Hello everyone,
I'm trying to determine the cause of an intermittent gearbox slippage.

To save on the cost of a haul out,
Is it possible to draw the gearbox oil out of the saildrive with a suction pump, via the filler point at the top?

Also, the manual states to use ATF type A.
Is Castrol ATF Dex lll a suitable equivalent?

Hurth Saildrive mated to a 27hp nanni diesel.

Thanks in advance.

Cheers Chris.