6.6L Duramax Diesel & Allison Powertrain (L5P/MGM)

183 topics in this forum

1. 2022 Silverado 2500HD Duramax Transmission Temp High with Normal Driving, Not Towing 1 2 3

   By D Fowers, July 20, 2022
   • 43 replies
   • 17.4k views
   • 
   • Liroadside
   • Yesterday at 12:40 PM

3. Momentary rear wheel lockup recall

   By XY74, November 11
   • 3 replies
   • 403 views
   • 
   • redwngr
   • Tuesday at 11:18 PM

4. Banks Derringer on 2024? 1 2 3

   By bass mechanic, May 22, 2023
   • 41 replies
   • 19.3k views
   • 
   • davidm767
   • November 9

5. diesel fuel additives

   By tc64, September 16, 2020
   • 12 replies
   • 13.5k views
   • 
   • Chadw90
   • November 9

6. 2025 GMC Sierra 2500 6.6L Duramax Transmission Leak

   By Jrod.Milton, October 22
   • 7 replies
   • 905 views
   • 
   • Chevyfan3
   • November 2

7. Waiting on a part for over 2 months.

   By DkJohnstone, October 16
   • 4 replies
   • 547 views
   • 
   • Chevyfan3
   • October 29

8. 2025 transmission RPM issue - cruise control holding gear

   By euromade, October 18
   • 2 replies
   • 390 views
   • 
   • Rick_
   • October 25

9. 2024 3500 oil leak 1 2 3

   By Rototerrier, November 11, 2023
   • 36 replies
   • 113.8k views
   • 
   • redwngr
   • October 10

10. Diesel in cold weather

    By sno1, May 2
    • 6 replies
    • 1.9k views
    • 
    • RichaudGagnier
    • October 7

11. Need Deleted L5P Advice 1 2 3

    By Brozat4, January 30, 2021
    • 34 replies
    • 62.3k views
    • 
    • 2500W/T
    • October 7

12. Transmission fluid and filter change, temperature to check fluid level?? 1 2

    By XY74, December 22, 2022
    • 18 replies
    • 15k views
    • 
    • 64BAwagon
    • September 19

13. Oil Filter

    By lamoon78, January 19
    • 5 replies
    • 4.1k views
    • 
    • Black02Silverado
    • September 16

14. 2023 duramax slight shake at idle

    By fjcanepa07, July 4
    • 11 replies
    • 1.9k views
    • 
    • redwngr
    • August 25

15. Towing

    By Chfc2, July 23
    • 10 replies
    • 1.2k views
    • 
    • newdude
    • August 5

16. 2020 Silverado HD Duramax "Low Fuel Warning" with tank full

    By xray58, July 28
    • 1 reply
    • 336 views
    • 
    • GMCustomerService
    • July 29

17. Transmission oil leak - what part is it leaking from ?

    By Eswaroop, July 8
    • 7 replies
    • 1k views
    • 
    • newdude
    • July 13

18. wild

    By daywright, July 9
    • 0 replies
    • 614 views
    • 
    • daywright
    • July 9

19. Steering gear box

    By Sabe, July 6
    • 0 replies
    • 519 views
    • 
    • Sabe
    • July 6

20. Humming noise when cold started??

    By 2023 problem, March 16, 2023
    • 7 replies
    • 5.9k views
    • 
    • Sonny R
    • July 5

21. Back Up Camera Solutions for a Truck Camper please

    By Truck Novice, June 8
    • 3 replies
    • 901 views
    • 
    • Another JR
    • July 5

22. Does a 2024 Duramax have fewer emissions issues? 1 2 3

    By Rabbittown, January 31
    • 34 replies
    • 8.9k views
    • 
    • Racer61x
    • June 10

23. Gear indicator on cluster for 2024 GMC Sierra 3500HD

    By Truck Novice, April 23
    • 14 replies
    • 3.4k views
    • 
    • 64BAwagon
    • May 26

24. 2025 8.3L Duramax

    By C/K Man, January 31
    • 1 reply
    • 4.2k views
    • 
    • 64BAwagon
    • May 26

25. 2020 and up, dpf system recall 1 2 3 4

    By shadow gray 2020 hd, May 25, 2022
    • 47 replies
    • 31.3k views
    • 
    • BB&Chiveon
    • May 1

26. Gassing up while running

    By Carlos Clark II MD, January 5
    • 12 replies
    • 2.4k views
    • 
    • sstoner911
    • April 5