Tire size and over height issue?

changing tires won't fix this. there just is not 14 inches( you only gain half) between tall 24.5 and lp 22.5. you have another issue going on. either your suspension is set way to high, or the ride leveling valve isn't functioning properly. also you may have an exceptionally tall fifth wheel. it's not uncommon for a truck set up to pull a flatbed to have a tall fifth wheel so the winches don't tear up drive tires. measure your fifth wheel height. I think 36" is what you need to be able to stay under 13'6" with high capacity dry vans and refeers. Give a trailer dealer a call to double check the 36" number, it's just been to long since I've had to know that for me to trust my memory. it may be 38.

 

Stay west of the Mississippi and you are legal to 14 ft.

 

It looks like you need to lose 8 inches and won't do it with shorter tires and a low mount 5th wheel.

 

5th wheel height should be more in the order of 46"-47".

379,, you made sure that 14'2" wasn't a high hook? (can happen to the best of us) Sounds really excessive.
As spyder7723 said, double check your air-ride height setting (and other items he mentioned). Adjust it at low end of mfg spec, but within spec.

 

Height for 13'6" trailers is generally 47.5" max. Those trailers are 115" from plate to top of roof tops..so you gotta be at 48" or less to make that east coast legal.
i have a 3" riser under my fifth wheel. And the suspension lifted a touch, riding on 24.5lp. It's 50.5" top of the fifth wheel. So if I hook a trailer like you've got I'm right below you. I could change out the slider to one that doesn't have the rise, and lower my leveling valve...but then I'd have to take off my full fenders and chop off the ramps that are welded onto the back of my fenders to prevent winches from creaming them.
If you don't have full fenders, see about lowering your setting on your leveling valve. (Mine has 4 settings) also next set of rubber go lp24, sucks to wait for it and risk it all in the meantime but if you don't have the $ that's your option. I don't know if you have a high slider under your fifth, check it out-I looked at Fleetprides catalog a while back n the Fontaine I have I could get the one I have or a standard height one for about $1000. Options are out there..

 

Don't the scales have over-height sensors? Would they even let you leave being that high?

 

Its common to see trucks with ramps on the end of the tractor chassis for this same reason. Some drivers leave the jacks so high that when they drop them its hard to pick them up.

 

You want your 5th wheel height to be no more than 47". Measure from the top of your frame to the top of the 5th wheel, and I think that the lowest mount you can get is around 7". Other than that, it is suspension height setting or tire size. Be careful changing your suspension height as you can get your driveline angles wrong. Also changing tire size will change the rpm that you cruise at so it will affect your MPG too.