New GM truck Owner: Tuner Questions

[leathermaneod]

Hi all,

New GM truck owner here. Just bought a 2018 Chevrolet 1500 Custom. I am the second owner, truck has 132,****** miles but seems to have been well maintained and is in great shape. Currently has a leaking oil cooler line and a broken exhaust manifold stud, both for which are going to be fixed on Monday by the dealer under my 30 day powertrain warranty. I am aware of the afm issues and would like to disable it, unless I am advised otherwise here. I also have a relatively slight shake at idle in drive, which I understand is common. I plan to change spark plugs, change engine and cabin air filters, and fluids as soon as possible. I also plan to run some Liqui Moly through it, but if none of that corrects the rough idle, I’d like a tuner to raise the drive idle rpm’s a bit. That and disable afm are all I want out of a tuner, nothing else. So I’m looking for recommendations. I don’t want to spend a fortune on features I don’t need. The trucks purpose is mainly to pull my 3500 pound, 16’ travel trailer about 10 times a year. That and some general run around, getting things like lumber or mulch or firewood occasionally. I want to take care of it and have it last as long as possible. Thanks in advance!

[CajunFries]

Any handheld tuner can disable the DOD. my recommendation if you’re going to tow quite often is to at least do the trans thermostat mod. (LINK: T stat flip mod) and if your trans temp is still kind of high while pulling in the summer, you can add a Trucool 40k cooler to that. In-line with the factory trans cooler. If you have the 6 speed trans, I would suggest you swap the torque converter out with one from a CTSV. It is not too expensive and it will prevent the stock converter from taking a dump and ruining the whole trans.

 

Also with that many miles, you can look into walnut blasting the intake valves. It’s got a rough idle probably from all the build ups. 
 

GL! 

[leathermaneod]

Thanks for the reply! Yes I am planning to look into the trans thermostat and keep an eye on temps in the meantime. Can most handheld tuners also adjust the idle speed? I’ve done a lot of reading so far and it sounds like that is one of the most reliable fixes for the rough idle in drive. It’s smooth as glass in park or neutral.

[CajunFries]

27 minutes ago, leathermaneod said:

Thanks for the reply! Yes I am planning to look into the trans thermostat and keep an eye on temps in the meantime. Can most handheld tuners also adjust the idle speed? I’ve done a lot of reading so far and it sounds like that is one of the most reliable fixes for the rough idle in drive. It’s smooth as glass in park or neutral.

I don’t know toooo much about handheld tuners. I had a Diablo Trinity T2 and it did let me raise the idle. But I think that is just a bandage to your problem. I never had any shake at idle in gear. Intake manifold is fairly easy to remove. Let it soak overnight in something like seafoam and use some kind of brush to loosen all the particles and suck the fluid out with a vacuum or use paper towels. Or pay someone to have them clean it with walnut blasting. You’ll probably see some gains in power, responds, MPG…. Just my 2 cents. 

[leathermaneod]

That sounds like a good idea. Not sure when I’ll get to it at this point, but I would rather do that than make changes to idle speed. I had read a very long thread with lots of peoples input saying that their brand new trucks had the slightly rough idle in gear and that it was due to GM setting the rpm’s too low for fuel economy reasons, but then there were also some saying fuel system and/or intake cleaning solved the issue. Is the Range module the best for just disabling afm?

[CajunFries]

For the price of the Range, I would rather spend that on a handheld tuner. You can do way more than the range.