2 things......

The allison is not the strongest stock auto tranny out there. If you start throwing 100+hp tunes on a Dmax (sometimes less), the tranny will most likely start slipping, which if it is bad enough, can throw it into limp mode. And I've even heard stories of 80-90hp tunes doing it, just depends on how hard of a driver you are. Don't get me wrong, with a few upgrades, the Allison can be one heck of a tranny for the performance world but if you put enough money in any transmission it'll hold the power

The strongest tranny out there right now IMO, is the 5R110 Torqshift. I hear quite often of Dodge and GM trannies going out, but I have never personally heard of a Torqshift having problems (although I'm sure it does).

There are 6.4's running 210 and 250 Spartan tunes every day, with not a hiccup out of the transmission, and I have even seen 275 and 310 tunes ran consistently. Those are all rear wheel gains. There was a 6.4 featured in Diesel Power running a 310 tune and nitrous, putting down a little over 700 to the wheels, and the tranny was holding it. I'm sure it wouldn't last very long with that setup ran every day, but it was doing it.

Now if only Ford could get a bulletproof engine in front of that tranny

 

hey ford had a bulletproof diesel, the 7.3. I see you are willing to get behind 03, which is when they stopped making the 7.3. That would be my recomendation. 7.3s are unstoppable, with proper maintance they will last forever. No trucks where good after the last 5.9 rolled off the line (06?)
so, all in all, i would say GET A 7.3! If you are worried about power, there are tons of mods you can do. and they are goin cheap here in the louisville area, just saw an 02 f250 reg cab with 130,000 go for 3000

 

I would go with the cummins 5.9 over the iszuz 6.6 duramax

 

Id go Dmax, had the others, no comparison with a good tune. They ride really good too.

 

hey kuntry no to hijack but what happened to your 03?

 

Short in the wiring harness burned the interior up. It was a sad sad day.

 

wow man. If my dads truck caught fire, I think I might shed a tear.
It wouldnt bother me if my girlfriend caught on fire.
isnt it funny how that works?

 

Cause it's alot easier to get a girlfriend, than a nice diesel truck

 

the truck never nags about me putting my stick in gear

 

and it's way easier to get a girlfriend than a duramax with a zf-6 that's for sure, but this is a funny thread, the 7.3 is far from bulletproof, there isn't a bullet proof engine out there, especially not an international 7.3, until the 6.4 internationals were way expensive to build up to anywhere near the levels you could achieve with a Cummins or Duramax for less than 1/2 the investment, Dodge has automatic trans issues, Allison is great with simple upgrades, the 5R110 from ford probably is the best trans out of the box, drive em all and decide what you like, when looking in the used market though it's hard to compare trucks cause you never know how the previous owner treated his stuff