I want to correct my speedo and odometer on my 2500HD D/A LLY. I have upsized my tires to 285/70 R17 and my speedo is off by about 6 mph at 65mph. If I buy a Hypertech programer I know I correct the speedo but the question I have is do I have to leave it connected, or do I just plug it in make the correction and then unplug it. I already have the Juice W/Attitude installed and I can get the speed there but I would like to have the speedo correct.

Thanks for your help

can't say that I have a real answer for your question, but some food for thought.:thumbsdow
I had bad luck with the Hypertech on my 03 gasser. fried my computer.
seems everybody on this site is having good luck with the Predator, that is the way i plan to go this time around:think:

you just hook it up, change the tire size, and unhook it. Thats all there is to it.

for what those cost and all you want to do is change the speedo...you might as well just get used to it. Seems a waste of money to me just to do that. Just my opinion of course. Since you arleady have the Edge/*** and can verify speed at any time.

and no, you don't have to keep it connected. it will copy the factory program to the Hypertech, then ask you questions- in your case you just want to change tire size, you answer it, then it writes the program back to the truck computer. It takes like 15 minutes or so for it to copy and write to and from.

good luck with your choice

I've used HyperTech on two gas vehicles, and currently on my 05 Duramax. I've had no problems. It's quick and easy to operate up laoding the information into the vehicle computer in about 15 minutes you unplug and enjoy. I've even lite up the tires at stage 2.
:ro)

Diablo Predator gets you top speed limit increase as well as the ability to read engine data tables. Well worth the extra price. More tunes and better tunes also.

I didn't see where the Hypertech lets you program speedo only on the stock tune either...

Diablo Predator gets you top speed limit increase as well as the ability to read engine data tables. Well worth the extra price. More tunes and better tunes also.

I didn't see where the Hypertech lets you program speedo only on the stock tune either...The Hypertech unit will ask for the tire size if different from stock, and once you input the new size it automaticaly changes the speedo.

I wouldn't be so sure about that. Have you verified this? It would be quite uncommon for the tire part of the programming to be written independently of the tuning.


To add to my earlier comments:

With Predator's the larger backlit screen you can see the prompts much easier, and also operate in the dark.

check it out...
http://www.hypertech.com/tiregear.html

Not really looking for a performance increase, just want my speedo and odometer to read properly. The Edge does a good job with added power, I run in level 1 and have found a 1 mpg increase. With the Hypertech I am just looking to get the computer back in sync with the speed the truck is actually traveling at. I have been told that there are engine adjustments the computer makes on the fly based on the speed being reported to the computer.

As for using the attitude for speed, I still have mixed emotions regarding the Juice. It seems the only time I have problems with my truck is when the Juice is plugged in. I had it on my 03 D/A and it went through 3 full sets of injectors in 10k miles!! Yes no typo 3 sets! GM would not buy it back since I was over 36K miles but they gave me one sweet deal on an 04. The dealer sold the truck to someone else and 1 week later it was in the shop for a 4th set of injectors!!!
Drove my 04 first 15k miles without Juice, put it in and at 20k, Yep injectors again. took it off drove upto 30K no problems, put it back on, truck started bucking and hesitating when cold. I did find the fix for that however.

Sorry I got a little long winded and off topic, thanks for your replies.

Drove my 04 first 15k miles without Juice, put it in and at 20k, Yep injectors again. took it off drove upto 30K no problems, put it back on, truck started bucking and hesitating when cold. I did find the fix for that however


OK, what did you find as the fix??

Not really looking for a performance increase, just want my speedo and odometer to read properly. The Edge does a good job with added power, I run in level 1 and have found a 1 mpg increase. With the Hypertech I am just looking to get the computer back in sync with the speed the truck is actually traveling at. I have been told that there are engine adjustments the computer makes on the fly based on the speed being reported to the computer.

As for using the attitude for speed, I still have mixed emotions regarding the Juice. It seems the only time I have problems with my truck is when the Juice is plugged in. I had it on my 03 D/A and it went through 3 full sets of injectors in 10k miles!! Yes no typo 3 sets! GM would not buy it back since I was over 36K miles but they gave me one sweet deal on an 04. The dealer sold the truck to someone else and 1 week later it was in the shop for a 4th set of injectors!!!
Drove my 04 first 15k miles without Juice, put it in and at 20k, Yep injectors again. took it off drove upto 30K no problems, put it back on, truck started bucking and hesitating when cold. I did find the fix for that however.

Sorry I got a little long winded and off topic, thanks for your replies.

With all of that trouble, I'd just buy a hypertech, put it on level 3 and recalibrate the tire size, and get rid of the juice. (not that I am against the juice myself, I plan on eventually getting one).

You might want to check with your dealership....I know that I have heard forever that they can't reprogram for larger tire sizes, but the dealership here that sells 285's swears that they can reprogram the computer for them (for $92.00 :D )...

quote - It takes like 15 minutes or so for it to copy and write to and from.

More like 5 on mine- I'll have to time it next time!

Drove my 04 first 15k miles without Juice, put it in and at 20k, Yep injectors again. took it off drove upto 30K no problems, put it back on, truck started bucking and hesitating when cold. I did find the fix for that however


OK, what did you find as the fix??With my 04 I have started buying Premier Diesel from the BP (Amoco). More power, 1 mpg better. It is more expensive generally about .10 per gallon more, but the extra 25 miles per tank makes up the extra $2.50 per tank to fill up.

With my 04 I have started buying Premier Diesel from the BP (Amoco).
I don't think I've ever seen multiple grades of Diesel here in Texas? Did you go to a truck stop to find multiple grades?