15w 40 oil for a 91 S4

tubejoe · Nov 11, 2009

The owners manual lists 10w 40. Is 15w 40, a suitable oil to use in this model year. I use rotella in my diesels and would like to use it in the spider. I know that people who use 20w 50 in the summers have used 15w 40 as a winter oil. I live in a hot climate, Texas, although it is pretty mild this time of the year. I did search and read most all the oil threads but I did not see this question specifically answered.

Regards

Gubi · Nov 11, 2009

I won't restart the many discussions on optimal oil weight here. But if you want to use a 40wt, there's really no significant difference between a 10W40 and a 15W40 if you live someplace temperate.

ghnl · Nov 12, 2009

I use 15w-40 diesel engine oils in my older cars (Alfa & MG) & motorcycle. They are supposed to have higher levels of the zinc additives these engines need. Be wary (i.e. don't use) oils with 'energy conserving' on the labels. They are usually the lighter weight oils but also have reduced levels of the zinc additives to reduce catalytic converter contamination.

tubejoe · Nov 12, 2009

Yeah,

I'm not interested in starting another oil debate, there is plenty of material to read already. I simply did not see the answer to my specific question. Based on my readings, zinc does not seem to be a issue with a 91 as it does with the cars up to 1980's vintage.

bcrdukes · Nov 12, 2009

I run a 20W50 in my 89 BMW 325i (M20B25 - 6 cylinder SOHC) Works well as it doesn't leak, whereas 10W30 did. Lots of it too.

15w 40 oil for a 91 S4

Our Vendors

Top Contributors this Month

Recommended Communities