Have been driving my 2014 Tahoe, 5.3 engine 4L80 trans with 125k on it in M5 in order to disable the AFM. I also on occasionally tow an approx 4000lb modified cargo/travel trailer. Will this cause any harm to the transmission?
AFM disable in M5 gear
- Thread starter Doc52
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donjetman
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A 4L80 is a 4 speed tranny,
so you wont have a M5
pretty sure 6 speed wasn’t standard until K2 generation (2015-2020)
swathdiver
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Why bother Doc? Just drive it normally and keep clean oil in the motor and change it often. Dirty, high mileage oil is AFMs worst enemy. If you are really bothered by it, get the motor/transmission tuned by BlackBear and they will turn it off.
You have a 6L80 transmission, not a 4-speed. Unless of course you modified the truck. Change the fluid every 40-45K miles and it will last you a long, long time. No, it won't hurt anything to tow in 5th.
@PPV_2018 The 6L80 was introduced in the GMT900s for the 2007 model year. Other vehicle lines may have used it or it's sibling, the 6L90, a year or so earlier.
Marky Dissod
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Since it already has 125k miles, hopefully the ATF been changed every 40k miles?
Not only is it a good idea to tow in M5, you should ALSO use Tow / Haul mode, especially when the road is NOT flat.
For better results, have your ecm & tcm tuned. Among many other things, make sure Engine Half@$$ gets disabled,
and the torque converter clutch behavior is addressed for improved longevity / durability.
Hmm interesting.. swore i thought i had a 4L80 in my ‘07 2500.. but i very well could be mistaken. Guess it coulda been 6L80.
mikez71
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Not all GMT900's. I believe the standard Tahoe/Suburban got the 6l80 in 2009.
And from what I can tell, (downloaded HPTuners repository file) the '07 Silverado 2500HD was a 4 speed.
And from what I can tell, (downloaded HPTuners repository file) the '07 Silverado 2500HD was a 4 speed.
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Marky Dissod
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MT1 = 4L80E
MN8 = 4L85E (Heavy Duty)
MYC = 6L80E
MYD = 6L90E (Heavy Duty)
MN8 = 4L85E (Heavy Duty)
MYC = 6L80E
MYD = 6L90E (Heavy Duty)
swathdiver
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No, you're right about the 2007 2500s having the 4L80. The OP mentioned AFM and M5 so I figured his for a 1500.
You can disable the AFM by unplugging the sensor on the brake booster hose. That's the sensor that gives the ok to go into 4 cylinder mode.
I was super happy with the DiabloSport Trinity. I put the mild 87 oct tune, AFM delete and firm trans shift. It really brought it to life.
I found it on marketplace for half off. So for 200 bucks it was cheaper than the pedalcommander or an OBD AFM module. It can read codes too! I plan on doing some towing so when I do it's simple enough to plug in and flash a more aggressive tune and run some 93. Or keep it mild for around town and save some $$$.
If I ever throw some perf parts on it I also have the option of a custom tune like the ones from diablew.
I found it on marketplace for half off. So for 200 bucks it was cheaper than the pedalcommander or an OBD AFM module. It can read codes too! I plan on doing some towing so when I do it's simple enough to plug in and flash a more aggressive tune and run some 93. Or keep it mild for around town and save some $$$.
If I ever throw some perf parts on it I also have the option of a custom tune like the ones from diablew.
the 2014 is most assuredly a 6sp
donjetman
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I have never heard of this method to disable AFM.. is this only for GMT900’s ? More details please
I keep forgetting that the suv 14 is a previous model it does work on the k2's. But the gmt900 has the same plug. I shut it off in my 13 by tuning so I can't confirm it works that way on the gmt900. It does give a check engine light but it doesn't affect anything other then not letting it go into v4 mode. It tells the ecm you have enough vacuum to allow it to switch.
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figured this was the case, they design many things to be nanny watched, so while yes you could make it do this or that, it's going to nag you, most of us do not like the cel on as when something else happens you never know......
This is more for those that are going to get a tune later or don't want to spend the money on a range device.
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