Thanks, RayChez! your last posting has just answered a query I had on this forum months ago. My air pressure (rear gauge) had been dropping to around 65psi then back up to 130psi in a constant cycle, I discovered it was the Haldex blowing off then leaking down to 65psi following an alarming ride out, on very narrow (hedges brushing both sides!) British country lanes, I had a sweat on because I believed the air brakes would, of course, come on when the pressure goes, we would have been stranded very dangerously on roads with tight bends, and not much wider than the coach!
I was so relieved when it stopped dropping at 65psi.-I've not had a definitive answer to my "Is this normal?" question before, so if an experienced RV garage foreman says change the filter..there's my answer! Many thanks. This forum is like a lifeline to me, there's relatively little info. on RV's here in England.
1997 32' Sunvoyager DP(extensively modified!)
Spartan chassis. Cummins 275hp.