Midland Style KN20031 Push Pull Valve

[RCG604]

Hello, I have a leak in my emergency brake valve. I pulled it out and took some pictures of which are attached. I have found several with a google search. Amazon has one for sale but it says the pop is 7-17 psi but I found on other sites they list it as 25-35 for the same part number.

Is the Amazon listing wrong or ?


Thanks

Richard

[barmcd]

They come with different values. The Texas CDL handbook says the parking brake should pop between 20 and 40 PSI so the one on Amazon won't meet that standard. That would be a consideration if you were in Texas, other states might not matter.

[Spk64]

Originally Posted by RCG604

Hello, I have a leak in my emergency brake valve. I pulled it out and took some pictures of which are attached. I have found several with a google search. Amazon has one for sale but it says the pop is 7-17 psi but I found on other sites they list it as 25-35 for the same part number.

Is the Amazon listing wrong or ?


Thanks

Richard

Are you sure you have a leak in the parking knob valve?
The reason I ask is I thought mine had a leak and it ended up being a blown diaphragm on the spring brake. Leak got bad enough the parking knob would not hold to disengage the spring brakes.

[RCG604]

Originally Posted by Spk64

Are you sure you have a leak in the parking knob valve?
The reason I ask is I thought mine had a leak and it ended up being a blown diaphragm on the spring brake. Leak got bad enough the parking knob would not hold to disengage the spring brakes.

I am pretty sure since I can hear leaking around the shaft and if I wiggle it then it stops leaking.


I did some further research and found out the one listed on Amazon has the wrong part number KN20031 does have a pop of 25-35 psi but KN20033 has a pop of 7-17 psi.

I called the sellers toll free # and found out it is a 25-35 pop and they just listed that part of the information wrong.

Thanks for the input!

[Kurt Averill]

Be carefull Richard - had the same issue with mine and bought one off Amazon - turned out to be a cheap knock off - fine print said it was a kn20031 replacement - got the real thing at a local truck parts place.

[Poormarky]

I sold truck parts for over 30 years. I wouldn't trust much of heavy duty truck parts from Amazon. Now you can go to Napa and Oriley's along with truck dealers and Parts distributors. In most cases they will have the parts replacement you need.
Just my 2 cents.