Using gearbox oil ??

[drzjohn]

Went for a ride tonight and 4th gear got well noisey, got home and checked gearbox oil and it was very low, topped it up went out and it sounds better.
Is it possible for the gearbox oil to get into the crankcases ?
I have not noticed more smoke out of the exhaust than normal.

[looey]

It would be crank seals if it's sucking up and burning geabox oil but you'd see extra smoke unless it was very very little over a longish period of time ?.

[drzjohn]

thats what i thought, the crank seals are new and it has only done 55 miles since rebuild