I have always used Delo400 oil in every thing in my 95 U240 Cat3116, Onan 6.5k Generator, Cooling fans, Power steering. Now harder to get Delo400, What is the difference<br/> Chevron Delo 400 XLE SAE Synblend<br/><br/> Chevron Delo 400 XLE SAE 15W-40<br/><br/>What would you choose?<br/><br/><br/>Pat,