Largest tires?

[fishhuntwork]

I have a stock 2009 F150 Xlt. I currently have 17" rims and I'm looking to upgrade the rim size. Whats the biggest rim I can run without having to change the suspension or having the tires rub. I seen on ford.com that the xlt package does give the options of 20", does anyone have 20's on there xlt?

[Powerstroke]

Are you asking about rims or tires?

Changing rim size will not give you any fitment problems unless you're looking at trying to run 26's or something. The only concern will be the backspacing on the rim. Any reputable dealer will know how to keep things as close to normal as possible.

You can easily run 20's on a stock truck. Make sure your tire/rim package will fit before purchasing. Its fairly easy to get a "stock size" tire on just about any rim size you want.

If you want larger tires also, you can fit up to a 33" tire in the factory location. You'll be looking at a 33x12.5" max or a 285x75. Of course if you go to 20's then the tire dimensions change slightly, but keeping a 33 in mind and you can find a tire. Any tire companies HSOforum should have a sheet that lists the actual size of the tire in inches so you can compare different tires with metric sizes.

[delcecchi]

What is the point in going to bigger rims and keeping same size overall? Just to look kool with narly rimz?

[Powerstroke]

People do lots of things to customize their vehicles, sportsmen especially.

[hanson]

What is the point in going to bigger rims and keeping same size overall? Just to look kool with narly rimz?

Well there is the cool factor but sidewall stiffness is another benefit. I don't think you gain any off road performance but you would a little on road.

[Macgyver55]

Well there is the cool factor but sidewall stiffness is another benefit. I don't think you gain any off road performance but you would a little on road.

The performance gain is often offset with reduced ride quality.

[fishhuntwork]

So would I be better off going with a 285/70/17 vs a 265/70/18? I'm looking to get a larger ride height. I know the 18" tires will cost more plus I will have to buy rims, is there really that much more height diff between the 2 sizes? Thanks for your help

[Macgyver55]

So would I be better off going with a 285/70/17 vs a 265/70/18? I'm looking to get a larger ride height. I know the 18" tires will cost more plus I will have to buy rims, is there really that much more height diff between the 2 sizes? Thanks for your help

These two tires are very very close to the same height, with the 17 actually being the taller by about one tenth of an inch.

The 17 is however just under an inch wider than the 18.

A wider tire will generally, (not always) give less traction in snow, and some reduction in mileage due to rolling resistance.

[BoxMN]

18" tires, for whatever reason are WAAAAY more spendy than 17" or even 20" I believe. Not sure, but my brothers 18" cost him a small fortune and his next born ...but I am not a tire guy, so not sure...

[skolfoppa]

285 v. 265 is the width of the tire. The second number(70 in your example) is the sidewall ratio(height). The more sidewall v. rim/wheel size usually gives you a smoother ride, as the tire absorbs the road. 18" tires are more expensive, and if you have a failure(blown out sidewall) in bf nowwhere, there is less chance of an available replacement on hand. Why not keep the 17s and throw on larger tires? Btw, there are tire/wheel size calculators if you search online that will show you the differences in height.Skol.

[Lund4ver]

I have a 2005 F150 with a 2" leveling kit in the front, and run a 275/70R18 on the stock wheels without problems. The tire is slightly over 33" tall, and about 11" wide roughly. It is the same width as stock size, just taller. In all I gained close to 4" in height in the front due to the leveling kit and taller tires. I really like the look for the truck now, compared to the "stock height". Down side like others have said is that 18" wheel tires are more spendy and most are a heavy load rating. The Hankook Dyna Pro ATM RF10 that I have on my truck are a load range E, so with a F150 I never have to worry about overloading the tire, just overloading the suspension.

Powerstroke (Hi Andy), knows his stuff with the trucks. If you have questions, don't hesitate to post them.

[Powerstroke]

fishhuntwork, it seems you are confusing rim size with tire size. Going from a 15" rim to a 17" rim to a 18" rim to a 20" rim, does nothing to increase ride height. That is simply the diameter of the rim the tire is mounted to. The most common reason to change rims is for cosmetic reasons. Sometimes new rims add strength, but that doesn't always mean bigger.

If you're looking for increased ride height, then you need a larger tire. You can fit a larger tire on your truck without changing rims. Like I said before I know a 33" tire will fit your truck just fine. A 33" tire can be mounted on any of the rim sizes I listed above. So if you want to keep your 17" rims, keep'm. It will allow you to spend a little more on a quality tire.

If you're looking for the 17" then you should look for tires in the size 285/70, 285/75 or 295/70 range. Those are the largest you can fit without rubbing. Otherwise you can keep the factory size of 265's. Another option that lund4ver mentioned is adding a lift, although they are expensive for your truck. You could always crank up the torsion bars a little to get more space in the wheel wells. Thats what I did to my '01 F150, which was the same body style as yours. Of course then I added a 3" body lift and 35" mud tires on 16x10" rims! Woo hoo!!

[Tator2k]

I have a Ford option for Stock 275/55/20" on a 2007 F150. If I remember correctly you can go to a 305 series tire on a 20" within any suspension mods. but does require a 9.0-9.5" wide rim. Factory rims are 8-8.5"

[Lund4ver]

Powerstroke - His truck is a 2009, so is has the coil front suspension, so he would only need a leveling kit in the front to raise it to clear the taller tires in the front, the rear will be fine as is from the factory, unless he does heavy towing, then an add a leaf would take care of that problem. I have the Autospring 2" leveling kit installed in mine, and got it off a HSOforum for under $100, and it is very well built.

Here is stock height with stock tires: Yes my son is a good measuring device!!

and here is a similar picture after the 2" leveling kit, and 33" tall tires:

Hope this helps out.

[Powerstroke]

Whoops, I misread the OP's truck. I guess I was reminiscing about my old truck. LOL.

I wouldn't worry too much about rim width since its a pretty heavy truck, however a 12.5 is the widest tire I would put on an 8" rim. I had 12.5" wide tires on a 7" rim on my last superduty and it worked just fine for 35K miles with no tire problems.

I don't know the new model F150's as well as older models, but it sounds like its similar to the old ones. Although it is possible to squeeze a 305 in the wheel wells, different tires are wider and have bigger sidewall lugs than others and may rub. If you're interested in 305's then you need to consider the individual tires to run.

[fishhuntwork]

I ordered a 2" autospring yesterday. So know I think I will go with a 33" tire maybe one size bigger. Thanks for all of your help!!

[Lund4ver]

After you install the Autospring leveling kit, don't forget to have an alignment at a shop that knows what they are doing.

[fishhuntwork]

Installed my autospring 2" level kit on friday, it was alot harder than I thought it would be. It would have been alot easier if I was using a hoist. I'm now trying to figure out if i should put the rear end blocks in or not? I tow a boat in the summer but I don't tow anything in the winter. I can't wait to get some new tires. Thanks for all your help and input!

[fishhuntwork]

I installed my rear 3" blocks yesterday on my f150, now it seems I have a vibration at slower speeds but not at highway speeds. Its a 4x4 so there already was a 1.5" block in the rear. I was wondering would it matter if you tighten the u bolts on the axle when the tires are off the ground or when there on the ground? There were alignment pins on the axle and the springs, so I can imagine why I would now have a vibration. I had a small vibration/ shutter when the transmission was shift into 3rd gear before.

[Macgyver55]

Changing the ride height with blocks will change the drive shaft angle.

Changing the drive shaft angle will often create a vibration, so it is important to keep both yokes as close to parallel as possible. If you have excessive angle it may be a vibration you cant get rid of without further mods.

The picture shows what to look for.

[fishhuntwork]

I understand driveshaft and pinion angle, I thought of that too. I figured adding a 1.5" will probably increase it a little but not enough to give it a vibration.

[Macgyver55]

That inch and a half can be a lot of angle depending on drive shaft length. Also, when drive shaft angles are determined on vehicles they tend to make the angle better as the vehicle is loaded and rarely leave much fudge factor for raising it. In addition, if you have a marginally bad u-joint that is still tight, forcing it to move further (sharper angle) than it used to, could also cause it to vibrate.

[Powerstroke]

I would lean more towards a bad ujoint than blaming the lift. An F150 is hardly a short wheelbase vehicle. Even a jeep with a 2" lift doesn't need a new driveshaft.

I would double check the blocks and ubolts since you could be feeling some axlewrap. Adding a larger block will increase the amount of torque placed on them and can contribute to the shuddering.