Community Forums

Kmw · 08-08-2020, 05:47 AM

Hi all! First time diesel pusher owners. We have a Tiffin Allegro Red 33AA. First major trip on our way from NV to ME. Last two days the air ride suspension has deflated while driving. First time on freeway with rough pavement doing about 60, 2nd on a highway doing about 40. Is this normal?? What might be the cause?

CountryB · 08-08-2020, 06:56 AM

That is not normal.

When the suspension loses air does it lower/drop at all corners or just one side/end? Does it level back out on its own?

Can you describe what is happening in more detail?

Without more info, I would guess there is a malfunctioning air ride control valve (RHCV). There are usually two RHCV in the rear and one for the front axle. Your Coach uses the freightliner chassis. Possibly one of the valves is dumping air when your coach rocks due to road surface changes and the valve is dumping air when it shouldn't. Some RHCV have a built in delay so the valve doesn't overreact to coach movements on rough roads.

Kmw · 08-08-2020, 09:09 AM

That’s kind of our guess too. Seems to be back, not sure I’d the same side each time. Happens on rough roads and in a slight turn. Does not fix itself. We pull over, put jacks down, then start over and so far it has fixed the issue.

CountryB · 08-08-2020, 09:58 AM

Do you have air leveling? I've seen problems with the HWH leveling manifold "travel solenoids" sticking. This could only happen if your leveling system has a Travel mode.

If your Coach is "jacks only" leveling, your coach probably dumps the air bags before leveling. If that is the case, your dump valve may be going bad. Since your putting the jacks down to relevel, that makes the system cycle the dump valve which is then unsticking it.

When you pull over to fix the issue, do you hear any air leaking around the back or front of Coach?

You may need to pull over and shut off the engine to hear anything.

Kmw · 08-08-2020, 10:26 AM

We’re jacks only. We have heard air leaking. Today we were on freeway & didn’t get out of rig.

Martind4 · 08-08-2020, 10:40 AM

Call Freightliner Help line and they can direct you to nearest service shop. You don't want to drive with suspension deflated, it's hard on the driveline and cause more problems.

800-385-4357