New Air Bags & Sway Control = ROUGH ride

but guys...in the RV world don't we blow anything that holds compressed air up to MAX for SAFETY ?

seriously - as many have posted air bags are air springs, increasing pressure in them increases the spring rate etc.

If you carry heavy axle loads requiring fairly high air pressure in air springs removing the "gas" shocks and going to hydraulic shocks can settle down the pogo stick effect.

tcp wrote:
Fyi: the firestone airbags are rated as 40lbs of weight capacity per psi. at 40psi you've stiffened your rear springs by 1600lbs. that is a lot. i run mine at 8 psi unloaded to support my topper and 18-20psi when towing.

f250s with E rated tires have specified 50 psi as a front pressure in the past with the rears set as required for the weight. not sure if they still do this now.

i would try all the tires at 50, the airbags at 20, and adjust the wdh so the front stays at normal ride height.


2009 XLT (XTR pkg) supercrew 5.4l 6sp 6.5ft bed.
90k miles, Raider Topper, Ride Rite airbags, Ford well liners, 5Star SCT Tune, NGK Iridium IX plugs, Bilstein 5100s all around.

Absolutely spot on! This is exactly what I discovered, 25PSI in the bags was by far the best feel for me. By your math (and I didn't know the 40lbs per pound rule) 25PSI equates to 1,000lbs and my TW is right on 1K.

Thanks for the confirmation, sounds like we're all on the same page. :)

Drew_K wrote:
Couples of thoughts here:

As suggested already, measure the height of your front and rear wheel wells empty (no trailer), with the trailer but no pressure in the air bags, and then with the trailer at the air bag pressure you've been towing. If the rear height with TT and air bag pressure is above the unloaded height, I think you have too much air bag pressure.

Did it today and was pleased with my numbers.... sort of.
Loaded w/ TT and bags at running pressure (I've settled on 25lbs before hooking up, it feels good towing and sits well):
Front is within 1/4 inch of stock, and rear just under 1 inch (7/8") lower than stock (stock meaning no air, and no TT).
To me that sound just right.

However, I didn't measure with the TT and no air... only with air. I think that the bags bring the rear of the truck up a little, maybe 1/2" or so? Not much and I don't feel it's a bad thing...
I'll measure that next time.

Drew_K wrote:
Couples of thoughts here:

I'm a big fan of E rated tires even for a 1/2 ton. They are much stiffer than D tires; however, I wouldn't run the E tires at low pressures, like 40 psi. I pump mine up to 75 PSI in rear when towing.

Now that's interesting. I never did run mine up over 50 or so (TV tires)... I think next time I'm out I'll push them into that 70 range and see how she goes. Thanks for the thoughts.

Fyi: the firestone airbags are rated as 40lbs of weight capacity per psi. at 40psi you've stiffened your rear springs by 1600lbs. that is a lot. i run mine at 8 psi unloaded to support my topper and 18-20psi when towing.

f250s with E rated tires have specified 50 psi as a front pressure in the past with the rears set as required for the weight. not sure if they still do this now.

i would try all the tires at 50, the airbags at 20, and adjust the wdh so the front stays at normal ride height.


2009 XLT (XTR pkg) supercrew 5.4l 6sp 6.5ft bed.
90k miles, Raider Topper, Ride Rite airbags, Ford well liners, 5Star SCT Tune, NGK Iridium IX plugs, Bilstein 5100s all around.

Couples of thoughts here:

I'm a big fan of E rated tires even for a 1/2 ton. They are much stiffer than D tires; however, I wouldn't run the E tires at low pressures, like 40 psi. I pump mine up to 75 PSI in rear when towing.

As suggested already, measure the height of your front and rear wheel wells empty (no trailer), with the trailer but no pressure in the air bags, and then with the trailer at the air bag pressure you've been towing. If the rear height with TT and air bag pressure is above the unloaded height, I think you have too much air bag pressure. Also, it's tricky adjusting a WDH along with airbags because adjusting the airbags by definition also adjusts the WDH. Too much air bag pressure and you basically take away what the WDH is doing.

I run my airbags at 25 psi for my enclosed car trailer and 35 psi for my TT. I realize my setup may be completely different than yours but just to give you some additional data points.

mkirsch wrote:

VegasScotty wrote:
Bigger almost always fixes stuff, but it isn't always a practical answer.

That little snippet of wisdom didn't prevent you from buying that bigger trailer now, did it?

That's funny... but true! But I love the bigger trailer. I think goducks might be on the right track... some trailers are just built differently and don't tow as well.

We made the trip back from ND to NV last week and all was well. Different roads and guess what? Much less bounce.

I've thought about it and I think I'll move up to 1000 or 1200lb spring bars. I currently have the same ones from my last set up which was a couple of hundred pounds less TW. The 800lb bars I'm using definitely flex and that of course could be some of the bounce.

Other than that everything is great. Following most of the advice I lowered the air pressure as I mentioned to about 25-30 in the bags (before hooking up) and took out a little in the truck tires and if the road is good the ride is good, so I think the setup is pretty sound.

mkirsch wrote:

BTW, it looks like you've got everything cranked up so tight the truck is riding at unloaded height... You might have too much WD applied, which also causes a rough ride.

The 4x4 sits pretty tall... it's 1" lower in the back when loaded and just slightly lower in the front... less than 1/2 an inch.

VegasScotty wrote:
Bigger almost always fixes stuff, but it isn't always a practical answer.

That little snippet of wisdom didn't prevent you from buying that bigger trailer now, did it?

Just sayin'

BTW, it looks like you've got everything cranked up so tight the truck is riding at unloaded height... You might have too much WD applied, which also causes a rough ride.

With your bags aired totally deflated, measure the height of your rear fenderwells.

When fully hooked up with spring bars engaged and air in your bags, measure the height of the rear fenderwells.

Height of the fenderwells SHOULD NOT be any higher than unloaded height.

My guess is that the new tires, plus possibly a bit too much air, is making it ride rougher than you are used to.

You need to also remember that your WDH will need readjusting due to the change in rear ride height from the bags (unless the height isn't changing at all). Change in rear ride height changes the amount of angle between TT and TV, which removes some weight off the front of the truck.