Best older high mileage truck/engine combinations?

What I am wondering from all of your experiences what is a better higher mileage engine and truck? I know everyone will have varying opinions and I welcome them all. The kind of information I'm looking for is things like reliability, costs of repair ( which motors cost more and which ones cost less typically ), which older trucks tend to hold up better with high miles, etc..... and those sort of things. I'm thinking of spending in the $10k neighborhood because the way I figure it I could spend up to $20k but still have a high mile truck so why not find a decent truck for $10k and keep the other $10k just for big repairs in case a motor goes or something else. This $10k will be put back on top of money I have put back for reserves already. I'm not looking for a LOOKER ( obviously) but a money maker. I was going to do a poll but to many choices of combination's to list. Thanks for your opinions.

 

Yep just realized I left that part out.

Gonna be leasing on to a local company here that I'll be running around IN,KY,IL,OH,MI and they have no age restrictions as long as it passes DOT inspection. Pulling dry box freight.

 

WOW only 1 opinion out of 37 views so far.

 

Thanks for the info skeezix. This is exactly the kind of info I am looking for. I have never run a detroit and I know they are quite common in the older trucks especially the Freightshakers. I have pretty much ran cummins for the most part and a few cats. Yeah I don't idle unless it's pretty warm or really cold. I don't un fast anymore either because I hate giving uncle sam anymore money then he already gets in taxes. No I'm not thinking of Horizon have not even looked at them. Who are you leased with or do you have your own authority? Thanks again for the info.