I have been maintaining a sterling lt 8500 tri axle for a while now and the boss has been complaining about the brakes not releasing when the lift axle is coming up causing the tires to skid when cornering. Does anyone know where I can find a air system schematic, or point me in the direction of the suspect valve or control. There should be something that cuts service air to brakes immediatly when axle lift is initiated. Please help tires are taking a beating. thanks in advance
What year? I have the factory service manual for 2000. We don't run lift axles so don't know much about them but I would have thought it would be aftermarket and not factory installed so the factory manual wouldn't help.
i would find out the make and model of the lift axle suspension and start with that manufacturers website
Yes if you find this out please let us know. I have had dump trucks quads/Triaxles for 12 years and I never heard of these trucks having a valve for brakes. I have a 2005 Sterling quad and there is nothing for lift axle brakes I adjust my tag ax;es brakes, a little looser, than the back drive axles, so the lift axles dont lock up first Keep us posted, I would like to install this valve
I have a 378 peterbilt with a sterable lift I think it just uses abs sensors to stop the wheels from draging. Mine wont drag even on gravel as I lift it I think they started using abs around 96 or 97 on class 8 trucks. Hope that helps.
I will get year and more info on truck today i hope.
Man dont get caught with that valve your talking about installed on a truck by DOT. The problem your talking about is easily remedied, All you need to do is learn how to drive a truck with a lift axle. Use brakes to slow down, then lift axle when cornering. Yes it takes planing, slow down to desired speed before the turn, then you dont need to ride the brake through the corner to keep from rolling over. If you ever get into an accident with extra non oem brake valves that cut off your brakes they will hang you, your fault or not.
Braking while the lift axle is going up and or down will cause the wheels to skid. This is probably the number one cause of flat spots on lift axle tires (after having all your other brakes out of adjustment causing the lift axle to lock up first during heavy braking). I have never seen a lift axle where there brakes did not work all the time, no matter if the axle is up or down. The lift axles on our trailers will even fully apply the brakes when the trailer parking brakes are set.
Thats why in Ontario lift axles are being phased out. Can't use them at all on a gravel trailer any more.People did not know how to use them. Now the axle must be self steer and not adjustable from in the cab.
Actually, they're not being eliminated Ont. reg 457/10, section 5 governs the use of liftable axles. Raw forest products haulers being exempt Brakes locking up on liftable axles is correctable. It requires replacing the air control valve. Basically it cuts the air off to the service brakes when the axle is lifted. It is available from many aftermarket suppliers. Up here in the great white north anyways:canada
thank you for the input, is there any chance you would have a schem of air system or point me in the direction of this control valve? Oh ya and this fella has been driving for 50 years of more and I don't at all so I won't be telling him how to drive or I'll get told off. And I don't think there is any valve that is non-oem on the truck so mto shouldn't be a problem
Don't think there is a maxi on the lift if I remember correctly.
I was at my local truck parts shop today and a salesman to Bendix brakes was there, I asked him about this issue. He said to call their tech support and they could help. He has heard of this, but he didnt have details Tech support 800 247 2725 maybe we could get them on this forum