I now have 2800 miles on my 04 HO auto 4/2 quad. at what mileage can I take advantage of synthetic blend or full synthetic.

 

[quote author=petey link=board=20;threadid=21376;start=0#msg200498 date=1066947175]
I now have 2800 miles on my 04 HO auto 4/2 quad. at what mileage can I take advantage of synthetic blend or full synthetic.
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Most of the experts around here seem to agree that 15-20K miles is the ideal time. The engine needs some time to properly break in. I'm sure there will be others who will chime in with some advice. Personally I use regular dino oil - Shell Rotella T 15w40. It's cheap and gets the job done well.

 

I switched to AMSOIL during the first oil change @3750 for the SO (CAL) CTD. I haven't looked back since and I didn't worry about the breakin period because I run it hard and put plenty of miles on it towing at highway speeds. I currently have 19200 miles on it and she just purs down the road when loaded down, actually it runs much better then ;D.
I would go for it and don't worry about it.

 

Look at #23: http://www.cummins.com/na/pages/en/p.../faq/index.cfm

 

Synthetic is much too slick to switch before the recommended interval. NOT recommended until the 20000 mile mark.