2015 Sierra brakes/vacuum issue at very low speeds

[2015 High Miler]

My truck has had this issue for quite some time but seems to be getting worse. It does have 230,000 miles so it may be just time to replace the vacuum pump.  
 

What happens is at a drive through speed or waiting in line at a drive through car wash , the brakes will get a very hard peddle and you really have to push VERY hard or you will not stop rolling. I have found that if I put in neutral and give it a light throttle, it will bring the peddle back for a few more stops before having to do it again.   What is involved in this repair? 
 

I tried a search but I was not getting any good returns. 
 

Thanks in advance

 

 

[Sir Dan]

I know there was a recall that addressed this issue on my 2016 that involved software flash to help avoid this problem with more electric boost. As the vacuum pump wears it gets to the point that even the electric boost can't help.

[sk]

There are 2 fixes.  One was a recall which just re-programmed the software and didn't do much.  The other is  a new-style vacuum pump.  The design of it was changed but GM never created a recall so unfortunately you need to do it on your own nickel.

 

There are tons of threads on the forums if you search for something like "hard brake" or "pedal".

[2015 High Miler]

Thanks, I have found a few threads on it after posting here.  Any idea an what the NEW PN is?  

 

[sk]

I had mine done years ago (March 2018) under warranty but here are the parts listed on my work order:

 

12669488  Pump

23135220  Booster

20925765  Cylinder

23135228  Pipe

19353126  Fluid

19287401  Cleaner