ZF lockup problem

[Sheepdip]

My ZF has done around 6k now, lots towing a caravan. Noticed the lockup is becoming sporadic, especially if going straight from 3rd into top lockup, it sounds as though the revs are dropping but I still get slip, then manually selecting 3rd and back into top usually works. If I slowly accelerate so in top before lockup it usually works ok. Seems to get worse when hot. So am I looking at a gbox, Torque convertor or valve block problem?

Cheers

Paul

[stagwingnut]

have u checked fluid level ? they are similar symptoms to low fluid level ,reguards graham

[Sheepdip]

Hi Graham, I did when it first happened and it was where I expected on dipstick, as Clive Tate instructed but it was hot, usually check when cold. I'll add more oil anyway and see if it affects it.

Thanks

Paul

[alan_thomas]

Paul, Difficult to say the lockup clutch is in the Torque converter but hydraulically actuated from the main box so its not easy to point the finger. But because it is On/Off I would first look at the oil levels.
No use to your problem but I am installing the ZF EH box which uses electrical actuation of the lockup clutch on this box its easy to point to the torque converter if it is electrically called.
- Alan

[Seaking]

Hi Paul try this link might help http://www.cowdery.org.uk/zf.php

[Sheepdip]

Hiya, thanks for replies, left Stag for a few days so could measure cold and flat, plenty of oil showing on dipstick, it does lose a little but only drops. Thanks for article on overhauling, I've done BW's before but not one of these, wouldn't have thought it nescessary at low mileage. I'll ring one of ZF spares company and see what they suggest.

Cheers

Paul