I have replaced the box with no probs and it has been fine for 3 weeks. But all of a sudden its started to get hard to put into gear. When the engine is turned of its fine, and the also fine when it first turns on. But after it warms up is when it starts to get hard.

Do you think that it might need more fluid, because i checked it and it wasnt leaking out, so i assume that means it is not full, if its not this what else should i check?

Cheers