Jsdirt

It does NOT lock the ECU / PCM. It locks the tool so you can't upload it to more than one vehicle. It also captures your stock info in the tool, which cannot be uploaded to any vehicle but the original. With a J-box you can wipe the PCM and start over. Look at the link I posted to the picture straight from the manual - "If a service facility reprograms your vehicle's computer with an update, your Hypertech Power Tuning will be erased."

Crap! Sorry to hear that. Those are great trucks - I see many well over 300k still running.

AMEN to that! If I had my way, I wouldn't drive anything built after 1972! We've got a '86 Grand Marquis daily driver that's all stock and original. Still runs the original OE in-tank fuel pump - 36 years, 285k miles! Try that on anything built in the last 25 years. We take it off the road every winter, otherwise it would've rotted away to nothing 25 years ago. The road salt up here is brutal. We run a '93 Volvo 940 for a winter beater. They used top quality metals and paint on this thing - been in New England winters since it rolled off the showroom floor in '92, and has minimal rust and no rot. Slow as slow can get, but it's as reliable as a stone ax, totally unlike my Silverado has been. I'm at 117k on the Silverado, and I'm planning an engine swap already due to low oil pressure. Started burning oil at 50k miles! Had nothing but trouble with this thing since DAY 1. Brakes, ball joints, rear end failure at 97k, trans at 103k - one thing after another.

I've got the Hypertech tuner on mine - bought it in '07 when my truck was still brand new. Got a cold air intake, and Corsa cat back system, and that's it as far as mods go. It woke the truck up pretty good. I have all the transmission parameters set to stock, since my transmission is built to the moon, so all of that has been taken care of by the builder. I can actually break stuff inside the trans if I go ramping up shift firmness, since my pump is already set to run in triple-digit pressures. Back when the truck had the original trans (before 103k miles), I cranked up the shift firmness as high as it would go. That probably got me several thousand more miles out of it. Yours is built MUCH better than mine, so you won't have to worry about that too much. From '07-up, parts quality of these trucks really took a nosedive. As far as shift RPM and rev limits, I left all that alone, since there was no reason to increase or decrease any of that from stock. One time I screwed up and changed the rear end gearing in the tuner - thought I had set it back to where it should have been, but I missed a key step. Every light on the cluster lit up, shift points were screwed up, and the truck was bucking and surging like crazy! Luckily I didn't break anything. The shifts were violent. I only drove it 4 miles that way.

Yeah, there's no need to screw with rev limits or shift points unless you installed an aggressive camshaft and heavier valve springs, and need the thing to rev out to 7k to make use of the top-end power.

Rev limits and shift points are adjustable in the tuner. Someone jacked it way up to the moon, and probably didn't understand what was happening when it hit the rev limiter, and dumped the truck. I hate when people do that and don't include the tuner! Pretty much screwed without it.

Doesn't need a new ECM. You can reprogram it with factory tuning, or, a tuner shop can tune over it.

You need the actual unit in order to return the computer to stock. Without it, your only option is to reprogram your existing computer at a garage, or tuner shop. https://postimg.cc/CZjf2FkY

It says right in the directions that they can't help you without the original programmer, if I remember right. I'll take a look at it again in a bit here.

Gotcha. They set the shift points way too high. On a stock engine, they should be set at 5,500 RPM. Mine shifted there with the stock trans. With the modified trans I now have it shifts around 5,300 or so.

Without that programmer, the only thing you can do is have the ECU wiped and reprogrammed at a shop or mobile programmer that has a J-box. It's costs to get the required info from GM's website, plus the persons time, so you'll be into it for at least $200 I figure. Might be cheaper in AZ. Either that or grab another one out of the boneyard (which might require programming anyway to get certain options to work), or, find one of those guys on eBay that'll sell you a used ECU, and they'll program your VIN and options into it prior to shipping it out. What exactly was done wrong? Wrong axle ratio? That's about the only thing that'll screw up drivability with a Hypertech. Those things are so easy to use, a 4 year old could do it.

You need to go over EVERY part of that installation. You probably need to use better connectors from the sound of it. Some of these codes could be unrelated, but you need to rule that out first.

What codes do you have? Bad throttle body or connector / wiring to it will cause limp.

That wouldn't cause the pedal to drop to the floor upon startup.

Most HD trucks do. If it's got the D-Max, I'd wager it's Hydroboost.