Airbag PSI Method

[timelinex]

I've got a 2020 Ram 3500 that I'm using to pull a 5th wheel that's about 19k LB with ~3k Pin Weight.

I just got some Timber Grove Airbags. Install was great and they seem to work exactly as intended.

I am having trouble figuring out how much PSI to use. I called the owner Steve at Timber Grove and it's pretty Amazon customer service that he personally picks up. He told me to measure something on the back and just get it back to that height....I confirmed with him if that meant "tail high" and not actually level and he said yes, back to stock height. At 80 PSI I'm not quite back to stock, but getting close. However the issue is that because of it being tail high the very rear of the bed is already only 5" away from the 5th wheel. I may call him again, but don't want to be a bother.

I am trailering later today. Any advice on figuring out a good PSI?

[Cumminsfan]

I wouldn't put any more psi in than's needed to bring the truck to level. I wouldn't want my truck aired up back to the OEM height in the rear. There's a reason that the rear of the trucks higher than the front empty. It's to compensate for a heavy load.
As to the 5" clearance, can you raise the 5th hitch? Thats easier than trying to lower the pin box. Raise the hitch up an inch. Then hitch up and see how the truck sits and adjust the bags so the trucks level. Being a 3500 I doubt you'll need much air added to the bags.

[darrellr]

Exactly as said, just keep the truck level if you can. Don't go back to non-laden height of the truck. They are designed to have a bit of sag to bring them back down to level with load.

[timelinex]

Originally Posted by Cumminsfan

I wouldn't put any more psi in than's needed to bring the truck to level. I wouldn't want my truck aired up back to the OEM height in the rear. There's a reason that the rear of the trucks higher than the front empty. It's to compensate for a heavy load.
As to the 5" clearance, can you raise the 5th hitch? Thats easier than trying to lower the pin box. Raise the hitch up an inch. Then hitch up and see how the truck sits and adjust the bags so the trucks level. Being a 3500 I doubt you'll need much air added to the bags.

That's what I always thought, and when I asked that, he insisted the correct way was stock height!

Right now the trailer is about level, give or take 0.25 degrees or so. I can raise the hitch, but then the problem will be the trailer will be nose up by that same inch. Isn't riding nose up a worse issue? Especially when I am already having issues of being light on the pin weight (toy hauler).

[Cumminsfan]

I towed a 5th wheel for 6 years with the nose about 1" plus and had zero issues.
My pin was much lighter but I had a 2500 so that worked for me.
I can say that I very rarely ever see a truck towing a 5er when the trucks rear is 2-3" higher than the front. 99.9% of the time the trucks either level or a skoosh low in the rear. Not sure how your F350 sits but my Rams were almost exactly 3" higher in the rear.
I've always read that you need to account for the drop in the rear when setting up the 5th hitch and the pin box in relation to bed side clearance.

So is your truck sagging in the rear?

[jacknife]

You put 80 lbs and you will have a lousy ride . Get it the truck level and drive it . You can experiment with what lbs gets you the best ride and control .

[Dave Pelletier]

Originally Posted by jacknife

You put 80 lbs and you will have a lousy ride . Get it the truck level and drive it . You can experiment with what lbs gets you the best ride and control .

Yep, this. ....an no, never try to restore the ride height to "empty truck".....level is just fine.

Dave

[CamperLifer]

Don't overcomplicate it. Hitch up with the airbags almost zero PSI, whatever the safe minimum is. When you are all hitched up and loaded ready to hit the road, increase the PSI until the truck and trailer are level.

[kdauto]

I'm sorry but I just have to ask: I imagine this is a dually 3500? If so, may I ask why you even felt the need for airbags? These trucks are designed for hauling, and, as mentioned above, that extra rear clearance is made to be squished down when hauling.

Your u-joints and such are designed to be at the proper angle when there is load, and squat to the rear end. Why anyone would want to tow with the ass end in the air is beyond me.

You can easily squat the rear 3-4" and be fine, and the ride will possibly be better than trying to stiffen it back up in the air.

Also, if your pin weight is really only 3000lbs for a 19k trailer, that is very light. Proper pin weight would be in the 3800-4000lb range unless you're hauling something special.

[kyfarmboy]

Originally Posted by jacknife

You put 80 lbs and you will have a lousy ride . Get it the truck level and drive it . You can experiment with what lbs gets you the best ride and control .

80 psi would probably be like it was all solid, no give, defeating the purpose of the air bags

[MtCamper]

When I had a 2500, it went onto the overload spring when I hitched up the camper. I inflated the airbags just enough to get off the overload spring.