AFM disable in M5 gear

[Marky Dissod]

MT1 = 4L80E
MN8 = 4L85E (Heavy Duty)

MYC = 6L80E
MYD = 6L90E (Heavy Duty)

 

[swathdiver]

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.

No, you're right about the 2007 2500s having the 4L80. The OP mentioned AFM and M5 so I figured his for a 1500.

 

[buckwild27]

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?

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.

 

[1-oh-Hoe]

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.

 

[Doubeleive]

A 4L80 is a 4 speed tranny,
so you wont have a M5

the 2014 is most assuredly a 6sp

 

[donjetman]

the 2014 is most assuredly a 6sp

I know, but he said he had a 4L80 & M5?
something is wrong with that combo

 

[PPV_2018]

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 have never heard of this method to disable AFM.. is this only for GMT900’s ? More details please

 

[buckwild27]

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.

 

[Doubeleive]

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 buy 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.

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......

 

[buckwild27]

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.