Tire Pressure LT Ds vs LT Es and Ride-Rite Questions

[BFL13]

Not sure this is the right forum, but if it belongs in Class C, please move it. Just got this used MH, checking it out.

The truck part is a 1991 Ford 7.5 gas 1-ton dually. The door specifies front and rear tires as LT215/85R16D at 58lbs.

It has LT215/85R16Es on it. So what should the correct tire pressure be on the Es to meet the door specs for Ds?

I know there are tables for LTs giving the psi for the weight on the tires, so it could be figured out. But if this is an easy question, without having to go there, please give me the right psi. Thanks.

The thing also has a set of Firestone Ride-Rite helper springs on the rear with the 224 Bellows. I can't figure out where to check their air or add/subtract air to them, but I will get to that later. (They are supposed to be 4 1/2 to 6 1/2 inches high, and look to be about that.) Meanwhile, the instructions say the vehicle should not be lifted by the frame.

How do you jack the truck/MH up to change a flat tire if you can't lift it by the frame? Also what about having it in the garage and they put it on a hoist? Is that lifting by the frame? It is going to a garage in a few days for a "mechanical inspection" to see what I have gone and done! Thanks.

[BFL13]

Grit dog wrote:
Think of a tire like a balloon. The air is holding up the vehicle not the tire. Without getting into semantics, the pressure needed to support a given load is the same regardless of tire load rating.

I was thinking maybe the sidewalls or plys would make it different somehow. 58lbs is more out of 65 than out of 80 lbs, so I was thinking ratio would make it more than 58 with the E, but I didn't know, so I asked.

The Es are all at 58 now based on advice here. Thanks again.

The garage says they are familiar with Ride-Rites, so I will get clued in on those when it goes in later this week.

[Grit_dog]

Think of a tire like a balloon. The air is holding up the vehicle not the tire. Without getting into semantics, the pressure needed to support a given load is the same regardless of tire load rating.

[BFL13]

Thanks, that makes it easy.

(Bonus for me is the back inner tires in the dually have extensions for their air valves, and you can get at the front set's valves easily, through a hole in the wheel even though the valves point inwards. --I don't need a special air chuck. Lucked out there I gather. I never had a dually before. )

Anybody know anything about the Ride-Rite question? Thanks. I don't even know if I even need them. If it is too much bother, I will take them off.

I think some previous owner towed a car, because it has a hitch receiver on the back that looks like it would do for that. Perhaps that is why it has the Ride-Rites--not a clue. It is a 28 footer and there is a long overhang at the back past the back wheels, so I imagine it can't take much weight at the bumper. ( If I need to get into that I will get on the Class C forum)

[mike-s]

BFL13 wrote:
The door specifies front and rear tires as LT215/85R16D at 58lbs.

It has LT215/85R16Es on it. So what should the correct tire pressure be on the Es to meet the door specs for Ds?

Absolutely no change. When going to a higher load range tire, the load/inflation tables simply get extended to cover the potential increase in capacity.