what kind of oil in motor ?

Rotella always seems to have a stinky smell to it .i normally ran 15-40 delo. It's kind of like Chevy... Ford.. What ever you like. I've heard so so things on Mobil . And never ran synthetic.. So I can't tell you if it's better or not. It is cheaper to buy your own filters . Not at the truck stop. Now you know why some call it a **** stop. Fleet guard is rated best, then Wix. All the others are just ok .. Depends on how much you want your engine to last. Also on your primary fuel filter.. The factory will only snug the valve at the bottom of the filter.. Hand tighten it you should get about another 3/4 turn or so. Then it won't suck air and will get better fuel economy. Also if you can afford it get a oil sample. Make sure the guy doesn't get outside contaminates in it. That way you have a running record of what wear , or if there is a problem ready to happen, before it does.. Best of luck