Interesting info on oil Viscosity for a Supercharged Vett.


Viscosity Grade

Notice: DO NOT use other viscosity grade oils such as SAE 10W-30, 10W-40, or 20W-50.

Z51 Performance Package vehicles utilize the dry sump oil system. This vehicle will come with factory fill 5W-30 dexos1™ oil and an oil fill cap identifying that 5W-30 dexos1™ oil is recommended to top off the engine or for an oil change.
SAE 5W-30 is the best viscosity grade for the vehicle.
For cold temperature operation, where the temperature is colder than −20°F (−29°C), SAE 0W-30 may be used.
For track events or competitive driving, Mobil 1™ 15W-50 engine oil must be used.
Refer to this General Motors website for dexos1™ information about the different licensed brands that are currently available: http://www.gmdexos.com

+1

I don't see how you could go wrong with a Slick 50/ZMax/Lucas Oil Stabilizer blend added to TropArtic 10W40...

Can you imagine where this would go if we talked about what to run in our lawn tractors?! :gfight:

Our Gen IV Viper uses 0-40WT Mobil1.....

I still would like to know, how much better a 10w40 flows, at 75 degree sump temp, than a 15w40. Or a 15w50. I know it will flow better on a cold winter night in northern Minnesota, but what about when its 90* out?

Does anyone have that data? I personally havent seen that testing done

keep in mind that mercury marine reccomend,s their 25w40 oil for most of their engines.

Interesting read....I have pretty much made my mind up on what oil I am going to run on my 496.

Which oil filter should I run? Or is that a whole other can of worms?

First boat I have owned, and have been reading up on oil threads pretty much daily for the past week or so...

I can tell what filter NOT to run, and thats a FRAM.

You can't go wrong with a NAPA gold or Wix equivalent filter.

I have been in these threads before and it seems pointless as everybody has their own thoughts on the matter. With that said the info thrown out in these threads can easily be misleading including the GM/ Dexos1 information. GM hasn't said this oil or that oil is the best. What they have said is 5-30 Dexos1 is the factory fill. Current API AN/Dexos1 specs have a much reduced zinc content. That reduction is fine and will work with these OEM engines. However, in any performance engine being pushed whether or not in a car or a boat, I for one want a better zinc content. A racing oil or a high performance street oil (some European viscosity still has an API rating of SM which has plenty of zinc) is going to be a better choice.