740 & 760 760 ZF4HP22 Red Gunk in Screen

1987 760 with the B230FT engine, ZF4HP22 Auto Trans. Been parked up for 8 years or so.

- Once warmed up it gets a terrible RPM dependant noise in all gears (N/P/R/D)
- Sometimes transmission will not engage a gear (Park will stop it rolling though)
- Red Fibre gunk in pan screen (clogging flow, causing transmission not to engage at times?)

What we've done:
1, Drove around in 1st/2nd gear - started to have issue with noise and no drive.
2, Drained pan, cleaned screen filter - was clogged with red gunk, oil was brown as brown can be.
3, Drove around, went though all gears using lockout (1-2-3-4) and transmission changed flawlessly smooth.
4, Noise again, dropped pan, drained again - Oil was pretty red still, but allot of fine black partials (like what you get stuck to the magnets) in oil. Screen was clogged again.
5, Cleaned screen, drove around, no noise, parked up.

Now, is the transmission buggered? I assume red fibre material is a clutch pack or something that's degraded?

Havent really driven it around in 3rd/4th but 1st/2nd change smooth as, so I assume whatevers breaking down inside is something to do with 3rd and 4th.

Any comments? New Transmission before it explodes itself?



Sign In or Register to comment.