Im looking to buy my first diesel truck and Id like to do some homework first. Im looking for a 3/4 ton 4x4. Will be used for pulling 3-5 times a month, and the rest of the time will be majority city driving. So, which would suit my needs best; ford, chevy, or dodge?
Thanks!  

i of course suggest chevy what are you going to be pulling  

Pulling a cattle trailor. Im not concerned with the ability to pull it, b/c I know all 3 can do it just fine. More concerned with MPG, durability(especially with the tranny), and horsepower, especially at the low RPMs. The diesel vehicles Ive driven have had a problem with that.
Also, Im probably looking to buy a pre-owned. The new ones are outta my price range. Any models I should steer clear of?  

Penrod:
Pulling a cattle trailor. Im not concerned with the ability to pull it, b/c I know all 3 can do it just fine. More concerned with MPG, durability(especially with the tranny), and horsepower, especially at the low RPMs. The diesel vehicles Ive driven have had a problem with that.
Also, Im probably looking to buy a pre-owned. The new ones are outta my price range. Any models I should steer clear of?

I'd probably go for a slightly used Cummins. At 100k miles, they're barely broken in, and they tend to be fairly fuel-efficient. Only thing is some of them have tranny problems.

MODELS TO AVOID
I would definitely stay away from the '03 and '04 6.0L Ford Powerstrokes. '05-'07 were a little better, but I still don't know if I'd recommend them. Also, if you're leaning toward a Duramax, get an LLY or LBZ. I believe LLYs were '04 and newer, and the LBZ came out in '06. The early LB7 Duramaxes had some issues with the injectors leaking into the oil supply.  

well if your looking for low end power first choice is cummins and even with some towing and city driving id say ditch an auto for a hand shaker lol  

Ive noticed alot of 06 Cummins on the market. Is there a particular reason so many of these have been traded in?  

Ok, Ive decided on the cummins. Now, any models to avoid? Ive noticed alot of 06's on the market. Looking at an '03 and an '05. Any advice is greatly appreciated.  

people may have traded the 06 ones in for the new 6.7s but i dont know  

that and dodge made a ton of trucks and couldnt sell them so most of the ones that ive seen on the lots have been leased vehicles.  If it were me, id get an 06 quad cab long bed with a 6 speed manual or if you dont like manuals, get an automatic. the new 48RE is way better then the 47re, the thing with the dodge auto is to keep the fluid changed at or before manufacturers reccomended intervals.  the common rail Cummins powered dodge are pretty wicked and tow very well, lots of power low down.  The only model of cummins id steer clear of is the new 6.7, simply because of the emissions stuff, which kills fuel economy and power.  Really, anything in that 03-06 range would be the thing to buy right now, i know where there several for sale for less then 18k.  

The 2003-early 2004 Dodges could be had with the H.O. (high output) Cummins (305hp / 555 lb-ft) and are generally known as about the most fuel efficient Cummins you can buy. They were available with the NV-5600 6-speed manual trans (nearly un-breakable)or the 48RE automatic, a pretty respectable trans stock if you don't get too power crazy (+60-75hp max). After 2004.5, they went to the Cummins "600" (and later the "610"), the numbers referring to the torque rating. There were rated at 325hp, but also had some emissions programming in the ECM and catalytic converters. The H.O. engines had non of this.

To identify which engine is in a particular truck, look on the drivers side of the black valve cover on the top of the engine. There is a tech sticker that will display the hp rating of the engine. 245-250 hp is the S.O. (standard output-only available with 5-speed manual or 47re automatic trans), 305hp is the H.O. engine, 325hp is the Cummins 600 or 610 which started in 2005.  

So, '06 and older, and with a 5.9L?  

To be honest no matter which brand you buy you might want to think about brand new rather than used.  My reasoning is the fact that they are offering such huge discounts now on new trucks including diesels.  Any one have a differing opinion on this?  

From what Ive been told, with all the new environmental additions, a low mileage older model is better than a new one. Besides, financially, I dont think I can afford 30K for a new truck right now.  

One of the biggest draw backs of buying new is the fact they all get crap for fuel mileage when compared to the same trucks before the EPA emissions garbage showed up in 2007.5. My truck averages 22 mpg. Go and buy a new Dodge, Chevy/GMC or Ford and you'll be doing cartwheels if you can muster 14mpg out of them. Ain't nothing like paying $8000.00 extra for the engine and $1 more per gallon for fuel to get the fuel economy of an old big-block gasser.  

Penrod:
From what Ive been told, with all the new environmental additions, a low mileage older model is better than a new one. Besides, financially, I dont think I can afford 30K for a new truck right now.

Wise choice, especially if you plan on doing any performance mods.