I know this is an older post but I figured I’d pass on what I found out on this. I contacted LS USA customer service today and questioned the use of 80W90 GL5 in my front axle (my manual only says GL4 and I happen to have a few bottles of GL5 on hand). They checked my tractor’s serial number and told me that the GL5 is compatible with my unit.Good point, the specs call for GL4 in front axle. The Lucas I used is rated at GL5 and is a non synthetic. I wonder if using the Lucas will do any harm? When I got the tractor back from a dealer after some warranty work and the front axle was 2 qts low so I used the Lucas to top it off.
Amsoil 80W-90 GL5 is GL4 compatible so no worries there.I know this is an older post but I figured I’d pass on what I found out on this. I contacted LS USA customer service today and questioned the use of 80W90 GL5 in my front axle (my manual only says GL4 and I happen to have a few bottles of GL5 on hand). They checked my tractor’s serial number and told me that the GL5 is compatible with my unit.