8030 Power Shift

[gearheadbill]

Am looking at an 8030 power shift. The complaint was that it was slipping in reverse. Tested supply pressure to valve body. It is over 250 at pump supply pressure. Modulator pressure is 130, book shows it should be 210-230. I removed cap from lube pressure relief valve on top front of valve body and spring was broken, replaced it and no change in pressure. The valve body was taken off and nothing else found wrong, no visible cracks or valve issues. Replaced gaskets and retorqued on installation, same problem. Tried to shim up regulating valve spool and nothing changed.

 

[gearheadbill]

Or do you know of someone I could call to talk to? It has been 30 years since working on one

 

[DrAllis]

There is a "C-2" test port on the rear of the trans housing. C-2 is the reverse clutch. There is also a "C-1" test port. It is a forward clutch. Check pressures on both of them