Tire rating on tow vehicle

I switched my F150 Ecoboost from P C rated tires to LT E tires and 60 psi front and 70 psi rear. Can't really tell any major difference in ride quality except for feeling more stable. Only towed my boat so far. Having to move my trailer axel back 3" to load the tongue more as it sways some and feels "twitchy". JMHO

Seriously? A 9000lb 5'er with a 1/2 ton. I tow the same weight 5'er with my 2500. My pin is 1800lbs, add my wife and I @280lbs and whatever else and were 200lbs over GVW but 1100lbs under the RAWR. Have you even checked your CC rating on the door sticker? Tires would be my 2nd issue. No way you're not over your trucks RAWR.

As far as the tires go just look on the sidewall at the Max Load at max PSI. As long as that is equal to or greater than the RAWR of the truck then they will be fine. It's the truck that's the problem though not the tires. Even P rated tires carry enough load for the trucks RAWR.

The truck will be fine with the LT C load range tires on a F150 that may have a 3800-4050 lb RAWR. You sure don't need a E tire in that case.

The problem we get into is E tires come on 3/4 ton HD trucks with 6000-6200 lb rear axles with wheels rated for that weight and 80 psi. Most 1/2 ton trucks wheels simply aren't rated for 80 psi.
It makes no sense to derate the E tire to a lower pressure to match the 1/2 ton wheels when the LT C tires will work fine.
I've had two different trucks with E tires. Didn't like the ride/handling especially carcass roll from using 50 psi (max wheel pressure) in them when carrying a load or towing a trailer.

Tires are happier at max pressures when carrying a load. You will use max pressures in your 50 psi C load range tires for many trouble free miles.

Now if your running a over load condition on the rear axle then its best to upgrade tires and wheels to the LT E.

todd66fan wrote:
I went from a f250 with an E rated tire to an f150 with a C rated tire. Should I have any worries pulling my fifth wheel, around 9000 pounds? (which also have E rated tires)

Well the fact that your F150 has C rated tires suggest that it isn't a Max/max with a 8,200# GVWR, which would also suggest that you only have a 4,000# rated rear axle. That 5er could easily have 1,800# pin weight.

Why with a 9,000# fiver would you step down to a F150 from a F250, if you haven't pulled your 5er with the TV, you may be in for an unpleasant surprise.

todd66fan wrote:
I went from a f250 with an E rated tire to an f150 with a C rated tire. Should I have any worries pulling my fifth wheel, around 9000 pounds? (which also have E rated tires)

Yes

Forget the tires and go by the GVWR. If the trailer tongue weight PLUS everything else being carried by the tires is under your trucks axle rating it should be safe because tires are required by LAW to be capable of handling the maximum weight the truck is rated for. Now that being said, stronger E rated tires will be more stable than the 6 ply tires (C rated) but are not totally necessary if the total weight is less than GVWR and/or axle rating. I'm actually surprised though that a 5th wheel would not overload a light duty F 150 and if it were a heavy duty model it would already have E rated (10 ply) tires. 9,000 lb. 5th wheel more than likely has over 2,000 lb. of pin weight and unless your truck is a heavy duty model it won't carry that much payload.