[cleatus12r]

Originally Posted by bukbugy

And now come the questions.
First of all Thanks a bunch, quick order and response to questions were great.
What I ordered was a 6 position with the following:
1-Whisper Mode
2-Stock
3-Fuel Sipper
4-25hp Heavy Tow
5-40hp Moderate Tow
6-65hp Standard Tow

The spec sheet shows:
1-Stock
2-Fuel Sipper
3-25hp Heavy Tow
4-40hp Moderate Tow
5-65hp Standard Tow

Can I get a clarification on this. It sound like position 2 is a little quieter (Whisper Mode) but it doesn't seem like a big difference. Is it possible that this position did not get put on? I can't answer about what went where on the chip. Does your chip actually HAVE 6 positions on it? All trucks seem to react differently to the Whisper Mode tuning. However, since you have a single shot injector truck, the Whisper Mode should make a really big difference when setup right for YOUR truck.

Now concerning the different Tow modes. What is considered heavy, moderate and standard? What is the reason for less hp on a heavy tow? Heavy would be in the neighborhood of 13K lbs. or more. Moderate usually constitutes a load of 8K to 12K. Light tow would be up to 6-8K lbs. The truth of the matter is, depending on the truck, the driving style, and the maximum EGT you can sustain or control dictates how much you can (or should) tow with each setting. The reason that the heavy tow program is "worth" a lot less power rating is that with a diesel powerplant, more power usually ALWAYS means more heat (EGT). Besides, towing a 15K load with a light duty truck with 300+ HP (designed for 215 HP) will kill drivetrain components in a hurry.I will use the truck for pulling a 30ft 5th wheel almost exclusively. Unless I'm on the beach or just around the house.

So what would the best hp setting and will that vary if I am in mountains (Va and WVa) or in the flats like eastern Va and NC? You will have to determine that. Like I stated before, there are a lot of variables and you need to drive each tune and decide which one gets the job done the best without skyrocketing EGT.

I did go for a quick spin and WOW the 65 hp really gets up and goes and I noticed the shift points changed quite a bit and the response on the shift was much smoother. Almost wanted me to hook up the camper just to see how it would run (gotta wait a couple more weeks though).

Lastly in the instructions it says that is is discouraged that you shift on the fly while under load. I understand that to mean whille towing, correct? Yep, for a couple reasons. First is that you're INSTANTLY changing the power level. Under certain conditions, this can shock the drivetrain and cause damage. Secondly, each tune has a lot of different engine control maps that dictate fueling rate and injection timing. The way the PCM and chip work, address lookups in the chip may be slightly delayed or skewed for a split second causing at minimum a "bump" or at worst, damage. Always TRY to allow a coast/decel or back off of the accelerator pedal before switching tunes.

Thanks a bunch,

b

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