Thread: 17" rims to 18" rims

Will I have any issues putting 18" rims on my 09 f150. I have 17" on now

Absolutely not as long as the bolt patterns are the same.

Originally Posted by RhinoZ24

Absolutely not as long as the bolt patterns are the same.

Will it change my speedometer

No, the speedometer is measuring how fast your driveshaft is spinning, not your wheels. The only thing it will change is the torque just a bit, and it will be easier to get up to speed because your wheels have to spin less to go the same speed as compared with the 17", they have to rotate more times to go the same speed. But your speedometer will remain the same and it will still be accurate as its the speed of the driveshaft. So you will have no problems. I did the same thing to my 05, went from 17" to 18", been like that for about 8 months and it works fine and my speedometer is correct, just so you have some reassurance.

Originally Posted by RhinoZ24

No, the speedometer is measuring how fast your driveshaft is spinning, not your wheels. The only thing it will change is the torque just a bit, and it will be easier to get up to speed because your wheels have to spin less to go the same speed as compared with the 17", they have to rotate more times to go the same speed. But your speedometer will remain the same and it will still be accurate as its the speed of the driveshaft. So you will have no problems. I did the same thing to my 05, went from 17" to 18", been like that for about 8 months and it works fine and my speedometer is correct, just so you have some reassurance.

Thanks for the info!

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Originally Posted by Raptor05121

Actually your vehicle speed comes from the VSS (appropriately called the vehicle speed sensor) located on the rear diff. Going from 17 to 18 WILL change your speedo reading IF you maintain the same tire size (IE: 17" with 265/55s going to 18" with 265/55s will cause the VSS to read slower). By how much slower is another question. Since the rim is 1" bigger, the overall height of the tire/rim combo is only going up by .5" in each direction, so at 60mph indicated, you might be doing 58-59mph. However some trucks do read fast towards the 70mph limit. I went from P235/55 to P265/75 and my speedo reads about 3-4mph slow. At 65 indicated, I'm doing 69mph on the GPS.

tl;dr- Yes it will read slower but with an 1" gain, you won't tell a difference unless you were going really fast.

Thanks for the info!