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Alex V. · 03-10-2018, 09:50 PM

There is no need for special oil in the trans. for break-in. Whatever quality of fluid you feel is necessary for the long-term is good from the start.

Brad Penn and Amsoil, among others, make high-zinc break-in oil. After the first 500 mi. (which should mean the rings have mostly seated and the cam is completely broken in) I'd run a 1,000 mi. change of a good high-zinc conventional (probably something rated SM) or use a zinc additive but *not both*.

03-10-2018, 09:50 PM	#7
Alex V. Registered User Join Date: Mar 2013 Location: Campbellsville, KY Posts: 888	Re: Royal Purple There is no need for special oil in the trans. for break-in. Whatever quality of fluid you feel is necessary for the long-term is good from the start. Brad Penn and Amsoil, among others, make high-zinc break-in oil. After the first 500 mi. (which should mean the rings have mostly seated and the cam is completely broken in) I'd run a 1,000 mi. change of a good high-zinc conventional (probably something rated SM) or use a zinc additive but not both. __________________ Alex V. ------ 1967 C10 Suburban, 350/NP435, Green/Green, PS, PB, HD cooling, charging, shocks, and springs. 1985 GMC C3500 SRW, Sierra Classic, 454/TH400, white/blue.