P tires to LT tires on an 07 ford expedition el?

[Rancher Ed]

Fit wise, as long as they are the same size or close you will be fine. One thing to check though is the max pressure the rims are rated for. I don't know if this is a problem, but as you get to a little bigger tire there are a few sizes that some have a max of 80psi and others in the same size just a higher load range have a max of 120psi, and some rims are only rated to 80psi so you have to check if the want the higher rated tires.

I think you are being smart switching to the LT tires, given the size of your rig (almost the same size as a suburban), especially if you ever tow anything with it. Even just loading it with everyone's stuff for a road trip, you could be close to the rating on the P tires.

Ed

 

[HHR]

It would be a good idea to change over to metal valve stems when going to an LT tire. Rubber stems are only rated to around 50 psi.

 

[murphy1244]

No problem. The letter designation signifies the load rating more than anything else. P tires are "passenger" with a 4 or 6 ply rating. LT tires (light truck) are 6, 8 or 10 ply rated.
Stiffer sidewalls, more capacity, but possibly harsher ride. P rated tires are used to give a better ride on a truck. LT tires have a higher min. and max. inflation rate. If a nice ride is important, you may lose some of it. It's not wise to run LT tires at the lower inflation weights of P tires. I did have a customer than put P tires on his 3/4 ton truck because they were cheaper. His low tire pressure light now stays on all the time. He can't safely inflate the P tires to enough pressure to put the light out. If you use LT tires you shouldn't have the tire pressure light problem. But you run the risk of having underinflated LT tires without knowing it.

The tire company should never change the rated tire on a truck,you could kill someone doing that.

 

[thatguy]

here is what I found on TireRack.com regarding the use of P tires on heavier trucks/suvs - it looks like you loose ~10% of the P tires rated capacity when used this way

You certainly dont want to cut any safety corners by going with a P tire.. If you go to tirerack and put in your tire size it will list both P and LT tires - then in the specs it lists the weight capacity and speed ratings..


Tire Tech Information - Load Reduction of Euro- and P-Metric Tires on Light Trucks

Brian

My bad in reversing that.. sorry

 

[zlock24]

Fit wise, as long as they are the same size or close you will be fine. One thing to check though is the max pressure the rims are rated for. I don't know if this is a problem, but as you get to a little bigger tire there are a few sizes that some have a max of 80psi and others in the same size just a higher load range have a max of 120psi, and some rims are only rated to 80psi so you have to check if the want the higher rated tires.

I think you are being smart switching to the LT tires, given the size of your rig (almost the same size as a suburban), especially if you ever tow anything with it. Even just loading it with everyone's stuff for a road trip, you could be close to the rating on the P tires.

Ed

We use this expedition to tow our 18ft carhauler and it's almost time for a new set of tires and I want to use LT tires since it weights as much as an f-250. I don't understand why ford doesn't use LT tires right out of the factory since the expedition weights around 7000 pounds. It's the long wheelbase model

 

[gengine]

You won't hurt anything going to a lt tire. I don't think you want to go to an e rated tire, but maybe a max of a d. As far as the rims, if it's a 17" rim, a 17" tire will fit. The higher rating (e) the more air, and the stiffer ride. An E rated runs at 80psi, a D rated is around 65psi, and a C rated is around 35psi IIRC. It all depends on the makeup of the tire. Going to a heavier tire doesn't hurt anything, going to a lighter tire can be dangerous if you overload it. The only downside I see is possible having an annoying light on the cluster.

 

[jeffsw6]

People buy Expeditions for a lot of things. Some tow, some just haul their groceries. The lady hauling her groceries around town does not benefit from the LT tires and they do not ride as smoothly as P ones. Also cost of course.

 

[Diamondpilot]

We use this expedition to tow our 18ft carhauler and it's almost time for a new set of tires and I want to use LT tires since it weights as much as an f-250. I don't understand why ford doesn't use LT tires right out of the factory since the expedition weights around 7000 pounds. It's the long wheelbase model

Ride, plain and simple. P tires ride better and it comes down to the test drive. The are competing with the Yukon and Suburban that do the same thing.

Chris

 

[Jimbrown]

I change out all my P rated tires for LT load range E almost as soon as I get them. Cars and 1/2 ton trucks. I actually like the ride on the LT's better than the P's. You do not need to run the LT;s at their full rating. I usually air them up to the load range D pressure.

I change them out mostly because I have to drive 13 miles of dirt to get to town and P rated tires just will not take the rocks and usually wind up cut and unrepairable in less than 3000 miles. It's just easier and less painful (changing flats) to change them out early.

 

[qstott]

The tire company should never change the rated tire on a truck,you could kill someone doing that.

I agree. And having said that, we had him sign a waiver and placed it in his vehicle file. I tried my best to talk him out of the P series tires for a least 1/2 an hour. His explaination was that he never carried any weight in his vehicle. He used it like a car. Even over my objections about liabilty if he loaned it to some one unsuspecting., he (in so many words) said, it's my money and I'll buy them some where else if you don't sell them to me. "The customer is always right" is not always true.