VOA of amsoil z rod 10w40.

[Jw95]

Thank you for the explanation. I've not kept up with GM's oil requirements but I know they obviously favor MPG.

Unfortunately the government has been pushing that on every manufacturer. Some Toyota cars for example take a 0w8.

You’re very welcome tho.

 

[ARCOgraphite]

Thank you for the explanation. I've not kept up with GM's oil requirements but I know they obviously favor MPG.

Well, The engine is holding up well and can easily 20 mpg on highway runs. It's the trans that can get touchy with age. Just flushed it and added some FM elixir to it to stop clutch pack juddering.