i am driving a 99 suburban w/ 6.5 turbo diesel it has had redline 15w40 in it since about the 20k kms i want to change the brand because in canada i pay on avg $13-16 per litre need some recomendations Mobil 1 5w40 syn was recomended but no sure about the 5w instead of 15w
i have been reading...
