Supercharged111
Truly Awesome
- Joined
- Aug 20, 2015
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The switch would have been in the late '80s or early '90s. Your Suburban has a honeycomb catalyst. I don't know if early GMT400s had pellets because both my trucks had them cut off by previous owners.
My 88 had the pellet style. All Vortecs had honeycomb, but ike you I don't know where exactly that change occurred.