I just bought my Mustang with the 4.6 and the only oil that I am supposed to run in it is 5/20. Doesn't this seem kind of light? what does your manual say to run?

thanks,
dj

 

My dad's 2002 S'crew manual says the same thing. The tighter tolerances in the newer engines call for a lighter oil to fit in the gaps. If you have a warranty, I'd follow the specs until it runs out. We have a couple of threads in this forum that adresses this question in more detail.

-Kerry

 

Thank you for the reply Kerry. I have been looking around for more info in the forum and on the web and not liking what I am finding out.

Thanks again,

dj

 

what's not right about it? it's what Ford engineering recommends. Make sure you use a premium synthic blend when changing your oil as well.

 

why synthetic blend vs. non-synthetic or full synthetic?

 

Dummies, the 5W-20 is how the oil "acts" under certain temps.

ok 5W-20 will have a higher viscosity in low temps compared to:

10W-30

10W is the viscosity cold/30 is viscosity warm(well it translates)

5W-20 creates less crankshaft lag so the engine has slight hp/gas milage increase with lowwer emmisions

 

How does that make us dummies? Because we didn't go into the technical aspects of the oil? Like the 5 weight base oil allows for a higher flowrate under cold weather starts versus the 10 weight or the polymer strings are restricted to expand to the characteristic of a 20 weight and thereby fit into the tighter tolerances allowed by today's machining techniques versus the polymers found in a 10W-30... don't call people dummie They might not like that too much.

-Kerry

 

Sorry about that

 

there was a thread a few months ago stating the primary reason Ford recommends 5w20 is for the slight (something like .2 mpg) gain in mileage. The feds allowed Ford to report the mileage gain for EPA purposes so long as Ford ensured the oil was widely available in the market place (wallyworld,etc). I run 5w20 in my daughter's 2001 mustang for warranty reasons but will switch to 5w30 at 36,000 miles.

 

well that a nother fine mess

go a head and run 5-20 in the winter(if you have one)
5-30 in the summer(ditto)
..........WHEN NEW...............
run it 100 miles change the oil drive easy and buy it at ZERO
MILES
then at 500 miles change the oil
at 1000 mile flush every fluid add the best coolant synthetic brake syn tranny and 5-50(maybe the 0-40 or 50) FULL synthetic oil and the best oil filter avail

stick to the same brand and type as they are different
stock a couple cases of you choice

you can change it at 50 thou under fav conditions alot of city at 30k

and odds are real good you will never need a warr exepts for the tissue paper thin steel rusting out

that is the guide for breaking in your vehickle