6 Speed Transmission Hack

[ChevyBrad1500]

I have a 2015 Silverado 5.3 6 speed. Another member (sorry I don't remember his name) had posted that the transmission shifts much better if you turn off grade braking (hold in tow haul button for 10 seconds) and turn off traction control (switch under the radio). He is right. The truck seems like a different truck. Seems like it's much faster. I also noticed it seemed to hold V4 longer when cruising at 60 mph than with it on, so I'm thinking it may help with mpg. I'll test mpg on the next trip I go on to SAMs club, which is 1.5 hrs away and I normally get 21 mpg. I wonder if it helps 0-60, because it feels much faster.

[SkiDooNick700]

1.5 hrs to a Sams Club?!!

 

Haha, I am going to try this today on my way home from work for kicks.

[Britt Lifsey]

Interesting! I've not been unhappy with my shifts but might try this just to see what it does. I assume it is needed every startup?

[HondaHawkGT]

The downside of it is that your brake life will be shortened by a decent amount.

[Justin MacGillivray]

The downside of it is that your brake life will be shortened by a decent amount.

 

I've used this method yesterday and today. Noticed smoother shifts, but also that I have to break earlier and harder than before. So yea it will impact your brake pads life. But for when I'm stuck in traffic, I feel like it'll be worth it for my sanity. If I am just getting on the highway and driving somewhere, I won't bother with it. I only get a hard or flare shift 2-3 when jumping hard on the gas, so cruising isn't an issue.

[newdude]

This all seems very...placebo effect...been behind the wheel of a few of these...zero difference with grade brake enabled or disabled...

[sk]

MODS:

 

Could we merge these. This is about the 3rd or 4th thread talking about this.

[zert100]

This all seems very...placebo effect...been behind the wheel of a few of these...zero difference with grade brake enabled or disabled...

 

What he said!

[Rkaroll953]

ive done both and dont notice any difference and i read that thread all the way through

[tnchevy]

Same here, if there is a difference I haven't noticed it. I think it is just like the transfer case update from last year, just in people's mind that it is doing better. Hopefully I am wrong.

[drparker7]

if you due this can you turn the traction control back on

[cbrsilv15]

Yeah, just hit the same switch you turned it off with. Lol!

[SouthernSilveradoGuy85]

I don't have a problem with the shifts once it was out of learn mode. Also there's a reason for grade braking which is to help with brake life and also it helps the truck stick to the cruise control speed even with a lot of hills. I can understand it may feel a little better with TC off, but it probably isn't enough to notice a huge difference. These trucks also have TQ management so you probably won't feel much different at take off from a stop with TC off. Like someone said, it may be more of your mind playing tricks on you. You want it to be better so you make yourself think that it helps. It's like if you buy spark plugs that advertise that it adds power (like e3) and when you change them out you think you feel an HP gain rather it's actually the same or only a couple HP.

[sk]

if you due this can you turn the traction control back on

 

This is not turning off the traction control, it's turning off the Grade Braking (different system).

[Britt Lifsey]

 

This is not turning off the traction control, it's turning off the Grade Braking (different system).

From OP:

" the transmission shifts much better if you turn off grade braking (hold in tow haul button for 10 seconds) and turn off traction control (switch under the radio)."