Mixing Delvac 1240 and Exxon XD3 2 cycle oils

[arimkus]

I've been using Delvac (Mobil) 1240 (6V92s) oil for five years and it is now becoming a problem to purchase it but it is available. Has anyone mixed XD3 with Delvac or using it in the DDA's? Any info will greatly be appreciated.

Al

[Paul45c]

Al, if I were you I'd do what I had to do to find your old oil at least until oil change time and then go with one of the readily available oils like Rotella T or something.

[ThirdHatt]

Al, I agree with Paul. I wouldn't mix different brands even of the same weight in one engine. I used strictly Mobil Delvac 1240 for many, many years in my 36C and 41TC because it was the exact same oil that Detroit Diesel rebadged and sold as their own. It had gotten hard to find about 2 yrs ago and I switched to Shell Rotella T due to availability. It still has the low sulfated ash content which is what is really important in these old two-stroke Detroits. I get mine from a local fuel/oil wholesale supplier for $37/5-gal pail. If you have enough Delvac for one engine, swap the other to Rotella (or Exxon) first, then next oil change both will be same again. Hope this helps!

[Paul45c]

NAPA is pretty $$$ competitive on 5 gal buckets of Rotella T, too.

[SKYCHENEY]

Since the Exxon/Mobil merger some of the old oils have been discontinued. Call your local Mobil rep at the distributor. You may find that the XD3 is a direct replacement for the old Mobil oil (ie same exact stuff). The XD3 is a great oil for Detroits. It has the lowest sulfated ash content that I have found (lower than Rotella). I would not be afraid to switch and the availability is not a problem. I would, however find out if the old Mobil is the same before mixing them.