My father-in-law has once again bought a new truck. He bought the big 1 ton dodge dually with the big cummings diesel engine. It is a 2008 model. He was told it would get 18 - 20 MPG. He has been getting 10 - 12 mpg. He called the dealer and they told him it was common... they said he would need to get 20,000 - 30,000 miles on the truck before the motor got broke in and the "good Milage" started. My father-in-law is a good honest man, is he being told the truth or is he being taken on this matter? He trades trucks every other year... he puts on 8 - 10 thousand miles a year... is he tradeing to soon? He has been driving the 1 ton dodge trucks for around 10 years now. The dealer told him that he always trades about the time the truck is getting broke in, does this sound right? Also they told him that he couldn't put a different air cleaner on the truck because it would ruin the turbo charger.
Any help would be great.
Mike

The gas mileage he gets is basically the same throughout the truck's life. Maybe a tad better after some mileage on the truck but if this particular truck can get 18-20MPG I'm halucinating. With such a big engine hauling around a heavy truck who does the dealer think they are kidding? Dealers are just that - dealers. Can they actually show him a for real owner of this particular model who actually gets decent mileage after owning it for 30K miles? Probably not. If your dad wants to trade it in every other year - that's his prerogative.

I hear that what he is getting is about average give or take 2 MPG. My Step Father had the gas version and got 8-10 MPG.

In my opinion I believe that fiscally he would be better off keeping the truck 3-4 years before trading it in. If he follows the maintenance schedule, with 30K-40K the truck should be still running like new. New vehicles have their biggest depreciation the first year, to compensate for that you keep the vehicle a year or 2 longer and the total cost of ownership over the long haul decreases.