We bought a Chamberlain countryman 6100 with a perkins 6.354 engine. We have changed all the oils on the tractor except for the pto clutch oil. It says it needs: C.J.D. ASD PTO OIL Part No 65159. I have googled this but to no avail. Being a tractor from the 60's, its hard to find info on what oil to replace it with. Can we just use our normal 10w30 utto which is suited to wet clutches?