atv gearbox problem

[bbvw]

Hi people need abit of help with my atv gearbox.

its ok at the start but when ive done about 30 miles and its all warm it goes all stiff and hard to change gear, in to gear and out of gear. anyone had this fault? clutch is all ok and not worn, just changed oil and have no leaks. 

[Nick_S]

I's guess its the oil. What type have you put in?

The 8P on mine at the minute does this, but then the oil is 23 years old

[bbvw]

its got 75/90 which is what it should be i think. 

[djtez]

You get th right amount in the garbox?

[youngprodigys]

oils viscocity changes under heat and load - you may find you have over filled it mate.

3.1 litres should be put into a 5speed atv/cek box and should be SAE 80 or 75W-90 which you have done.

[youngprodigys]

cant answer that - i found the best way was to empty it all out until it was as dry as i could get it and then put 3.1ltrs in:-S
you not got a haynes manual?

[hayesey]

yes rae is right, car on level ground and then fill to bottom of filler plug. chances are if you put 3.1 litres in it'll be over filled because there's still prob half a litre in there that you just can't get out through the drain hole alone, can get more out by tipping the box if it's not on an engine or by removing the black tin cover off the end.

[bbvw]

Its got oil upto the level you all say about so i know its not over full. anymore ideas guys?