These articles are long but very interesting as well as useful. These may not contain absolutely everything about the topic at hand but it is far more than most people will ever know...

Dr. Ali E. Haas - Oil
http://www.ferrarichat.com/forum/faq...=haas_articles

Russ W. Kinze - Filters
http://minimopar.knizefamily.net/oilfilters/index.html

Kit Sullivan - Oil
http://www.boss302.com/oil.htm

 

Well, what do you guys think?

 

I learned quite a bit from these articles. The content cast a shadow of doubt for users who have converted to 5w30 on the S197 .
Thanks for posting

 

Why do you say that? That was a lot of information I just read so I'm still not sure I understand it all, lol, but are you saying that some people with GT's (which calls for 5W-20) have filled up with 5W-30? The V6 calls for 5W-30, but the GT calls for 5W-20. Why would they fill up with something thicker?

 

There are a few posters who swear that 5w30 and 10w30 etc. are the way to go for the S197 4.6 GT I don't understand why anyone would move to a higher viscosity oil unless they operate the engine at elevated oil temperatures . IE road racing.

I would love to see some dyno results where someone changed the oil weight to see the impact on horsepower. I read where Kenne Bell did some testing and suggested Redline then Mobil 1 but did not say what weight they used

 

I don't understand either. After everything I just read, my understanding is that, unless you need the higher viscosity, don't use it. You're pretty much just doing more harm than good if you do by making your engine (and other parts) work a lot harder when it doesn't have to. You're also hurting your MPG's.

 

I would run 0w-20 if Amsoil offered it. Since they do not, I use their Signature Series 0w-30 and feel great about it especially after seeing Mr. Haas' observations.

 

They do offer 0W-20 - http://www.amsoil.com/a/synthetic-motor-oil-engine-oil
second one on the list

 

I'll be damned, never noticed it! Thanks for the heads up.

 

I actually just changed my oil and used Amsoil 0W-20 with a FRPP oil filter.