious issues you gents can think of?

I was looking here and found the difference to be minimal:

https://www.tacomaworld.com/tirecalc?tires=265-65r17-265-70r16

 

Except the tire's actual dimensions can vary greatly based on tread design and numerous other factors.

 

And preferably don't operate it in 4 wheel drive....though low speeds and reduced traction shouldn't hurt it