air problem

So it sounds as if they (the dealership) did indeed diagnose and fix your problem correctly lol. I frequent that shop often but only for parts. I had my truck in there for service once or twice before, but the wait times are crazy long (3-4 days usually before they'll even look at your truck) which in turn motivated me to start wrenching (and learning) on my own truck. The Yipslanti branch (Wolverine's main) is quicker if you MUST take it to a dealership. So long as they can duplicate the problem I haven't heard anything bad about them and they seem to know what they're doing. There's also a TA in Monroe, MI that's pretty good too if you need certified work done, and they won't make you wait 3-4 days lol.

Anyway, I also recently replaced my air dryer and I get the same pressures you are. It purges at about 140psi. I even used an external gauge and checked both tanks individually to confirm this. 140 IS high imo but it's probably nothing to worry about. Most all the parts dealing with air have a working psi of 150 and a bursting psi of 300+. The safety valve on the dryer will release at 150 I believe so again there's nothing to worry about. You can buy an adjustable governor ($12-$15) if you wish to lower the purge and/or cutout psi setting.

 

that dryer should be purging at 130psi. if you want to test it put a guage on one of the extra reservoir ports on the governor and that ggauge would show you exactly how much pressure the governor is seeing. if it is in fact operating at 150 psi then the govenor could be bad. they are preset on those dryers and non adjustable so you would have to replace it.

 

I had a problem, freighliner Columbia cl 120,2004, Detroit diesel series 60, egr, type engine, Eaton fuller 13 spd , the air was slow building up in the secondary tank, the primary tank would fill up to 125 psi, but secondary tank would stuck up at 45 psi, in spite of pushing the gas pedal air would not build up, leading to gears wouldn't go up the 5th gear,the drain tank point of secondary tank was removed and put on a Guage, air Guage, which told the same story, that's low air pressure, so changed, air dryer, governer, The problem persisted, THE Remedy was to change the primary air tank, one with the wet drain, under driver side, problem solved,4 days lost, anyway that's my story, the crud in the primary wouldn't let secondary fill up

 

Addendum to what I posted earlier, you have to replace a cross type three ways fitting on the primary tank, that's the wet tank, below the driver side, this fitting supplies air to the interaxial differentials, and dumping of air bags, and the shifter etc, I wasn't able to shift to 5 gear in an Eaton fuller 13 spd, the crud was in the fitting too, all OK now back on the road, god bless