I have a 1995 F150 4X4. Ford requirement is P235/75R15. The person who owned it before me put LT 31.5?R15. It rides like a truck.that is ok. If I put the recommended sizxe back on will the tires wear faster because of the truck weight.?
I have considered putting 16 in rims on but I am not sure there are any made to fit this truck. as an after thought I don't think it would be an advantage to my gas mileage. thanks Fordtrucklover

 

I would say stay with the bigger tire. You will not get any better gas mileage out of the smaller tires and I don't think that wear would change either. I hear people say that they had lost MPG with bigger tires and that may be a little true due to the fact that you are changing the gear ratio but if you look at the sizes you are talking about there is very little difference IMO to even take that into consideration. I also think that a lot of poeple don't take the speedo into account. I whave gone bigger may times and never noticed a big drop in actual MPG. What is your bolt pattern by the way?

 

my wheels are 5 lugs; 5 1/2 inch centers. what about the wheel size?

 

I'm sure that almost every wheel maker makes 16 for your truck. I know that Eagle Alloys does and so does American Racing . I'm sure that all of them do. As for the size of tires for your truck I do not know but I am sure 265/75R16 would fit fine as a matter of fact I have a pair that I need to get rid of with stock rims off a '99 f-150. Click on the link in my signature and you can see the stockers on my truck.

 

Going to a smaller size will not have an effect on tire wear. You're only talking about 1" of height difference between what you have now and the 235/75/15s. Going to 16" wheels will do nothing but cost you money. You will gain NO increase in MPG or tire wear by going from a 15" to 16" wheel. What you'll find out is that after you buy new wheels the tires for 16" wheels are more expensive than tires for a 15" wheel. Tire selection is also better for 15s as well. The reason people don't run them on 97+ F150s is because they won't fit. Keep the 15s and the 31s.

 

actually the bigger tires should give you better gas mileage on the highway because your rpm's at a given speed will be lower with the bigger tires. but in city driveing it might hurt your milage as the engine has to work a little harder to turn those tires every time you stop. I think it would probably balance out to a no change in the mpg unless you do alot more of one type of driveing than the other. as far as wear goes I am not sure. logic tells me that on a bigger tire one revolution goes a longer distance therefore you will get more distance out of the same number of revolutions in a bigger tire. so for instance if a tire tread is good for say 10 million revolutions( just a guess) you shaould be able to go farther on the bigger tire in those number of revolutions compared to the smaller. maybe my logic is wrong but it seems to make sense to me.

 

A larger tire will not have more wear than other tires. They're rated the same as other tires of the same make. A 33/12.5 BFG AT is rated to last 50k and a 35/12.5 is also rated to last the same amount. Also big tires will NOT increase your MPG. It will lower the MPGs (though in the 2 sizes you're talking about you won't see any difference). What happens is the rpms are lower so the engine is taken out of its power band and thus has to work harder to turn the tires requiring more fuel. Also since the truck has to work harder to turn larger tires at highway speed if its an auto tranny then it will have to lock and unlock the torque converter or shift down into 3rd gear to be able to pull the truck along if theres a headwind or if its going up a grade. This will also hurt the MPGs. This is what I've gone through with my F150, but I went from a 30" tire to a 35" tire and have so far kept the stock gears. Going from a 235/75/15 to a 31/10.5/15 these effects will be unoticable. You're talking less than an inch height difference between the 2 (they are equivalent tires, just one is measured in mm and the other in inches).