03-03-2010, 08:18 PM
add the 5-30 and the 10-30 to get 7.5w/60 (each side requires a special calculation that only I know).
Otherwise... I'd keep using 5-30 just like it says in the manual.
The only time I switched on OLDER 4 cyl (Mitsubishi 2.6, from 1980) was to 20w/50 in the summers
that were blazing hot, (the car had a flat black hood). In the winter I had to search out 5-30 back
then, otherwise use 10-30.
Otherwise... I'd keep using 5-30 just like it says in the manual.
The only time I switched on OLDER 4 cyl (Mitsubishi 2.6, from 1980) was to 20w/50 in the summers
that were blazing hot, (the car had a flat black hood). In the winter I had to search out 5-30 back
then, otherwise use 10-30.