Join Date: Jul 2002
Location: Clarksville Tn.
5w-30 is only good for a new engine. Ford uses it to get the highest possible mileage in the EPA test. All Ford Engineers cringe at this. It would be fine at -10 degrees, where higher numbers would not flow
as well at start up.
My old 5.0 had 180,000 miles on it, and still ran fine. I used 10w-30 year around until it got over 125,000 miles on it, then since the clearances were larger, went from 10w-30 year round, to 10w-30 in the Winter, and 20W-50 in the Summer. I live in Tennessee, and the daily 90+ in the Summer is not conducive to long engine life with the lower protection you would get from 10W-30 with aggressive driving.
The only reason I am not running the 5.0 now, is I wanted a BIG HP increase, and 180,000 is a little late for doing that. I have never needed to add any oil between 3,000 mile oil changes. I did a compression test on the engine, and it was still within 10% of specs. I did this with a guy that wants to buy my old engine and trans.
-----1993 Bird 5.0------
393 stroker, Vortech YSi, on E85
Lentech Strip Terminator & 4,000+ RPM stall converter
Detroit Locker with 3.55 gears.
17x9 Cobra Rs with 255/45/17 BFG KWDS
275/50/17 M&H DR on the rear
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