New engines or engine components generate high wear metals to begin with and generally contain debris from machining and assembly. It is more beneficial to allow these wear metals to collect in an inexpensive motor oil than to circulate throughout the crankcase for extended periods in a synthetic motor oil. By operating the vehicle to its first drain interval with a petroleum oil, these wear metals and manufacturing debris collect in the oil and are then flushed out of the crankcase when drained. This allows for a much cleaner operating environment for the synthetic lubricant.
quote:Well, although I am a big Amosil user I personally believe Redline makes a better gear oil with more variety of weights in the GL-4 grade. In my experience the RedLine MT-90 or the MTL or their 50-50 mix of MT-90 and MTL will make those gears shift like soft butter, it did for me. I tried the Amsoil first but still have cold shift issues. However, i would hold off for a while before switching, at least 5-10,000 miles to let all the shavings etc. get removed and floating around before draining. Now, engine, I say first oil change to go to synthetic, 3-7500 miles
Originally posted by red2rebel: I have an '03 Dakota 4.7 with 5 speed manual,that currently has 300 miles on it (brand new). I've been told that AMSOIL in my transmission would improve shifting (and hopefully mileage) but am concerned about proper break-in times for both engine and transmission. Can you enlighten me as to best practice here?