Whats the best handheld value for 2006 LLY?

[Mark Rinker]

Interested in comments from those that have modified tire size on 2006 LLY/LBZ and used a handheld power programmer to keep speedo calibration accurate.

What is best value in programmers? Who has best tow/economy tune?

[More Power]

I spoke with a guy yesterday who is quite happy with his Hypertech, which does stress improved fuel economy as one of the features for their programmer.

Jim

[mafrazer1]

I acquired an '03 Silverado w/duramax, which had P285 tires.
Watching the odometer on regular trips, some error was noticed.
I took to dealer for some reference service, and asked to calibrate speedometer for P285 tires. Was charged $45 to tell me they can't.
In addition, they claimed they could not perform a front end alignment due to the P285 tires.
Now I really know why some members refer to the "stealer".

[mr. monte]

when I had my 04 gasser w/ 285's, the dealer told me up-front they couldn't set the speedo for them, they could only recalibrate it up to 265's.

they told me; cause 265's are the largest tire GM offered on our trucks, then said my warranty on the drivetrain was void now cause of the 285's this happened when my 04 was only a week old

so now you know why there is still 245's on my LBZ

I have been emailing and calling GMC non-stop, asking them; what is the largest tire diameter tire allowed without voiding my warranty, THEY WILL NOT RESPOND TO MY QUESTION!!!

I told them I want it in writing so I had documentation of this, because every dealer gave me a different answer, and not one would provide it in writing

[Mark Rinker]

No thread hijacking, please. Topic is hand-held programmers for 06 LLY.

[AVEX]

I have just recently bought a Programmer III from Hypertech. I have an 05 D/A. I have noticed considerable performance impovements. However, my fuel mileage is still in the toilet. I don't know why. DIC is close enough to doing it by hand. I am getting 13.7 no matter what mode I am in 1, 2, 3 or stock. Sure is peppier though. I did this to help my milage, oh well. I do like it alot though, but now I am just running bone stock. No sense in running the programmer mode unless I am pulling something. So that is my experience.

[Mark Rinker]

My '05 LLY was the worst on fuel mileage of the five DMax's so far. Thats one of the reasons its no longer in my signature block.

Maybe its just the year and early EGR, cat, variable vane turbo setup...? The '06 LLY (early LBZ) is better, and its a dually!

[6.6Turbo]

check out the predator

[chadc30]

Mark, I have a superchips flashpaq that I used for my 265's. It allows you to measure the tire and input increments down to 1/4 inch. I compared the speed to gps afterwards and it seemed to be right on.

[eric777]

I have an 04 Duramax and I bought the Hypertech III programmer. Gas mileage DECREASE on stage 1 and stage 3 (didn't test stage 2). I am sending it back to crutchfield. I am getting 19mpg stock, so I don't want to go down and I only bought it to see if I could get BETTER mpg. The truck is powerful enough stock for me.

[Mark Rinker]

Sounds like you need to dial in some more boost with the Hypertech. Lots of black smoke on acceleration or when towing?

[Kennedy]

I think Mark already knows which direction he needs to go, but...

As for MPG with fuel prices the way that there are, there are a lot of manufacturers making claims (marketing) of big MPG gains. Some see gains with these devices, but in my experience most don't. I learned a long time ago not to make promises on MPG gains as I can't control this. HP is repeatable, but MPG is more tricky. Most of my Custom tuning customers report best ever MPG gains, but again no promises from me.

[eric777]

Sounds like you need to dial in some more boost with the Hypertech. Lots of black smoke on acceleration or when towing?

There is no way to do that.

[Kennedy]

There is no way to do that.

A good tune will. Actually boost is added in some places and removed in others. The problem is that most of the big name stuff hasn't even touched the boost tables at all.

[eric777]

A good tune will. Actually boost is added in some places and removed in others. The problem is that most of the big name stuff hasn't even touched the boost tables at all.

I don't know what hypertech does with their tuning. I just know it gives you the option for stage 1, 2 or 3. I am sending the unit back anyway.

[bigchev]

I think Mark already knows which direction he needs to go, but...

As for MPG with fuel prices the way that there are, there are a lot of manufacturers making claims (marketing) of big MPG gains. Some see gains with these devices, but in my experience most don't. I learned a long time ago not to make promises on MPG gains as I can't control this. HP is repeatable, but MPG is more tricky. Most of my Custom tuning customers report best ever MPG gains, but again no promises from me.

When I purchased the Kennedy ECM I was looking for reduced turbo lag which I really got! I didn't expect the increase in fuel mileage of approx. 2MPG. Just a little bonus!!