I noticed while putting my plates on my new truck that there are 2 air valves to the left and right of the rear license plate. I've checked and there is air at the valves but have yet to find the compressor or tank, but I have yet to crawl under the truck due to the weather here and the fact that the dealer sprayed some rust proofing on the underside of the the truck and everything is coated in an oily sludge. I know I will when I finally get under the truck, but in the meantime, I was wondering if anyone might have some idea as to what this may have been used for? I've never seen such a set up but am now thinking about a good set of air horns..hmmmm

 

Air shocks or lift bags?

 

Again, I haven't been under the truck yet....If that were so, I suppose the valves could be to release air, but I'm sure they would have a better system than that for airing down......I may just have to crawl underneath and follow the air lines.
I was underneath last week to change the oil, but wasn't thinking about it at the time and I can spot nothing under the hood.
I certainly don't hear any compressor at any time. Was just thinking about it, so thought I would post and see if anyone knew.

 

x2...most likely air shocks in the rear, there's a schrader for each side.

 

I'm gonna check that out today if I get a chance....Let ya'll know what I find...
Thanks!

 

Sounds like air shocks to me as well.
I ran them on my Camaro back in the day. No fancy compressors, tanks or switches, just a couple of valves in the trunk.

 

Hey guys.....you were right about the bags.
I took a look yesterday and I saw the air bags c/w two lines to the rear bumper. I am not familiar with the setup and always thought that you would have a control in the cab for something like that.
In any event, I will look around to see what I can find out on them and what is a good pressure to keep them at...etc, etc,....
Combined with the 4 large bolt holes in my bed, I am now assuming that a previous owner had a 5th wheel setup.

Who else has these????

Under normal driving conditions, would these make a noticeable difference over stock. I drive the truck daily, but have no idea what it felt like stock, so I'm wondering.

 

Hi there,

I had air helpers in my old Durango. Worked wonders for me when towing trailers. For everyday use I just kept about 25lbs in them to make sure they kept their shape. Mine had a maximum pressure of 100lbs. For heavy loads I'd pump them to about 80-85. Anything more than that and it was a HARD ride. You have to make sure you do them evenly, or risk premature wear on parts.

Thing is, some compressors have a tough time at pressures around 100lbs. It won't work at a gas station air pump for example.

If there's no pressure (no air) in them...no different than stock. If the truck squats a bit from worn springs, keeping some air in the bags will raise the height at the back a bit.

 

I had that setup on air shocks on a '71 LTD that I upgraded to a tow vehicle..

Like the above poster said, keeping them at 20 or so psi will give you a normal ride.

Then, if you do put a load in the truck, just air it until it is level.

The only thing I would change is to Tee the 2 airbags together. That way you only have to fill at one fitting, the pressure will be exactly the same on both sides, and, most important of all, if one side should leak while you are moving, both sides will settle down together.

Having 100 psi on one side and 0 psi on the other is not good. Tie them together.

 

Thanks for that info guys!
I haven't checked the pressure yet. The truck sits fine and the springs seem good. You can get a good look at them in my garage.
I'll grab my air gauge out of my shop in the morning and check the pressure is. I have a compressor for my air nailers and stuff, which has a pressure regulator on it and goes to 125 psi, so I can adjust as necessary.

All Hat....That's kind of a good point about settling together should one bag leak.
I haven't really done any looking yet and I'm not sure how often they leak.
It's been a busy day.....One thing I noticed about owning a pickup truck....you have all those friends who don't and occasionally need one. That's not to say that I'm not happy to help out a friend if I can.