6.6L Duramax Diesel (L5P)

205 topics in this forum

1. Exhaust heat while towing!

   By PBNB, June 20
   • 0 replies
   • 133 views
   • 
   • PBNB
   • June 20

2. What is this light called?

   By Bob 5th Wheel, April 2
   • 3 replies
   • 628 views
   • 
   • carkhz316
   • April 5

3. is Boost tube loose?

   By MG386, March 30
   • 1 reply
   • 374 views
   • 
   • PBNB
   • May 13

4. Towing a 5th Wheel

   By DBeau, March 30   

   • towing
   • 5th wheel
   • (and 1 more)

     Tagged with:

     • towing
     • 5th wheel
     • lifted truck
   • 4 replies
   • 765 views
   • 
   • tonto340
   • April 1

5. L5P Android Auto Gauge app

   By mkirkland, March 26
   • 6 replies
   • 756 views
   • 
   • mkirkland
   • April 25

6. Frame repair

   By MHP275, February 2
   • 4 replies
   • 549 views
   • 
   • newdude
   • March 3

7. Engine temp

   By Ultlukasz, December 15, 2025
   • 1 reply
   • 232 views
   • 
   • MG386
   • February 3

8. Aftermarket DEF filter?

   By RNAV, May 29, 2025
   • 2 replies
   • 1.4k views
   • 
   • redwngr
   • June 8, 2025

9. 11 quarts to fill my truck after oil change 1 2

   By 64BAwagon, May 20, 2025
   • 23 replies
   • 19.7k views
   • 
   • Z45
   • October 28, 2025

10. P20B9 DEF Heater Failure, workaround for limp mode?

    By Michael Butts, April 13, 2025
    • 7 replies
    • 4.2k views
    • 
    • mjm-1957
    • July 19, 2025

11. Loud humming noise when idling in cold temps

    By Taylor_S, March 21, 2025
    • 8 replies
    • 2.1k views
    • 
    • Sonny R
    • June 25, 2025

12. DEF fuse

    By Outdoorsmen22, March 13, 2025
    • 2 replies
    • 3.2k views
    • 
    • Outdoorsmen22
    • March 13, 2025

13. 3500 Duramax engine brake not working & throttle sticking

    By owner, March 4, 2025
    • 3 replies
    • 3k views
    • 
    • GMCustomerService
    • March 10, 2025

14. problems with recall???

    By buelldude, February 24, 2025
    • 2 replies
    • 2.3k views
    • 
    • Chevyfan3
    • February 25, 2025

15. Another valve body bites the dust. Anyone know how long the wait is now?

    By fishnitro, February 3, 2025
    • 7 replies
    • 6.2k views
    • 
    • fishnitro
    • February 20, 2025

16. Rear Glass Alignment Tabs

    By Daniel_B, February 2, 2025
    • 1 reply
    • 1k views
    • 
    • SoCal Angler
    • February 4, 2025

17. U062F check engine code

    By Nickg352, January 20, 2025
    • 2 replies
    • 6k views
    • 
    • Nickg352
    • January 20, 2025

18. Recent Recall

    By RCTaylor, January 16, 2025
    • 5 replies
    • 3.5k views
    • 
    • RCTaylor
    • February 4

19. 18, 19, 20+

    By James Beyer, January 9, 2025
    • 2 replies
    • 1.8k views
    • 
    • James Beyer
    • January 14, 2025

20. 2020 2500HD (L5P) won't crank after replacing both batteries.

    By RobVee, January 2, 2025
    • 1 reply
    • 1.9k views
    • 
    • Doughacker
    • January 20, 2025

21. trans pan from RA

    By buelldude, December 27, 2024
    • 8 replies
    • 2.3k views
    • 
    • asilverblazer
    • December 30, 2024

22. Transmission Control Valve Recall

    By Whip, December 27, 2024
    • 9 replies
    • 12.8k views
    • 
    • Courtney Johnson
    • February 22

23. Momentary rear wheel lockup recall

    By XY74, November 11, 2024
    • 10 replies
    • 8.7k views
    • 
    • Zane
    • March 6

24. 2025 GMC Sierra 2500 6.6L Duramax Transmission Leak 1 2

    By Jrod.Milton, October 22, 2024
    • 24 replies
    • 23.8k views
    • 
    • vscott
    • February 20

25. 2025 transmission RPM issue - cruise control holding gear

    By euromade, October 18, 2024
    • 2 replies
    • 2.8k views
    • 
    • Rick_
    • October 25, 2024