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Posted
2 hours ago, aliveguy5 said:

@rRandom I feel exactly how you do and I had the same feeling in my 2020 TB. Brakes worked much better with a trailer attached, and I have to work more unloaded. Same exact feeling on my 2021 HD. I wonder if there is some kind of sensor that increases the pressure when it sense a trailer or load. I'd love to have an engineer respond to this because I do wish my brakes felt like they do when loaded all the time. Do they make an adapter to plug in that will make the truck think a trailer is attached? If so that'd be a great test. 

Wonder if you plug in a 4 to 7pin adapter? 

Posted
19 hours ago, Grjfer said:

Wonder if you plug in a 4 to 7pin adapter? 

I am open to learning but to my knowledge this adapter only re-maps pin positions to a new location.  There is no cross connection or load being applied so I would not seem like this would have any impact. 

  • Like 1
Posted
On 7/16/2021 at 4:33 PM, nutdriver said:

I also have noticed that my 2021 3500 brakes are not as strong as I would like.  I wonder if some of the sense that the brakes perform better with a trailer attached is that the trailer brakes are helping to also stop the truck?  We have the capacity to increase the power going to the trailer brakes relative to applied pedal pressure.  As a result, we can dial in the braking sensation we are looking for.  Not saying there is not something more mysterious going on but sharing another theory.

I follow your logic here and it shouldn't be dismissed. I've tested my brakes with and without trailer brakes and everything feels tighter when I'm towing. I have more feedback in the brake pedal and response just seems better. Sometimes coming up to a light (unloaded) I feel as if the TC isn't unlocking quick enough and torque of the motor is pushing it ahead. There are other times the brakes feel exactly the same and truck doesn't lurch... My head is going towards the TC not unlocking but I'm not a mechanic or expert so I could be way off. 

  • 3 weeks later...
Posted
On 8/13/2020 at 5:45 PM, gSwift said:

I think i've finally gotten used to it, but I definitely feel the same! It feels noting like my last three 1500's or my Yukon. I wondered if it has anything to do with the weight of the vehicle.

I’m used to it as well but it’s does take more effort to stop and seems to take forever to stop and stops hard. It’s a odd feeling. 
when I drive my wife’s explorer I stop really fast and hard the first couples stops lol. 

Posted

Yeah I just got the 2021 gmc 3500hd regular cab 8ft bed srw 4x4 sle my truck is only 6640 curb weight and my breaks were so much better than the crew cab Denali dutamax srw curb weight on that 8370 you can feel that 1700 pound difference I also never creep but definitely more pressure required at red light then my ford f550 

20210726_035531.jpg

  • 3 weeks later...
Posted

I just went from a 2020 1500 to this 2021 2500 and the brakes are awful on the 2500 I just had an accident in a drive through the truck creeped with the brakes applied and wham I hit the lady in front of me. You really have to trounce on these brakes they almost feel like there is no power assistance at all. I HATE these brakes. The 1500 brakes were 100% fine and normal feeling.

Posted

I had this problem on my 2021 AT4. Very soft brakes that would only get firmer if I pumped the pedal, and creeping at stop lights. 

 

This fixed the problem for me: place the truck in park. Depress the brake pedal as far down to the floor as physically possible. Release the brake pedal and let it travel on its own all the way to the top. Repeat the process one more time. 

 

After doing this, my brakes act as I would expect on a truck this size. 

  • Thanks 2
Posted
1 hour ago, TheElementalCashew said:

I had this problem on my 2021 AT4. Very soft brakes that would only get firmer if I pumped the pedal, and creeping at stop lights. 

 

This fixed the problem for me: place the truck in park. Depress the brake pedal as far down to the floor as physically possible. Release the brake pedal and let it travel on its own all the way to the top. Repeat the process one more time. 

 

After doing this, my brakes act as I would expect on a truck this size. 

I will try this and thank you!

Posted

While you could have a problem that the dealership or mechanic should check out. 

 

If you were to look into upgrading your rotors and brake pads.  Look into PowerStop (https://www.powerstop.com/).  I've have had these on nearly all of my trucks.  Then too ad EBC (https://ebcbrakes.com/) brake pads to the PS rotors. 

You will notice a huge difference. Just make sure you read and FOLLOW the PowerStop instructions on breaking in the rotors and pads!!! VERY IMPORTANT!

 

 

 

Posted
56 minutes ago, SlowerTrafficKeepRIght said:

While you could have a problem that the dealership or mechanic should check out. 

 

If you were to look into upgrading your rotors and brake pads.  Look into PowerStop (https://www.powerstop.com/).  I've have had these on nearly all of my trucks.  Then too ad EBC (https://ebcbrakes.com/) brake pads to the PS rotors. 

You will notice a huge difference. Just make sure you read and FOLLOW the PowerStop instructions on breaking in the rotors and pads!!! VERY IMPORTANT!

 

 

 

I don't feel it's a rotor/pad issue rather a boost issue. The pedal travel is so far down, but it will stop. A few pumps of the brake pedal will firm my pedal pressure greatly while also allowing for the brakes to activate at the top of the stroke rather than nearly at the bottom. 

Posted
22 minutes ago, Grjfer said:

I don't feel it's a rotor/pad issue rather a boost issue. The pedal travel is so far down, but it will stop. A few pumps of the brake pedal will firm my pedal pressure greatly while also allowing for the brakes to activate at the top of the stroke rather than nearly at the bottom. 

I feel the same way... If I lay on the brakes loaded or unloaded I stop very controlled and quickly. It just seems that the pedal travel to get to that point in consistent. I wonder if I should bleed the brakes. 

Posted
6 hours ago, TheElementalCashew said:

I had this problem on my 2021 AT4. Very soft brakes that would only get firmer if I pumped the pedal, and creeping at stop lights. 

 

This fixed the problem for me: place the truck in park. Depress the brake pedal as far down to the floor as physically possible. Release the brake pedal and let it travel on its own all the way to the top. Repeat the process one more time. 

 

After doing this, my brakes act as I would expect on a truck this size. 

No sure why this works, but it made a HUGE difference. 

Posted

I had a similar issue. I looked under the dash on my 2020 2500HD and the hydroboost was leaking. Mild leak, but the booster was wet under the dash. Got the hydroboost replaced under warranty and all good now. Brake pedal feel is a lot better and stopping power is greatly improved. 

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