Copperhead
Veteran Member
I have had great results with Amsoil synthetic in my Jeep Liberty Diesel. My Cummins ISX hated the stuff. Could not get steady wear numbers using it. When I put the ISX on Mystik Jt-8 synblend, it really settled down and gave good numbers. My current Detroit Diesel is giving great numbers with Delo synthetic and has also gotten similar numbers with standard Delo. This similarity in analysis numbers is why I will use the synthetic Delo in the winter to offset extremes in cold starts (plus I can get it at $19.98 a gallon at my local Wally World), and I use the conventional Delo oil in the summer months. My CUT is showing good results with Schaeffer. I use Mobil synthetics in the gearbox and diffs on the semi. On my previous semi, I used a top notch synthetic in drivetrain that was a local distributor brand label. I just can't seem to find a one size, fits all brand of oil that turns in great results in every piece of equipment I own. Never have.
For my semi, oil changes are never done below 30,000 miles. CUT gets an oil change each Fall. The Jeep goes 10,000 between oil changes. I have taken one semi to 1.4 million miles, doing 30,000 mile oil changes using Kendall conventional 15w40, and never had to open up the engine for a major repair. Took my last semi to almost 1 mil doing the same thing with Mystik synblend oil before I sold it. Still did not have to open it up for a major engine repair. The 2013 semi I have now, too new to see how it does. It only has 72,000 miles on it so far. Out of all the trucks I have owned or driven in over 3 decades in trucking, only have lost 1 turbo in all that time. So, I have had good/bad results with synthetics and the same with conventional oils. Brand loyalty means nothing to me. I long since quit falling for that marketing game. The Jeep now has 104,000 on it, and the UOA's look as good as when the engine had 20,000 on it.
For my semi, oil changes are never done below 30,000 miles. CUT gets an oil change each Fall. The Jeep goes 10,000 between oil changes. I have taken one semi to 1.4 million miles, doing 30,000 mile oil changes using Kendall conventional 15w40, and never had to open up the engine for a major repair. Took my last semi to almost 1 mil doing the same thing with Mystik synblend oil before I sold it. Still did not have to open it up for a major engine repair. The 2013 semi I have now, too new to see how it does. It only has 72,000 miles on it so far. Out of all the trucks I have owned or driven in over 3 decades in trucking, only have lost 1 turbo in all that time. So, I have had good/bad results with synthetics and the same with conventional oils. Brand loyalty means nothing to me. I long since quit falling for that marketing game. The Jeep now has 104,000 on it, and the UOA's look as good as when the engine had 20,000 on it.
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