Air bag pressure

[mikke60]

I’m sure this topic has been talked to death, but I would still like some feedback . I have. 1977 Gmc 35’ coach with air bags. The previous owner never got me up to speed on a lot of the systems, so here I am. I am currently running bags at 65 lbs,  if it seems a bit soft. Any advice would be appreciated. Mike

[tr206]

The air bags are control by leveler valve or valves you need to set them to the correct height which I have no idea on your bus and your good to go. The levelers adjusts the air pressure in the bags to weight of the bus to keep the correct height at all times. You don't just set a pressure or your the pinion angles for the driveshaft will be wrong. Somebody here I am sure has the correct info for you.

[mikke60]

No levelers. Previous owner installed valves and gauges for each corner

[luvrbus]

No levelers. Previous owner installed valves and gauges for each corner

No leveling valve sounds like you leveling system for when parked

[Dave5Cs]

I put in the same system and keep the front at 85 and the rear at 80  when driving unless a steep curve then just level out myself if needed but when in an rv park or BDing level as much as needed and if not enough add blocks etc.
Goodyear bags say you can put in up to 120 but they suggest no more than 100. I tried that and it is just to hard.

[dtcerrato]

I'm thinking if air bags are kept 100 to their max, if there was a road condition to throw the bus in the air like some of the frost heaves we've experienced on the Alcan - just before the rebound I can see the bags exploding with instant blowout which may even prevent the passengers from hitting the ceiling!

[Tom Y]

Look for a ride height in a manual and set pressure accordingly. 

[Utahclaimjumper]

 I had my 06 that way and kept 65 in front and 70 rear,, a better way is to set the ride highth at each corner,, then note the pressure at each gauge and mark that point on each gauge face so you can duplicate it..>>>Dan

[dtcerrato]

Our oem leveling valves are still as designed. We added solenoids to dump air at any one of the three leveling valves to manual level when parking or camping. It works well.

[luvrbus]

I had the system on 2 buses a 5 and 8 I got from Gary Nickerson ,my 3 leveling were still in play,you guys are saying no leveling valves ? that would suck

[Tom Y]

I had the system on 2 buses a 5 and 8 I got from Gary Nickerson ,my 3 leveling were still in play,you guys are saying no leveling valves ? that would suck
[/q
That is the way I set mine up, it does not seem to change with water tank or sewer full or empty.

[mikke60]

Thank you for all the feedback. I have been running at 65-70. I will bump a bit and see how it works. Thanks!!

[tr206]

try this site. https://gmc.mybirdfeeder.net/GMCforum/index.php?rid=0&t=msg&th=10230

[windtrader]

There are many that report using levelers to adjust the air bag pressure. Obviously a requirement is no leaking bag for it to work. I'm guessing the leveing pressure adjustments do not affect the coach movement. What happens in our bus is if someone is walking around or making some movement the bus moves very slightly, just enough to notice sometimes. Is having hard jacks between ground and frame the only way to eliminate any sway?

[RJ]

try this site. https://gmc.mybirdfeeder.net/GMCforum/index.php?rid=0&t=msg&th=10230

tr206

That page is for the GMC Motorhome, has no relation to GMC Buses!

FWIW & HTH. . . 

RJ