Biggest Tires on F150?

[N80]

I've got a 2003 F150 SuperCrew 4x4 with towing package. it is going to need new tires soon and i'm looking for something bigger.

But, before we start talking about Big Foot, etc, I do not want to modify the suspension at all. I could go for a 1-2" lift kit, but no one makes them. It currently has all-terrain (hah!) 265 70 R17s on it. I don't relate well to p-metric sizes. I'm used to 31x10.5" mud tires on 15" rims on small Japanese trucks with manual transmissions. (I got this current truck beause I need it, but I don't love it.) It is like a big lumbering yacht off road so I'll be beefing up the shocks as well as the larger (mud) tires.

So, can anyone tell me, off the top of their head, what the largest tire I can get on this truck without major mods. I suspect it won't be much taller or wider than what I already have, but I'll take what I can get. Looking at it, the main problem will probably be rubbing on the front while turning as there isn't much clearance between the rear edge of the front fender. Plenty of room for the back tires.

Thanks,

 

[Bird]

George, are you planning to change wheels, too? You can go to Discount Tire for that OEM size and click on "View optional/plus sizes" and if you don't understand everything about the "plus sizes", you can click on "What are "plus sizes"?" in the left column for an explanation. Maybe this will help?

 

[N80]

No, I'm planning on keeping the rims, they look okay and are 17" plus I'm past the days of caring what my truck looks like. Kinda sad. But, I'll check out discount tire. I've purchased tire and wheel packages (mounted) from other online sources and it often comes out cheaper than buying them at a tire store. But since I'm just buying tires, and have no way to mount them myself, I'll probably buy locally. But if Discount Tire can tell me the size that will sure help! Thanks.

 

[strokerduster]

about biggest that will fit stock rim is LT285 70 17 8 ply. they make a 305 that will fit the truck but is too big for the stock rim. discount tires reputation around here is "DISCOUNT THE MONEY OUT AND LOTS OF IT!". the LT is much heavier than p metric that came on it................

 

[MikePA]

Tirerack is also a good place for tires and wheels. They also have local installers they will ship the tires to. They do not indicate any other tire size without changing wheels. If you want to change wheels, you could go up to a 305/30-26". /forums/images/graemlins/grin.gif

 

[HGM]

I usually use 4WheelParts for refrence. It shows you should be able to fit up to a 32" tire wich is about a 305. I have seen some 150's with 305's and they looked good. One of the dealers I used to work with sold them new, so I doubt there were clearance issues, but they may have been Super cab's instead of Crew's.

You can also use Michelin's web site to find the size comparison. They list the tire size then the outside diameter.

Happy shopping, they aint cheap..... BTW, I'll submit my vote for BFG's in a 32"... /forums/images/graemlins/grin.gif

 

[RobertN]

Not sure about the size that will fit. But, you might want to be aware larger sizes will throw off you speedometer and computer. You will also have less acceleration, especially if you tow. Remember, taller tires raise your overall gear ration. For example, if you have 3.73 gearing, going up a couple tire sizes is like changing your gears to 3.50 ratio(not exact, but in the ballpark).

A couple tire sizes is not enough to bother with a $2500 gear change to compensate, but you should be aware of the overall affect on performance.

 

[HGM]

Good point on ratios. Though if you just go with what will fit, you'll be fine. The speedo can be recalibrated through the cluster. This will also help return shift points to normal.

 

[N80]

Yep, thanks for the tips. I used to be into 4 wheeling as a hobby so I'm fairly familiar with all the tire size issues. I'm talking about minimal changes here, probably no more than an inch. Hopefully can find something a little wider.

I've checked all the source cited so far, but not much info there. Discount tire only lists street tires for my rim size. The 17" rims might be the problem.

I'll probably have to sit down with a local dealer, but they are usually very hesitant to recommend anything but the OEM tire size.

 

[1bush2hog]

You may also want to check out what people recommend on other specific forums.

www.ford-trucks.com/forums

www.dieselplace.com/forum


Not knowing the width of your rims, they may be too narrow to safely accomodate a 305 tire. The following chart might help you.

http://www.sstire.com/tireheights.html