When there was a magazine in print that Teague (Teague on Tech) replied to, he stated all synthetic oils, except AmzOil, made the rollers on the lifters slide on the cam and created flat spots on the rollers which ended up tearing up the cam. I call BS. Who is his sponsor...oh ya. Use synthetic it's awesome. When I used to run conventional oil it would come out black, which meant it was breaking down and not protecting the engine. Now I run synthetic in everything I own, change the oil at longer intervals and it comes out almost the same color.

If you want a true test buy a wix oil analysis kit 24077. You can buy them online or at any parts store that carries Wix, about $20. Try it with the old school oil then try it with synthetic. They give you results which will let you know what metals are found in the oil and where they could be coming from, based on what type metal is found, and if it is not an acceptable amount. They also tell you what the viscosity of the oil is when they test it. I did it with Mobil-1 after 15,000 miles in one of my vehicles. Everything came back great and viscosity was within 2 numbers of when it started.

Oil is suppose to get black. The "black" is the soot, dirt, combustion by products the the oils detergent/dispersant package is holding is suspension to carry these contaminates to the oil filter and get filtered out.

Black by no means the oil has broken down.

I change the oil in my diesel and within 1,000 the oil is jet black. Broken down, I hardly think so.

If you oil isn't getting black from use, it is not doing it's job. Find a different oil.

Ken

You are compairing diesel to gas??? Mobil 1 may not be the best oil out there, but I'm sure it does a good job. Maybe using a good filter, Wix, might also help me.

No expert here but have had good luck running Valoline VR1 Racing Dino oil SAE 40 or SAE 50. Also used Kendal Racing Dino Oil SAE 40 or SAE 50 in my Procharged 500EFI's with ZERO problems. I have nothing against synthetic just can easily get the racing Dino oils locally for less money and I like to change my oil every 20 hours just because. I also run a WIX racing oil filter.

Wish there was a easy way to research and learn about oil but its so confusing and impossible to find answers that are not biased.

That's interesting you run Kendall. There is an engine builder just outside of St. Louis and that is all he uses. I know a couple of guys that used him, he builds some nice reliable stuff.

ALL oil gets black with use, diesel or gas. Diesel just get blacker sooner.

Ken

Brad Penn (bought Kendall oil back in the early 90's) then Joe Gibbs make a dino oil also. Both are some of the best oils produced. Kendall is also a great oil. Swepco 306 oil is also a awesome choice. All of these oils listed have a high zinc content and properties that you need in marine applications.
Most of these oils are about 8 dollars a quart. Better pricing if you buy cases or gallons.

strange,but some oils are more expensive by the gallon...i know amsoil is...

Ive always ran the Valvoline VR-1 in my motors and had no problems, but my new boat has a 500efi in it and was thinking about switching to Royal Purple... kind of a toss up..