Sorry if this is not posted in the right place but I have a 2020 FX4 with a 2 inch level and 20 inch rims from the dealer and I'm thinking of putting on 17 inch rims and tires for the winter I'm just wondering can I just do a quick swap and be done with it and be on my merry way or is there anything else I should be aware of? I'm going to assume that they are stock brakes and calipers on the truck as well . Thanks for feed back.

 

Do it to it. No big deal. The only thing you'll notice is the speedo/odo being off.

 

And a constantly glowing tpms warning unless tmps is turned off via Forscan or you put tpms sensors in the winter wheels. Transmission shift issues, ABS issues etc. The pcm needs to know the correct over all diameter if it's different.

So to cliff note what I said, make sure over all tire diameter is the same and put tpms sensors on the 2nd set. Then all you have to do is swap them out at will with no issues at all.

 

Thanks I was thinking the same thing.

 

Thanks for the response Iwil keep it in mind.

 

Only if overall different diameter

 

Well here's my dilemma....right now what's on the truck is LT305/55 20 and I was thinking about 275/65 18....the website in want to order from list the 18 with that tire size but now I'm not so sure if it's as simple as take the 20 off and slap 18 on without something being screwed up?.

 

Use this calculator to discover closest overall diameter of different size tires/wheels. So long as you can stay within ¼" or less you'll be fine. Anything more and it's very possible things start breaking or wearing out prematurely.

 

It can be as simple as taking the 20 off and slapping the 18 on... If the ratio math works out to the same diameter.

Based on math alone, a 305/55r20 tire has a 33.2" diameter. The 275/65r18 has a 32" diameter. So mathematically, it's not as simple as just swapping the 20 for the 18. Your speed and RPM will read incorrectly for the 275/65r18. But a 275/70r18 or 295/65r18 are both the exact same diameter as the 305/55r20, if speedometer accuracy is an issue for you.

Alternatively, I'd just buy a speedometer calibrator or get set up with Forscan and just change the tire size when you swap tires for the season(s). Then you can just buy what you need/want without having to worry too much.

 

Thank you so much!!!! You just saved me from making a big mistake...