Interesting oil and rod bearing discussions
 

The following links have some great information on oil viscosities and their impact on bearings:

http://www.bobistheoilguy.com/forums...2477193&page=1
http://www.bobistheoilguy.com/forums...ue#Post2448328

Basically, we want an HTHS of at least 3.5 but need to be careful not to use an oil that is too thick at operating temperatures or the oil pressure will get too high and the rings won't get as well lubricated.

Re: Interesting oil and rod bearing discussions
 

For those of you that are fans of Valvoline Maxlife FULL Synthetic, Amazon is offering a 15% discount if you get regularly scheduled deliveries of the 6 pack. The price of the 6 pack is $39.33 with free delivery:

http://www.amazon.com/Valvoline-VV17...pr_product_top

This oil has good low temp performance for those of us in the cold and the latest HTHS I found was 3.5 so that is good too. I haven't been able to find numbers on the amount of Moly, Zinc and Magnesium. I think M1 HM 5W30 is cheaper at Walmart but it has a slightly lower HTHS of 3.3, which is still pretty darn good for a 5W30. The M1 supposedly has a slightly higher TBN so it should last a little longer.

The best 5W30 dino oil I have been able to find in terms of HTHS is the Quaker State HM. It has an HTHS of 3.4. Basically, any of these oils will be as good, if not better, than most 10W30 oils for our car but give you the winter viscosity one needs in the North.

Some people have said that they like the Rotella T6 5W40. That oil has a very good HTHS of 4 and a very high TBN of 11.5 so it should be good for our bearings and last a very long time for extended OCIs. However, it is quite thick at operating temperature and that concerns me a little. Also, it has an astronomically high concentration of Magnesium. Mg acts as a detergent and dispersant but it can also be corrosive to the metal parts in the engine.

Another option mentioned earlier is M1 0W40. This oil has a very good HTHS of 3.8 and a very high TBN of 11.8. It isn't quite as thick as the Rotella at operating temperatures so it should flow a littler better. And it doesn't have a very high concentration of Mg. If one adds Lubegard Engine Oil Protectant to either the M1 0W40 or the Rotella T6 one would also get the seal conditioners of a HM oil plus an added ester which helps protect the engine at startup.

Just sharing new information as I get it..........