Engine FLush Necessary?

[roperteacher]

GOing to be switching to AMSOIL 15/40 Synthetic on next oil change ( Approx 10,000 miles on the ODO). . Will I need to do a flush or just let the dyno oil drain all the way out? I also heard AMSOIL is discontinuing the 15/40 Synthetic and only going to recommend the 5/30??? THanks!

 

[SDunkle600]

Roperteacher,

I would say you should be fine just switching over with no need to flush since you have only 10K on the clock. I have read a lot where Cummins recommends 20K before switching to synthetic otherwise it can prolong the break-in period. I know others on here have switched long before that so maybe they will chime in. I think as long as you have put some miles on towing you should be fine though.

 

[roperteacher]

Thanks!! Yep, she has towed heavy almost every weekend since new... Thanks for the input!!! And I heard from AMSOIL... they are NOT discontinuing the 15/40!!

 

[mberry]

You'll be just fine. No need to flush the engine. I can't imagine they are going to discontinue the 15-40.

 

[6speed]

I have an 04 with 105k think I would have a problem changing to synthetic.