Vin Build Sheet

[Stranger ranger]

just wondering what the difference is. I used comp nine for two different vin numbers, both hd's, one chevy, one gmc.

the 05 gmc shows a nt9 tier 2 phase out but the 06 shows an nt8 tier 2 a

[sc4808]

This explains it.

 

Tier 2 Explination

[Stranger ranger]

ya I still in the dark.

[Stranger ranger]

Just out of curiosity, is there any effect on engine power output between the two? Is one more restrictive than the other?