Soft breaks on dp

It's BRAKES not breaks. Sorry for this early morning open space in my head. It was even before my first cup of coffee.

Good advice though. At low speed I have instance good brakes but coming from a fairly long stop they seem to fade.

I'll follow the advice given on this forum and if that doesn't work into the shop it will go.

The coach has only 12,000 miles on it. And it is all air drum brakes.

Thanks for all your input.

What air pressure are you seeing on the dash gauges (cut-in to cut-out)?

Pre Trip Inspection Brake Check

Parking Brake Check (Pre Trip Inspection)

Apply parking brake only and make sure it will hold the vehicle by shifting into a lower gear and gently pulling against the brake.


Test Air Leakage Rate (Static check) (Pre Trip Inspection)

With a fully-charged air system (typically 120 psi), turn off the engine, chock the wheels, release (push in) the parking brake button (all vehicles) and trailer air supply
button (for combination vehicles) and time the air pressure drop. After the initial pressure drop, the loss rate should be no more than 2 psi in one minute for single vehicles and no more than 3 psi in one minute for combination vehicles.

Test Air Brake System for Leaks (Pre Trip Inspection)

With parking brake, (all vehicles) and trailer air supply button (for combination vehicles) released (pushed in), apply firm pressure to the service brake pedal. Watch the air supply gauge and listen for leaks. After the initial pressure drop, the loss rate for single vehicles should be no more than 3 psi in one minute and no more than 4 psi in one minute for combination vehicles. If the air loss rate exceeds these figures, have the air system repaired before operating.

Test Low Pressure Warning Alarm and/or Signal (Pre Trip Inspection)

Turn the key to the on position. Rapidly apply and release the service brake pedal to reduce air tank pressure. The low air pressure warning signal must come on before the pressure drops to less than 60 psi in the air tank. If the warning alarm/signal doesn’t work, you could be losing air pressure without knowing it. This could cause the spring brakes to activate suddenly. Only limited braking can be done before the spring brakes come on.

Check That the Spring Brakes Come on Automatically.

Continue to rapidly apply and release the service brake pedal to further reduce air tank pressure. The trailer air supply button (if it is a combination vehicle) and parking brake button should pop out when the air pressure falls to the manufacturer’s specification (usually between 20 to 40 psi). This causes the spring brakes to come on.

Check Rate of Air Pressure Buildup (Pre Trip Inspection)

When the engine is operating at 1800 RPM, the pressure should build from 85 to 100 psi within 45 seconds in dual air systems. (If the vehicle has larger than minimum air tanks, the buildup time can be longer and still be safe. Check the manufacturer’s specifications.) If air pressure does not build up fast enough, your pressure may drop too low during driving, requiring an emergency stop. Don’t drive until you get the problem fixed.

Test Service Brakes (Pre Trip Inspection)

Wait for normal air pressure, release the parking brake and trailer air supply button (for combination vehicles), move the vehicle forward slowly (about 5 mph), and apply the brakes firmly using the brake pedal. Note any vehicle “pulling” to one side,
unusual feel, or delayed stopping action. This test may show you problems which you otherwise wouldn’t know about until you needed the brakes on the road.

Air pressure front and back is about 60-65psi. maintains pressure very well .

bumpus4 wrote:
Air pressure front and back is about 60-65psi. maintains pressure very well .

That is way too low for full air brakes. I know nothing about air over hydraulic. What type of air brakes do you have?

Yup, 60-65 PSI is WAY too low. 110-120 is normal. You have a problem. If both gauges are reading the same, assume it is not a gauge issue.

First suspect is the GOVERNOR. Not expensive or may even be able to adjust your current governor.

How long have you been driving with roughly 50% of proper air pressure???

On edit: Do not drive until you get this fixed!

My low air alarm barely goes off at 65 lbs. That seems way too low and as Wolfe10 suggests this sounds dangerous. If you shut the rv off do you hear any air leaking?

A govenor is easy to adjust or change and not expensive. On a 2013 it is probably under warranty.

Fixing the obvious first, the low pressure may cure the issue. If not I would have them checked professionally. They should stop the rv with ease.

bumpus4 wrote:
Air pressure front and back is about 60-65psi. maintains pressure very well .

This is your problem... surprised you even get it stopped. Has it always been this LOW? The governor is usually located near your radiator/ back of the engine. By taking off the black rubber cap and loosing the jam nut (3/8") you can turn the shaft with a straight slot screwdriver two turns CW and see how much that raises your pressure. You can do this with the engine running and someone watching the gauges. You want 120 psi minimum.

Air pressure way to low. Should be over 100. Get it repaired now.

Look on the right side of the engine, towards the radiator. Easy to locate. The cap could be blue or black. The governor that is. Right side to me is the passenger side.