cab air springs

[Ukraine Train]

Can I get a quick summary of this system? How does it work and how should I use it? The TM's have repair information but I didn't see anything about what the system does. When I got my truck, the bags were pinned, and I've left them that way so far.

 

[Suprman]

The manual does describe it. You can unpin them for road driving there is a control at the bottom of the bottom right of the manifold box that will inflate them. They cushion the cab when driving.

 

[Ukraine Train]

So the control knob needs to stay locked in and the level sensor triggers inflation only when needed?

 

[Suprman]

I leave mine locked in and on all the time. The manual says to deflate for offroading though. I think its a simple system im not sure there is a sensor I think they behave almost like a shock absorber.

 

[Overdrive]

The ride is MUCH BETTER with the cab air springs engaged (on) and working. When I first got my LMTV I didn't have them inflated and driving down the road made it seem really squirmy on the road.

It seems like, on my LMTV anyway, that after shutdown, maybe 3 or 4 minutes, the cab lowers back down. It is a quick action when it happens so it doesn't seem to be any kind of air leak and a day later when I fire the truck back up the air tanks are still close to full. Possibly a time delay thingy?

Same as Suprman I leave mine locked in all the time.

 

[Suprman]

I wonder if they wont take air from the system to keep them up unless you have a certain pressure already. To preserve air for braking if air supply is low for some reason.

 

[Ukraine Train]

As long as you don't have leaks I assume they don't take any air after the initial fill.

 

[Suprman]

I think they have air pressure to them when the truck is running and they are engaged

 

[Lmtv772]

The cab suspension uses the air from the tire inflation circuit, not from the brake circuit.
Later years don't have that button at the manifold anymore (at least not the MTV), So they'll always inflate.

 

[country]

Not sure if you need, but we do stock these

Dave
www.easternsurplus.net


FM-151 | Air Spring, Cab Suspension, Left Side
Left Side Cab Air Spring Assembly for FMTV
NSN #: 2510-01-481-7663
Part #: 12421438-004
Price: $595.00

 

[Lmtv772]

Not sure if you need, but we do stock these

Dave
www.easternsurplus.net


FM-151 | Air Spring, Cab Suspension, Left Side
Left Side Cab Air Spring Assembly for FMTV
NSN #: 2510-01-481-7663
Part #: 12421438-004
Price: $595.00

wow!!!

 

[MaiNiaK]

Business must be down or something...

 

[country]

Thanks for looking

Dave
www.easternsurplus.net

 

[Suprman]

Boy you guys are all funny

 

[KNINE]

well I have an issue related to the cab suspension... When I disengage my parking brake the cab goes down. When I engage the parking brake the cab goes up. Any thoughts on how Ican fix this?

 

[Suprman]

What do your air gages show with the park brake off?

 

[KNINE]

if I remember correctly about 120 PSI

 

[Suprman]

If they drop when you release the brakes that could indicate a loss of air somewhere. Do they come right back up?

 

[KNINE]

No. They stay down when i drive... They are up when i park.

 

[Suprman]

With the parking brake off the truck cuts air to the hydraulic control box, as a safety so you cant raise the cab unless the truck is in park. There should be a separate air feed to the control for the cab air shocks. Maybe someone switched the two air lines to the box.