Normal Mode Powertrain Grade Braking Feature (PIT5202F)

Publication date: 2021-10-11
Reference number: PIT5202F
Supersedes refnos: PIT5202, PIT5202A, PIT5202B, PIT5202C, PIT5202D, PIT5202E

NORMAL MODE POWERTRAIN GRADE BRAKING FEATURE

TECHNICAL SERVICE BULLETIN

Reference Number(s): PIT5202F, Date of Issue: Oct 11, 2021

SERVICE INFORMATION

Brand:	Model:	Model Year:		VIN:		Engine:	Transmission:
Brand:	Model:	from	to	from	to	Engine:	Transmission:
Cadillac	Escalade	2013-2020		All	All	All	6L80 RPO MYC, 6L90 RPO MYD or 8L90 RPO M5U
Chevrolet	Avalanche	2013		All	All	All	6L80 RPO MYC, 6L90 RPO MYD or 8L90 RPO M5U
Chevrolet	Express Van	2014-2021		All	All	All	6L80 RPO MYC, 6L90 RPO MYD, 8L90 RPO M5U/MDQ
Chevrolet	Silverado	2013-2018		All	All	All	6L80 RPO MYC, 6L90 RPO MYD or 8L90 RPO M5U
Chevrolet	Silverado LD	2019		All	All	All	6L80 RPO MYC
Chevrolet	Silverado 2500/3500	2019		All	All	All	6L90 RPO MYD
Chevrolet	Suburban	2013-2020		All	All	All	6L80 RPO MYC, 6L90 RPO MYD or 8L90 RPO M5U
Chevrolet	Tahoe	2013-2020		All	All	All	6L80 RPO MYC, 6L90 RPO MYD or 8L90 RPO M5U
GMC	Savana Van	2014-2021		All	All	All	6L80 RPO MYC, 6L90 RPO MYD, 8L90 RPO M5U/MDQ
GMC	Sierra	2013-2018		All	All	All	6L80 RPO MYC, 6L90 RPO MYD or 8L90 RPO M5U
GMC	Sierra Limited	2019		All	All	All	6L80 RPO MYC
GMC	Sierra 2500/3500	2019		All	All	All	6L90 RPO MYD
GMC	Yukon	2013-2021		All	All	All	6L80 RPO MYC, 6L90 RPO MYD or 8L90 RPO M5U

Supersession Statement

This PI was superseded to add 2019 model years. Please discard PIT5202D.

Starting with some 2013 models, Powertrain Grade Braking is now enabled while in Normal mode (Normal mode = Tow/Haul mode OFF), along with a new DIC message "GRADE BRAKING ON" or "GRADE BRAKING ACTIVE" when it goes active for the first time. Powertrain grade braking has been available since 2009 on LD models and since 2007 on HD models, but Tow/Haul mode had to be selected. This feature (powertrain grade braking) should not be confused with "Cruise Grade Braking".

For more information on Cruise Grade Braking see the owner's manual or the latest version of bulletin 08-07-30- 030.

PURPOSE

Normal mode powertrain grade braking assists when driving on a downhill grade to help maintain desired vehicle speed by using the engine and transmission to slow the vehicle.
Helps reduce brake temperatures and wear on the traditional braking system.

ACTIVATION

Normal mode powertrain grade braking defaults to "ON" after each ignition key cycle.
To disable or enable all grade braking within the current ignition key cycle, press and hold the Tow/Haul button for three seconds.
No grade braking is available in Range Selection Mode (Manual Shift Mode).
For grade braking to activate it requires the driver to apply steady brake pedal pressure to maintain desired speed while driving on a downhill grade. The vehicle's modules monitor the amount of brake pedal apply, vehicle deceleration rates, and other factors to determine if normal mode powertrain grade braking is necessary. When the feature activates for the first time that ignition cycle, the DIC will display "Grade Braking On" or "Grade Braking Active" and you will notice the transmission down shifts and engine RPM increases. At this point, if the brake pedal is released the transmission will hold the current gear. If additional engine/transmission braking is needed to help maintain desired speed, reapply steady brake pedal pressure and additional down shifts may occur.
Normal mode powertrain grade braking will have a less aggressive transmission down shift schedule than Tow/Haul mode powertrain grade braking.
Grade-braking can be exited by depressing the accelerator pedal.

MESSAGES

GRADE BRAKING DISABLED or OFF: This message displays when the grade braking has been disabled with the tow/haul mode button on the end of the shift lever.
GRADE BRAKING ENABLED or ON: This message displays when the grade braking has been enabled with the tow/haul mode button on the end of the shift lever.
GRADE BRAKING ON or ACTIVE: This message displays when the grade braking has been activated while driving on downhill grades. This message will only appear the first time the feature is activated in an ignition cycle. This message will not display if Cruise Control Grade Braking goes active.

NOTE:

On 2016 to 2019 model year Express and Savana Vans, there are NO DIC messages indicating grade braking is Enabled, Disabled or Active. The grade braking feature is operational, but there are no DIC messages. Every time the ignition is cycled on, the grade braking feature is enabled. After that point, if the Tow/Haul button is pressed and held for three seconds, the feature will be disabled. If the Tow/Haul button is pressed and held again, it is enabled and so on.

Remember, every time the ignition is cycled on, the grade braking feature will be enabled.