When I converted my pickup over to 5-50 castrol I needed two oil changes in two months...
Now I run 9K per change with a new filter and requisite quart to fill the filter every 3K.
I have not yet converted teh 300DT over to synthetic, that's teh plan though.
-nB

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'83 300D Turbo
Current: ???K mi - 19.2mpg -> 17.4mpg -> 22.9mpg ---> ODO Died
bought at: 233.8K mi - 10MPG For $1.00
3.5 cylinders work: 320 320 100 340 280
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