7.5 Onan Diesel Generator

[Onthroad]

What is the best oil to use in a 7.5 Onan diesel generator (excluding the over priced Onan brand)? Is it okay to use Rotella-T heavy duty SAE 15W-40, the same oil we use in our Discovery 39L with the 330 hp Cat. engine? Thanks in advance for you response.

[Onthroad]

What is the best oil to use in a 7.5 Onan diesel generator (excluding the over priced Onan brand)? Is it okay to use Rotella-T heavy duty SAE 15W-40, the same oil we use in our Discovery 39L with the 330 hp Cat. engine? Thanks in advance for you response.

[BZam]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Onthroad:
What is the best oil to use in a 7.5 Onan diesel generator (excluding the over priced Onan brand)? Is it okay to use Rotella-T heavy duty SAE 15W-40, the same oil we use in our Discovery 39L with the 330 hp Cat. engine? Thanks in advance for you response. </div></BLOCKQUOTE>

I asked the Onan Rep and he told me to put exactly what I put in my CAT engine and it would be fine. He said its a diesel so use the same.

[Gary RVRoamer]

Your Onan manual will tell you the answer: for the temperature ranges that RVs expereince, use any 15W40 oil meeting the Diesel CG-4 API specification.

[Onthroad]

Thanks you all for the replies! I did read the manual and Rotella complies with the SAE and the CG-4 requirements, but when the Rotella label read "For Heavy Duty Engines" I just wanted other RV's input. This makes it easy, I only have to carry one type of oil on the road for keeping both topped off to the full mark.
Thanks Again,

Larry & Darlene