towing advice needed (WHD, air bags, air pressure)

[tmsbandman]

Hi all. I need some advice on how to set up. Here's the hardware:

TT-1991 300BH (30ft)
TV-2004 F150 SCrew (5.5 ft bed)
hitch-Equal-i-zer rated up to 10K lbs)
TV has Air-Lift ride control installed (yesterday)

Last summer I towed TT from Atlanta area to Destin. Hitch weight was 900+ lbs, which was a little much (percentage wise) for the TT, and put my 1/2 ton truck very close to GVWR. I adjusted the WDH pretty aggressively to handle the weight. I am hoping that the air-lift will reduce squat a little and help. I do realize that air bags don't raise my GVWR. The tow rating of the truck is not an issue, but the GVWR is. My questions are:

1) How much air should I put in the bags before hooking up? Or should I with until after? Won't the weight of TT change the air pressure in the bags?

2) with the addition of air bags, should I be able to back off on the torsion bars of WDH?

3) Is it imperative that TT be level (or front slightly lower) for safety? I'm thinking yes, but it's worth the ask. Just trying to get a little weight off TV if possible.

4)weird thought of the day-fresh water tank is in front of axle, but gray and black are behind. What if I put water in them "for the road?" Handling issues?

Thanks in advance.

[Rustic Eagle]

Sounds like you have a handle on your TV/TT's weight limitations, especially your GVWR.

Referencing your questions:

1) Prior to hitching the TT, the air bags can be set at the manufacture's minimum PSI, once the WDH is engaged then increase the PSI a little if required. Let the WDH do most of the lifting (rear of TV).

2) The air bags won't have any notable effect on the WDH adjustment (after a "little" PSI increase) as long as the initial weight distribution adjustments were made with the manufacture's minimum PSI.

3) Your correct, TT level is ideal, a little tongue down is acceptable as well. Any tongue "high" condition will enhance the effect of a sway condition should it occur.

4) A couple of gallons in the fresh water tank "for travel needs" shouldn't be an issue. If your TV/TT has the WDH adjusted based on a "no fluid" condition the addition of fluids (i.e.; full fresh water tank and/or black,grey) may effect the TV's handling of the TT, and/or compromise the effective WDH's initial adjustments.

In the case of a automatically controlled leveling system, it should be turned off during WDH adjustment, and also hitching TT/engaging WDH. Confirm with the manufacture.

Bob

[tmsbandman]

Thanks. So the air bags are only for stability, and not actually bearing any of the weight?
BTW-I'm loving the way the truck drives with the air bags. I've got about 12psi in them just to firm up the rear of the truck (12 psi did not lift it at all.) The rear of my truck was way too soft for my liking.

Also-how much should I increase tire pressure for towing? Max on the tire is 50. I normally run about 38 unloaded.

[WVDusty]

On your tire ? I run my tires at MAX pressure any time I am pulling our trailer.

[Rustic Eagle]

Originally Posted by tmsbandman

Thanks. So the air bags are only for stability, and not actually bearing any of the weight?.....snip

Actually the air bags will be supporting some weight, just difficult to calculate how much when there is a WDH in the equation. They will be supporting the cargo weight in the TV box, and some of the weight-effect from the TT tongue weight after the WDH is engaged.

IMO rear air bags can in cases of soft suspensions enhance a TV's handling when carrying heavy loads and/or towing.

Check your TV driver's door for recommended tire pressures under increased loads. I think you will find (especially with "P" tires) that increasing the cold tire PSI will enhance TV handling.

Bob

[clutch]

I measure the hitch height before hooking up the trailer. After hooking the hitch I measure again and add air until I am close to the original height. Then I install the WDH bars and I have very little rear end squat.

[Subaru297]

Do you know the total weight of the trailer from a scale? If you are too high % wise on the tongue weight your best option would be to repack the trailer and move some weight back.
On our 281BHS I have to keep the front pass through storage empty and load up the bunk beds at the back for travelling. Otherwise our tongue weight is too much.
Is your tongue weight estimated or from a scale?

[eldermike]

When I was pulling a 30 foot trailer with 1/2 ton F150 I went up to the 12K bars on my Equalizer hitch. It made hitching eaiser and got my front end back down close to spec. The air bags will help you hold up the rear but you also need to be looking at weight transfer back to the front end. On level ground you can measure your unhitched distance from wheel well to ground and then look at it after hitching. It's not a perfect way but it's method that will get you close enough. Stopping the rear squat will not change the front end lift, only your weight spring bars will do that.

Also for some reason Ford builds trucks that do not sit level front to back...So measure your truck unloaded and notice it's not level to begin with. Then work from there with the idea that hooking a trailer to it is not going to level it but you can put it back where it was.

My hook up looks like it's squatting in the rear of the truck.......however a bubble level on the trailer says its about level (slightly low in the front). The F250 I own looks like it's squatting without the trailer so when hooked up it's not going to improve that condition. But to the eye it's not a flat line from front of truck to rear of trailer. But that's how it is.

I suggest you find a long flat spot and take some tools along. Measure everything and write it down. Hook up and measure again. The bags will cure the squat and the bars should re-load the front end. You might have to break the hitch down and try a few changes to get there, thus the tools you brought along.