Correct gov cut-in psi.

I just took the test a few hours ago, it is 100 psi.

 

Let them know that the inflation needs to be between 85psi & 100psi or to the level specified by the manufacturer.

 

In California says before 140psi.. But the school I got it's cuts of at 140psi and instructor say it's a good tast because it didn't go over 140 psi.. would be a pass on the dmv?

 

140 is very generous. Im used to having around 118 to maybe 122 at most in the tanks. At 140? Ha thats enough air to stop the planet from rotating.

 

Get the commercial driver's handbook from the DMV of the state you are testing in. For some reason some states are changing the numbers around. It used to be no lower than 85 PSI was cut-in but now some states are going to Cut-in 100 PSI and cut-out 150 PSI. Very confusing indeed. The answer is in the commercial driver's handbook for the current year in whatever state you're taking your DMV test at.

 

State CDL manuals should have always been 100 psi cut in pressure for trucks. The controlling regulation is 49 CFR 571.121. (Commonly called Part 121) S5.1.1.1 which states “Air compressor cut-in pressure. The air compressor governor cut-in pressure for each bus shall be 85 p.s.i. or greater. The air compressor governor cut-in pressure for each truck shall be 100 p.s.i. or greater.“

It’s been this way since time began. Your DMV instructor is seemingly too uneducated in air brakes to teach air brakes.

 

Oh that may be where I got the 85 PSI from as I drive buses still and I have to know both numbers. My apologies for the confusion.

 

My CA manual says:

5.1.2 – Air Compressor Governor
The governor controls when the air compressor
will pump air into the air storage tanks. When
air tank pressure rises to the “cut-out” level
(around 125 pounds per-square-inch or “psi”),
the governor stops the compressor from pumping air. When the tank pressure falls to the “cut-in” pressure (around 100 psi), the governor allows the compressor to start pumping again.

 

A cut-out pressure test that is at 140 psi or below is a good test. It can cut out no higher than 140 psi if that is what the California Commercial Driver's handbook says. It is interpreted as at/or below 140 psi. Please make sure there isn't any wording in there for buses or combination vehicles.