Looking at Kenworth W900L

A lot can be done to improve mileage on that motor , just look up Mr Haney on this forum.
About the poor aerodynamics of the W900 , nothing much can be done.

 

See if it is possible to get an oil sample. Or have a look at past oil samples if possible. The only thing, as with any other truck, is if it is going to need that overhaul soon. If the rest of the truck is in good shape I would say go for it. The Acert cat can supposedly be re-programmed to be a great engine. I have no first hand experience from Mr. Haney however many members on this forum will point you in his direction. If I had a cat engine I would get him to program it.

When I was a company driver sometimes I had an Acert 2006 pete 379 to drive. It wasn't horrible on fuel, it got in the 6-6.5 neighbourhood pulling reefers. If, later on down the road you decide to, the twin turbo can be reverted back to single turbo, it can be expensive though.

 

Im also looking at the accert c15's. Ive looked into the single turbo converstion and its a little under $10000 installed. Calling Mr Haney is on my to do list.

 

As long as an oil sample doesn't read OVERHAUL NOW, I would give 35 for it. Remember I am from Canada and everything costs more here though. I don't suspect they will have a problem selling it for 35. The paint can wait until later. Has the truck seen winter? Is there any underbody/frame rust? If the truck stayed in the south all the time then you shouldn't have to worry about this. Also check for excessive idle hours on the engine.

If the trailer can serve you well at least for a few years then go for it. Great dane trailers are (in my book) the best on the road.