I recently purchased a 18.9 ft travel trailer that I tow with my 1999 Ford F-150 5.4 Triton P/U. I was running P275/70R/17 tires on my pickup. It was time to replace them so I decided to switch from P-rated tires to LT-rated tires. I decided on Goodyear Silent Armor LT265/70R/17E's they call for a max pressure of 80 psi. Am I ok with this tire on my F-150?
I am a bit puzzled over this whole tire issue because I have been told that I should stick to the size of tire and air pressure posted on the certification sticker on the door jam. My door sticker recommends P265/60/17SL tires at 26 psi front and 28 psi rear. I have seen door stickers on some F-150's that recommend a different type tire such as an LT-C. Why are different sizes and tire types recommended for the same model pickup truck? Is it because of the type of wheels on the truck rather than the vehicle itself?
I doubt your '99 F150 wheels are rated for 80 psi load range E tires. Their overkill for your load. For just a 19' TT your P tires will work fine unless you want to upgrade to a LT.
I would recommend load range C LT tire at 50 psi which will fit in with your F150 stock wheels.
The biggest down side to a E (10 ply rated at 80 psi) tire in your situation is their a heavy tire (45-55 lbs). They certainly won't need 80 psi for your load. So you air them down to your load requirement which will be in the 50 psi range. They will run hotter than need. With only 50 psi the tire will/can exhibit carcass roll. Carcas roll is simular to a half flat tire which may create handling problems.
I think you answered your own question on different tires and wheels on a particular truck.
As far as following the door tag psi recomendation, Ive found those pressures make a good starting point but its best to follow the tire makes recommendation for psi for the max load on the tires.
The 26-28 sounds about right for a P tire on a truck thats not carrying a load.
"good judgment comes from experience, and a lot of that comes from bad judgment" Will Rogers
'03 2500 QC Dodge/Cummins HO 3.73 6 speed manual Jacobs Westach Linex
'97 Park Avanue 28' 5er with two slides 16" BFG Commercial LTs
I believe jimnlin is correct. You really don't need to go over board on heavy duty tires. After all. All they have to carry is the payload of the truck. They do not have to carry there weight of the trailer.
If you get a tire rated for the GVWR of the truck. Say 2200lb each. Good to go. after all. You will never load the truck to 8800lbs.
He is also correct. That the lower psi is for a unloaded vehicle. When loaded. You will need to up the pressure. Notice on the side of the tire. (Example) It will say 2200lbs at 40psi. Meaning it only rated to 2200lb when it has 40psi in it. Not when it has 26psi in it.
My 2001 door sticker says LT265/70R17-C as the OEM tire. My understanding is this upgrade is part of the Off Road 4WD option. Sticker says 36 psi front and rear as the recommended pressure. This should easily cover your GAWRs.
I suggest you do not go over 50 psi unless you verify the wheel pressure rating. And besides 50psi or more will probably cause uneven tread wear and is unnecessary for the F150 capabilities.
If you get a tire rated for the GVWR of the truck. Say 2200lb each. Good to go. after all. You will never load the truck to 8800lbs.
Not necessarily. When I am loaded for our three month trip to Florida each winter and my trailer is hooked up I am over my 8800lb GVWR by roughly 150lbs.
Barney
If you get a tire rated for the GVWR of the truck. Say 2200lb each. Good to go. after all. You will never load the truck to 8800lbs.
Not necessarily. When I am loaded for our three month trip to Florida each winter and my trailer is hooked up I am over my 8800lb GVWR by roughly 150lbs.
Barney
But Barney. You got a 250. He/we have 150s. Even if we go over our rating by 1500lbs. We still won't weigh 8800lbs. Mine would only weigh 8550lbs. So I would still have 250lbs to go.
You aren't saying you overload your truck:
BTW. My tires are overkill for my 150. 2601lbs each. 10404lbs. Would make my truck drag.+
And looking again. You are right. I should have said more than the GVWR of thew truck. Obviously 2200lb tires are more than the GVWR of a 150.
* This post was
edited 07/04/09 08:17am by Terryallan *
A guys gotta do what he's gotta do!
Actually, last year we traveled a bit lighter. Our truck GVW was only 8760lbs. We are under our GCWR by 3720lbs though!
Barney
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