1994 c3500 Dually. Can't find PROPORTIONING VALVE

[94DUALLY]

Hello,

I'm sure I'm not the first to need one. No one seems to have one at the local part stores or even online.  Someone have a part number that will work?

Thanks,

Raul

[davester]

maybe get a used one from a junkyard or used-part place?

[94DUALLY]

UPDATE. Found one on Ebay and has worked great except for the sensor oring failure. Replaced the oring and up and running again. 

[94DUALLY]

UPDATE. The o ring has to be continually replaced. Any solutions out there?

Also, I'm assuming 88-94 chevy/gme trucks should be the same part.