I have a 2007, f150 4door xlt. Stock tires are 255x70x17. I came across, for free and minimal use, 33 12.5 r17 tires. With no modifications, lifts, levels, etc. Would these fit without issue on stock rims? I know nothing about things like this, so please be kind. Just trying to save money on new tires right now.

 

Your original tires are 31 inches in diameter and 10.0 inches wide... Your new tires are 33 inches in diameter and 12.5 inches wide. They will FIT on the original rims, but may have some slight interference when turning the wheels to full stop. Also the new tires are 2 inches larger in diameter.. 2/31 is 6% so when you are really traveling 100 MPH , the speedo will read 94 mph... and at 70 mph, you will be reading 66 mph.

 

Your stockers are a hair over 31s, 10.2" section width. You probably have 7.5" wheels.

How much space is there between your existing tires and chassis and body components? Check the fronts at full lock both ways.

If you still have a couple inches, after adding the 1.25" extra on each side of the tire, you could run them. However, the 7.5 rim is too narrow, so you will have a pinched look, and possible poor wear and handling. And if saving money is an issue, you wouldn't want to buy wheels.

In addition, you will have an incorrect speedo, and your truck will feel like you have 1000lbs in the bed.

IMO, pass. "Free" isn't always the best way.

 

Might have to rethink this..

 

Do you have a leveling kit on your truck? If you have at least a 2" leveling kit they should fit without issue. But you still may want to get a rim with a slight offset to push them away form the frame and wheel well to avoid any rubbing. Or you can just put a space on your rims. Leveling kits are like $50, and spacers are about the same.

 

To the best of my recollection, yes. Yes, you can do it. Will it be good? No.

On your truck, a 6" lift kit spec is 315/70R17 Wheel Size – 17×8 w/ 5in BS

What I recall is that with that generation of F-150, you can run 33" ties on 2WD with a coil spring spacer, or 4WD no coil spring spacer needed.

It is definitely not ideal. It is not an "upgrade" in any way. You will gain an extra 1" in ground clearance. Bigger tires will put more rubber onto the road if traction is your concern. Only advantage is that you like the way your truck looks with bigger tires. It is not enough of a difference that it will "tear up" your transmission.

As I recall, I had 305/70R17 tires on my OEM steel wheels without any issues. I have 2WD. I also had a leveling kit installed.......which is a coil spring spacer.

Don't say "NO" just yet. You could still use these tires.

If you really need new tires, and these are free, then free is your best option. If you have the luxury of not needing tires, you can afford to buy the right tires in OEM size, then you might reconsider. Are these 33" tires rated for M+S, and you can mount them onto a spare set of wheels for winter?