Not recommended. Use 10w30.
if it si 15w40 engine oil
12 quarts 15w40
12 quarts 15w40
Gas 10w30 Diesel 15w40
Yes, you can mix conventional oil with synthetic oil with no problem.
Can be either Mobil 1 0W40 or Any name brand 15w40
5w20, 5w30, 15w40. It depends on the engine and operating conditions.5w20, 5w30, 15w40. It depends on the engine and operating conditions.
I use 15w40
15w4015w40
12 quarts of 15w4012 quarts of 15w40
5w30
Only the weight of the oil, 20w 40 is thiker than the 15w40, 20w 40 is the best oil for the old cars although 15w40 is very easier cold start ...