How much air should I have in the tires when towing? (2004 F150 5.4 engine and tow package...towing a 3300 lb 2 horse aluminum skin trailer...total weight with animal and tack and me...around 5000 lbs)

The tires say 35, and obviously that is for everyday driving. Also, should the front tires have a different amount in them than the rear tires while towing?

I have "P" tires on the truck that came with the truck...why does Ford do that? Why don't they put "LT" tires on their trucks? Doesn't that make a difference too? Right now, I can't afford to change the tires.

I notice that the RPMs are around 2-is that good? Like I have said in previous threads...the truck feesl a little sluggish when towing.

 

I agree, Ford should put LT tires on all their trucks, but the P tires ride softer, which helps sell trucks. You should look into a set of LT's when these ones wear out. The LT's have stiffer sidewalls and less tendency to 'squirm' when under a side-load (when cornering) while carrying weight.

Whenever your tires are loaded, you should fill them max or near-max pressure, especially the rears, since that's where the trailer tongue weight is being carried. Underinflation causes heat, which is a big cause of tire failure, as well as overloading. A combination of overloading and underinflating is a blow-out waiting to happen.

Engine rpms are controlled by 3 things, other than vehicle speed: axle ratio, tire diameter, and what gear the tranny is in. If the truck feels sluggish in high gear, take the tranny out of overdrive and tow with it in 3rd gear instead. You can also shift the tranny manually when taking off from a stop so you can hold it in the lower gears longer and let the engine wind out a bit more before shifting up, that way the motor doesn't bog out as much after the upshift. There is no danger in shifting the automatic tranny manually, just dont forget to shift it and redline the motor...

 

check the Goodyear and Michlen web sites for recommended tire pressures for the load being carried per the tire and rim size,, they have a good pfd download you can keep for future reference,,

on the new F350 SRW CC LB,dealer had 80 in all four of them,, run with 65 in the front empty and towing,, run with 60 in the back empty and move up to 73 when we hook on the 5th wheel,, we are in the 20,000 lb range down the road according to the J Scales,, do have E rated LT tires on the truck and 5th wheel,,
enjoy,,

 

Use the max number on the tires, or the max on the door. Nothing more is needed. Don't use less though, its asking for issues.

As far as RPM's go, 2k sounds low, are you towing with OD off? Be sure to turn it off. My 5.4L runs around 2500 at highway speed, 3000 at 70 (but my truck is slightly less arodynamic than most)

 

I do tow with the overdrive off and the RPM is usually 2000-sometimes 2500 but never over that.