My ABS/Traction control valve is leaking at the exhaust port when I apply the service brakes on my 2009 Kenworth T800. The valve is located on left frame rail midway of cab. I replaced it in Dec. because it was leaking constantly. (It stopped leaking constantly but to be honest, I couldn't tell you if I had the issue of the leaking when applying the service brakes right after replacement or not.) But a week or so after, I did notice the foot valve was leaking so I had that replaced. Within the last 2 weeks, I noticed the ABS valve that was replaced in Dec. is leaking at the exhaust port only when the service brakes are applied. I suspected the valve failed and replaced it again. The issue did not correct and is still leaking at exhaust port but only when I apply the service brakes.
Called Bendix, said it has to be a bad valve. Not 100% convinced, and not wanting to have to deal with the PIA return process for a 2nd time, for the heck of it, I replaced the relay valve ahead of this valve and that didn't correct the issue either. Parking brake applied/released has no effect. I've clamped off all chambers one at a time and no change. Chased air hoses, none appear crimped/damaged. Checked fuses, all good.
This valve wasn't an exact replica of the valve that came off of it. That part number was 300317 and this is supposed to be an updated valve with part number K070951BXW. What are the chances of getting 2 bad new valves? Is it possible to have it hooked up wrong? I pulled the line off the relay valve that goes to the ABS valve and don't get any air movement through it at all. Should there be?
Really just trying to get this fixed with as little downtime as possible and without having to keep throwing $300 valves at it while hoping to get a good one, especially if there's something I'm missing. I'd greatly appreciate any advice or suggestions. Thank you in advance.