New to me diesel TV

[Jshopes81]

Im not sure what all the 09s have as far as emissions but i think they do have an egr. I would get rid of that crap with one that can pass a visual inspection. Recirculating your exhaust gasses back through your motor is not good for it. Manufacturers have had to cut their life expectancies on motors because of this. Do not just delete the thing, that can and will eventually get you in trouble. You need to be able to pass a visual and computer check. In addition to the egr delete you should get a tuner that allows you to monitor engine vitals. I dont recomend this for the purpose of turning it up, but just for monitoring. They can alert you to a potential problem long before the idiot light dash guages can. You may also need it to over ride the cel that the egr delete may cause. You dont want to have it on for the egr and something else.

Otherwise the duramax/allison is a great combo. Keep your air filter clean and all should be good. I did see one of these suck a clogged filter back into the intake elbow once. It was the most expensive air filter ive ever heard of at 2500$ including the tow bill

[consolenut]

As per the Allison manual and allison and chevrolet dealer. Drop the fluid from the pan and change the spin on filter. Check for your self but Allison says filter in pan only changed during an overhaul or rebuild. Just be sure to put Allison fluid back in it. Be ready trans synd is expensive but well worth the money.

[CharlesinGA]

The OP is correct, the owners manual sucks, plain and simple, written by committees. One committee wrote the paragraphs on Tow Haul mode, another wrote the section on trailer towing, and a third wrote a section on "grade braking". each of these references one of the other sections, without explaining how to use Tow Haul, beyond the basic press the button, icon appears on dash, it changes shift points, yada, yada. No where does it mention that you have to press the brake pedal enough to make the brake lights come on, to activate the early downshifting (and I presume, lock up clutch engagement). After some searching, I found this............ (this is for 2014 models, I assume that a 2009 is probably the same)

"Tow/Haul mode, activated by a button on the shift lever, modifies the standard six-speed transmission’s shift mapping to take full advantage of the Sierra’s powerful new EcoTec3 engines. Under acceleration, shift points are higher for more power, while downshifts are initiated earlier to promote engine braking, reducing wear on the Sierra’s disc brakes.

With Tow/Haul mode engaged, Sierra’s Trailer Grade Braking is activated when the driver lightly applies the brakes. This feature initiates downshifts to assist with braking on long downgrades. In addition to slowing the vehicle more efficiently, Auto Grade Braking can reduce brake rotor temperatures by 100 degrees Celsius during a braking event"

https://media.gmc.com/media/us/en/gm...railering.html

Charles

[2Yung2 Quit]

I have a 2011 Silverado 3500 HD. For my truck there is an exhaust brake button on the dash.