Something like this would seat your family and some friends.
Used 2003 Ford Excursion XLT for Sale by Oyster Point Motor Cars

 

I didn't even think about an excursion, if you don't need a bed then an excursion would be my choice for sure. Tons of space inside and a roof rack. One of the outfitters I hunt with has his wife in one and with a superchips programmer gets 20mpg on the highway. It's the ole 7.3 though so it would be an 02 or older.

 

Somebody mentioned the 6.4 being a good option. My 08 f450 with 6.4 averages 8 mpg and weighs about 12k. It has 65,000 miles and had egr cooler issue, two radiators and the water pump plate was eaten thru and filled the crankcase with coolant. This was taken care of under warranty but I am sure that this thing is going to have more issues related to that one. Ford says lack of cooling system maintenence is the cause!

 

I have no idea why Chevy doesn't make a diesel Suburban anymore. I was told that you can order a diesel suburban from the factory but I can't imagine what a 2012 Suburban diesel would cost. More than my house probably.
I just can't get past the looks of the Ford or the Dodge. I just dont like them. It sounds like the Duramax has it's own line of issues unless you leave it mostly stock. I'm ok with that. Just a good tune and I'd be willing to do a converter if it needed it. I plan to leave the suspension alone.

Do all Duramax trucks come with the 6sp-Allison or is that an option?

 

All the Automatics use the Allison 6 speed auto. I believe there are some 6 speed manual transmissions out there, if that's what you want.

 

Automatic is what I want for sure.

 

06 and up have the 6 speed Allison. 01-05 have the 5 speed.

Its about 200 lowercruise rpm difference in RPM from the 5 to the 6 speed.

And the 6 speed is stronger from the factory. Add a transgo jr shift kit and it really helps hold more power, and the kit is only around like 100$ IIRC.

My truck has been tuned since about 500 miles. Not one issue and i drive all the time on my race tune ( around 500 rwhp) . Its like anything else, i drive hard but dont beat it to death and change my fluids often.

 

Is this why there are 985 sets of bosch LBZ injectors on backorder?
If you live in a area that is a cooler climent with not many long 6% + grades and 5000'+ altitude you prob know nothing about it. There are many trucks with defective injectors that just never meet the conditions to set the P0087 code but give it time and they will... I've seen the problem as early as 70K miles, and as late as 500K. If the truck has had fuel additive run a good part of it's life they usually fend a lot better.

Your 04.5~05LLY Is your best bet for gambling with a high milage Dmax. Other than some over heating issues when towing really heavy in extreme heat, and some EGR issues I have seen very few problems with them. I just picked up a 125K 05LLY for my dad ExLB 4x4 clean truck for $11,500. I added a 90HP PPE, and blocked the egr and it's a great running truck.

 

I like this. Its a lilttle pricey but, low mileage
GMC : Sierra 2500 - eBay (item 300598426566 end time Sep-18-11 05:29:32 PDT)

Chevrolet : Silverado 2500 - eBay (item 140604753867 end time Oct-01-11 08:22:13 PDT)

Chevrolet : Silverado 2500 - eBay (item 260851757056 end time Oct-01-11 14:12:33 PDT)

 

FWIW I paid 26otd for my 06 lbz fully loaded with 73k in January of 08 so those aren't very good prices imo. These trucks are 3 years older and for what you want if you look hard enough you can find one for 20. Check autotrader too, that's where I found mine.