Anyone running 265/65/18's?

[iaonbb]

Wondering how big I can go without lifting. I know a 265/60 fits but still wanting something a little bigger. There's a lot of space to fill in there IMO.

Thanks!

[peterk9]

Originally Posted by iaonbb

Wondering how big I can go without lifting. I know a 265/60 fits but still wanting something a little bigger. There's a lot of space to fill in there IMO.

Thanks!

Welcome to the Forum iaonbb.
I assume your OEM tires are 245/60R18.
When changing tire sizes you want to stay within the recommended 3% diameter difference. A 265/65/18 has a difference of 6.31%, more than double what is recommended. Even the 265/60R/18 is over at 3.09%.
You can use the calculator at the following site to check.
http://www.1010tires.com/tiresizecal...?action=submit

Peter

[01STrunner]

But that can be alleviated through a module reprogram. Ford can do that for $100

[peterk9]

Originally Posted by 01STrunner

But that can be alleviated through a module reprogram. Ford can do that for $100

The main concern about going over the limit appears to involve the ability of the brakes to handle it.
The warning that comes up says that exceeding the recommended limit could risk brake failure.

Peter

[iaonbb]

Originally Posted by peterk9

Welcome to the Forum iaonbb.
I assume your OEM tires are 245/60R18.
When changing tire sizes you want to stay within the recommended 3% diameter difference. A 265/65/18 has a difference of 6.31%, more than double what is recommended. Even the 265/60R/18 is over at 3.09%.
You can use the calculator at the following site to check.
http://www.1010tires.com/tiresizecal...?action=submit

Peter

Yeah I have been checking out the 1010tires calculator. Great tool. I'm not too worried about the speedo being off or the brakes being able to handle it. Just looking for a beefier look. I've had several 4x4's in the past with larger wheel/tire combos and never had any problems. I LOVE the Explorer EXCEPT for the sunken wheels. Just doesn't look right being so wide on top and so narrow underneath. Most likely going with the 265/60's but just wondered if anyone has done the 265/65's with no lift.

Appreciate the responses!

[mech]

Diameter plays a factor on the increased load on the brakes, but you also have to consider the weight of the tire. Im not sure what tire you are thinking, but A BFG LT tire is gonna be a lot heavier than an equivilant sized all season radial. That extra rotating weight is harder to stop.

Overall though i wouldnt be too worried. Id love to see pictures if you do it.

[01STrunner]

I can attest to the heavier tires being harder to stop, mine are about 15% larger since i went from stock 31s to 35s. But if you just keep that in mind and increase your following distance to offset the extra braking time, the size increase works. It would really set your ex apart from a lot of the new ones.

[peterk9]

Originally Posted by 01STrunner

I can attest to the heavier tires being harder to stop, mine are about 15% larger since i went from stock 31s to 35s. But if you just keep that in mind and increase your following distance to offset the extra braking time, the size increase works. It would really set your ex apart from a lot of the new ones.

I agree with the last part, but, I would take safety over looks any day.

[01STrunner]

How big are the brakes on the 5th gen? I can think of lots of guys running 11" discs with 33s as their DDs. I have had to do a couple quick stops since I put bigger tires on and my 12" front discs and drum rears hailed it down to a stop at a good speed. However After being with the fire department most of my life I can understand any concern for safety.

[VinceL]

Originally Posted by peterk9

I agree with the last part, but, I would take safety over looks any day.

Now you just sound like an old fart, Peter!

[peterk9]

Originally Posted by VinceL

Now you just sound like an old fart, Peter!

Yup, you got that right Vince. I'm an official old fart. I've gone through all the other stages of life.
It's all downhill from here! Watching all the store flyers now for Senior's Days.

Peter

[iaonbb]

Very helpful thoughts. I have no problem being extra cautious as I find myself falling intothe old fart category a little more each day!

BTW, I'll be going with the P-metric Revo.

[corkey]

weight is not the only factor gentleman,,

sure a heavier tire will exceed the brakes,

BUT,,

i bigger tire tire will also be further from the center to outside edge thus having more mechanical advantage like a longer lever turning the brake rotor, and overpowering the brakes as well, the combination of the weight and the bigger lever could make trouble pretty fast,,

[mech]

Originally Posted by corkey

weight is not the only factor gentleman,,

sure a heavier tire will exceed the brakes,

BUT,,

i bigger tire tire will also be further from the center to outside edge thus having more mechanical advantage like a longer lever turning the brake rotor, and overpowering the brakes as well, the combination of the weight and the bigger lever could make trouble pretty fast,,

Corky,

Could you please explain your assertion? If you are referring to the additional distance between the axle and the outer circumference of the tire, that has already been discussed. The 3-6% diameter increase that was previously mentioned has covered your concern. If you are referring you additional width creating additional lateral distance from the rotor, then you are incorrect. The additional distance laterally from the rotor is largely insignificant with regards to braking load.

[01STrunner]

He's referring to our talk about the extra weight of larger tires. We ignored the fact that the radius of the weight is also increased and because torque is a force tangential to a circle you must not only think about the added weight but the fact that the rolling weight has added extra torque due to the larger radius.

[01STrunner]

I think the brakes would be fine with that size tire. It's not even a 32. Plus the wider patch on the road will offset some loss in stopping distance.

[mech]

Originally Posted by 01STrunner

He's referring to our talk about the extra weight of larger tires. We ignored the fact that the radius of the weight is also increased and because torque is a force tangential to a circle you must not only think about the added weight but the fact that the rolling weight has added extra torque due to the larger radius.

Gotcha. I made the mistake of assuming that if additional radius is stated as creating additional load, and additional weight is stated as creating additional load, then it would be self evident to all readers that the combination would also create additional load.

I guess corky wanted to make sure we gentlemen understood that.

I still want to see some photos.

[corkey]

yes Sir,
i looked at this in a strictly engineering point of view, i do also know that tolerance factors are built into most systems, like a possible overage in the addition of bigger tires or heavier tires,,
like a stock brake system will have say a 35 % tolerance to account for weight inside the vehicle with say 4 or 5 people, which adds to the weight of the vehicle loaded, as opposed to with just a driver,, so there is a maximum weight allowed,, which is posted on the door sticker,,

using a heavier tire will decrease allowable interior weight , so yes, you should be safe if you run the bigger heavier tire, but keep the weight inside the Explorer down to say the driver and 1 passenger,,until you also hook up a trailer,,

there are alot of variables in designing a vehicle to take into account, as well as the customer factor, and the possible overloading of the vehicle,,

looking at the variables as you did is commendable , as not most people would,,
hats off to you Sir,,