P38 Auto gearbox fault

hi
Need some help please. I changed the fluid, cleaned filter as it was new last year, changed ECU under passenger seat. As soon as the engine is warm we get a gear box fault. The gear box stays in one gear all the time now. The gearbox oil was black when I changed it. Suggestions please!

Diagnostics - with luck there is a stored code telling you what to look for.

Black oil is not a great sign, it indicates the oil has lost its 'oil' properties and the clutch plates are probably worn and rife with heat damage.

I assume the fluid level was checked correctly?

Saint.V8 said:

Diagnostics - with luck there is a stored code telling you what to look for.

Black oil is not a great sign, it indicates the oil has lost its 'oil' properties and the clutch plates are probably worn and rife with heat damage.

I assume the fluid level was checked correctly?

Click to expand...

black oil indicates burnt clutch plates

You might get lucky with some Lucas Transmission fix and a flush but burnt clutch plates doesn't sound good.