Is it worth getting a lower stall torque converter? What will that do to MPG, driveablility, and towing? Where would you find one??

 

ATS,-- or BD. Several co make good torque converters . ATS will set your stall speed up according to HP-Tor. specks of motor. RPM wont wind up so much for the speed your going on takeoff. But once the torque converter locks up,then theres no difference from stock. You have 45 square inches of torque converter clutch surface on stock ,ATS converter gives you 119 square inches. Its called tripple lock , much stronger. ATS tripple lock cost $1800.00 plus instalation, must pull trans out to install. NOT CHEAP. Any improvement in fuel mileage would be gained only from less slippage on takeoff . No gain after torque converter lockup. So mileage gain would be vary marginal. But you probably would like the improved funtion on takeoff.
Your new truck has the much improved 48re over the older 47re in the 03s. My advice is drive what you got, see how you like it. A not needed upgraded torque converter is quit pricey going in a new truck.
Also the 05 48re trans dropped the 4th gear lockout feature, which was in all the previous years and was reinstalled in the 06 48re. This lack of 4th gear lockout would be much more concern to me than a better torque converter. ATS can fix the 4th lockout for a price. So if you pulled the trans for a torque converter you could fix 4th lockout at the same time . Just my $.02

 

I just had a Goerend single-disk TC installed last week.

Is it worth it ? Well, if, like me, you can't stand seeing the tach go up to 2000+rpm's at 30mph up a 2% grade unloaded when you got 600 ft-lb of torque at 1600, then yeah, it's worth it.
I used to drive in T/H all the time, and try to get the tranny to upshift to 3rd locked asap so I could feel the rear wheels actually connected to the engine.

I can now go from 0 to 60mph without going over 2k rpm, as quick as before when going well over 2500. I can cruise at 25-40mph, 1000-1400rpm, in OD unlocked, up and down back roads without the tach going up to 2k+ at the slightest hill like before.

When you mash the go pedal, the engine revs to about 1800 and starts pulling hard. The rpm's actually drop during 1-2,2-3,3-4 shifts now, from 3000 to 2100 at full throttle.
During lockup, the tach only drops less than 200 rpm's.
I didn't do anything to the VB and the computer controlled tranny adjusted just fine (no throttle cable adjustment on 05's).
The tigther TC actually got rid of the 1-2 gear hunting at slow speeds since now it pulls just fine in 2nd and doesn't have to downshift to 1st to get moving.

All in all, it almost feels like driving a standard (except a lot quicker off the line ). Awesome !!

I can't comment on mileage yet, but since it takes less rpm to get moving, in-town mileage should be a tad better.
Oh yeah, I forgot to mention that I installed the Rokktech sensor 2 weeks ago, which improved the low end response of the engine. The better low end+lower stall TC makes for a great combo.

If you want more info from a very good tranny guy, call Goerend Brothers http://gbtransmissions.com/. Dave spent a lot of time on the phone going over how a TC works and everything. A lot of 2nd gen guys use his TC's/Tranny's.
Tell him what you're planning on doing with the truck and he'll hook you up with something sweet for a very competitive price.
I'd also call the other vendors out there to get their opinions, so you can make an informed decision.