- Jan 1, 2023
- 3,480
- 7,275
I just finished hooking up my Ultimate9 that I removed from my 2023 ZR2. All I can say is HOLY ****!!! This thing really wakes up the 6.6L Duramax and I'm loving the throttle response now. I can't imagine not having one of these on any of my trucks...amazing product and very high quality.