Tire size help!!!

[NorthernExMax]

2011 limited max 4wd, i have a sticky situation. Door sticker shows 275/55r20, google says 275/65r18, 275/55r20, and 265/70r17? Heres the kicker- i have 275/75r18s all around, including the spare. DOT date on spare tire is 4210, so middle of october 2010 manufacturing date? Possibly original size with the truck? Regardless, i dont have the pocket for new rims and tires but i need tires so i went ahead and ordered the OEM 18” wheel tire size. I guess before i get them mounted tomorrow i should see if anyone else has ran into this problem? TIA

 

[ZigZagFred]

The door sticker data is your best source for tire size data. Discount Tire has an online tire selection tool.

 

[BigOleFordFan]

AFAIK, 20's are the OEM size for most 3rd gens, with a limited number coming with the 18's....and the 275/55/20 on that door sticker IS the most common, that's what came on my '011 too, so I'm stickin with them until I need tires again (just got new ones in Dec 24), at which time I plan to buy new rims and move to 285/65/18's, cause I want a little more sidewall height and a little more width too, without having to do any other mods to the suspension....

And I would strongly suggest you check that spare for dry rot & road worthiness (if that dated code is correct, it's almost 15 yrs old), and replace it along with the other 4 tires....the rim is probably a standard all steel one, and may be fine other than needing a good pressure washing before mounting a new tire on it.

Good luck either way !

 

[Gary Waugh]

As stated the 65 side Wall is the standard size, if your tyres don’t foul on the bodywork, then you are fine, just be aware that your speedometer will read too slow you will be doing 80 and it will show 70 or 75mph unless you fit a speedo healer, so keep an eye out for the boys in blue!! your car will also accelerate a bit slower but will have slightly lower RPM when cruising compared to the stock size tyres.

 

[NorthernExMax]

Not really sure if mileage would go up or down with the bigger tire, but I am trying to restore/improve the original power and efficiency, so with the 275/65r18s i put on i may see a little better mileage if i can keep off the throttle. Will go for a drive tomorrow and see how the ride is, but its a nice looking rig!

 

[Gary Waugh]

Regarding mileage, your expy will
Under read mileage, it will show less mileage than you have actually driven.

 

[BigOleFordFan]

As stated the 55 side Wall is the standard size, if your tyres don’t foul on the bodywork, then you are fine, just be aware that your speedometer will read too slow you will be doing 80 and it will show 70 or 75mph unless you fit a speedo healer, so keep an eye out for the boys in blue!! your car will also accelerate a bit slower but will have slightly lower RPM when cruising compared to the stock size tyres.

Not really sure if mileage would go up or down with the bigger tire, but I am trying to restore/improve the original power and efficiency, so with the 275/65r18s i put on i may see a little better mileage if i can keep off the throttle. Will go for a drive tomorrow and see how the ride is, but its a nice looking rig!

Regarding mileage, your expy will
Under read mileage, it will show less mileage than you have actually driven.

Lookie here for some more info on the above concerns:

Tire Size Calculator

The best tire size calculator. Use our tire size calculator to find tire size specs and suggested tire sizes. Then check prices for all available tire sizes.

tiresize.com

 

[Moeman]

I don't follow the what you're agonizing over - your door sticker said your vehicle came with 20" wheels and now you have 18" wheels installed? is it just the 75 vs 65 aspect ratio? That's a pretty small difference, hardly will be noticeable. Typically I find the smaller tire sizes give better gas mileage, vehicle will be a little peppier. But maybe you like the look of a taller sidewall. Maybe you'll find a better deal on one size or the other. I wouldn't sweat it too much.

 

[NorthernExMax]

I don't follow the what you're agonizing over - your door sticker said your vehicle came with 20" wheels and now you have 18" wheels installed? is it just the 75 vs 65 aspect ratio? That's a pretty small difference, hardly will be noticeable. Typically I find the smaller tire sizes give better gas mileage, vehicle will be a little peppier. But maybe you like the look of a taller sidewall. Maybe you'll find a better deal on one size or the other. I wouldn't sweat it too much.

The vehicle has 18” ford rims, possibly OEM. The door sticker calls for the 20” rim size on it, so idk guess im stuck with the 18s but i do like the size difference of rim to sidewall, and the downsized version i got rides alot better and can break the tires loose. Probably not gonna fork out money for rims unless one of these cracks, but even though i am not sure. We will see what i end up with though, but i believe fuel mileage will go up. Someone pointed out the gearing difference with tire size here, which honestly might come to bite me back for fuel mileage but im not sure

 

[lslick23]

If you go with the 275/65r18 they will be the same size as 275/55r20. This is a great site to compare tire sizes https://tiresize.com/comparison/