Just picked up a 2003 LS 4dr 2500HD with a 6.0L 4l80E. I can feel the torq difference over my 08 Silverado's 5.3L, but it needs more!

What kind of gains will I see with a good healthy custom tune?
Power gains?
Shifting improvements?
MPGs? ( LOL ya right )

Here is a shot of the truck. Its not to bad for 70k miles.

 

Nice truck. I did a live tune with Justin at Blackbear Performance on my 05 2500HD 6.0 a month ago. There is a huge difference in mine now. Mine apparently had a power adder of some sort before the tune with him ( hypertech or similar) but he really woke it up. He firmed up the shifts to how I like and now I get right around 13 mpg in town, up from my 11.5, and 15 or slightly better on the highway.

 

A tune should really wake it up. And especially removing torque management (which with your 4l80e will be a non issue as far as reliability goes).....you're engine loses momentum during the shift and it really makes for shitty driving....I can really feel my engine bogging during during and after the shift, but I'm keeping in 50% Tq management to save the 4l60e until I can get some time to put my 80e in.

 

Thanks for the comments. I have had 3 of my other trucks tuned in the past. All half tons. I know my 79 really woke up the more we refined the tune. I was just curious what you guys with 6.0's are seeing. Sounds like its a no brainer to me. It does shift pretty firm now compared to my 4L60e trucks, but I think that is just the difference in the trans and what it will take. No real lag after shift in comparison.

I'll keep ya posted on what happens after the tune. My tune buddy is on vaca... so I have to be patient!

 

I was in the same boat as you. I bought my new to me 05 Crew K2500 on 35's and the initial torque factor sucked. I worked over the tune and now it is quite a bit better. But I'm wanting more so I bought a KBRacing front mount kit and will start that as soon as my girlfriends 98SS is outta of my garage.

 

looks just like mine... a tune will really wake that up... as far as MPG goes.... its a heavy pig and i thought you'll get over 15mpg....

 

I have an 04 crew cab 4wd on 33s . . and a tune helps out a ton . . . I just started playing with the tow/haul . . . and pulling a 4K boat last night . . . I took out all the TM and abuse modes

 

my old truck i put edelbrock shorty headers on and that made the throttle way more responsive

 

Did you do headers before your exhaust mods? I can only assume you didn't natural progression for most of us is intake/cat back..so on and so forth.