Extended oil drains

[Pete1990]

(07-19-2020 )Mattman Wrote:  Just a note on the gear oil. I have an emission friendly truck. Everything is intact and working great. I add one gallon of 80/90 gear oil when I change oil. I change every 15,000. Been doing this for six oil changes. Hasn't hurt mine yet to my knowledge. I go the 15,000 and don't have to add any oil between changes.

Going to keep doing it to mine. I have thought 25,000 miles on oil changes would be nice, but oil and filter is cheap. Camshaft and rockers not cheap. Makes me sleep well at night at least.

The sulfur may hurt the dpf so in the long run you might be doing damage to the doc n dpf.