Mystik® Synthetic Blend 15w-50

[WarWagon]

Dropped this in on the 1993 during the last oil change. The hot summers have let the oil pressure drop ~2 ticks above the red at hot idle. AC on over 110 degrees out. GM was never that good about oil pressure on diesels for whatever reason. Regardless it was low enough to concern me.

The Mystik® Synthetic Blend 15w-50 got the pressure up by 2 ticks on the gauge at hot idle.

Note grounds and high current demand from the HVAC blower, headlights, etc. can affect the gauge reading. Before oil change grounds were addressed as well as new OPS that reads the same.

My 2005 Duramax also drops oil pressure at hot idle with synthetic 5w-40 oil. It has an alarm at 9PSI that hasn't gone off so it is ok... But guess what is in it's future for oil. :agreed:

 

[Will L.]

I know your all over the country, but can you run a straight 50 wt during the summer or do your trips take you place where you need the 15 wt capabity?

Also are you doing sampling on the new stuff to compare to the old?

 

[WarWagon]

Straight 50 is hard to find. May have to look harder. Last sample was high in silicon. We will see how this oil does. The viscosity from the old oil was in line with other better oil pressure samples.

Mainly in AZ now.

 

[Will L.]

River city petroleum? I think they may still carry it, don't know how far away you are.