Same, check on that CMP retard. I went through this code a few months ago.
https://www.gmt400.com/threads/scanner-tool-to-set-the-timing.42183/page-8#post-1320079
All of this. Strange it's not throwing a code, or not yet.
Mine ran pretty similar '97 5.7 until I dialed in the cam offset. I would check into that. Also, AC Delco cap and rotors only. The other cheap amazon stuff does not last at all I've found.
Related...
I have a '97 Z71 K1500 (3'rd door) and I always thought the driveshaft seemed huge also for a half ton. Same as your pics. I got the truck in '98 completely stock.
Wanted to post my experience doing this,
I used a cheap clear bluetooth ODB scanner (Foseal) and the Android DashCommand app, with the PID unlock for my truck year '97 ($10 for app and $10 for year unlock). Had to add PID Cam Retard CKP / CMP Correlation to the data grid on app. Spec is +2 to...
I just set mine last week, I used a cheap clear bluetooth ODB scanner and the Android DashCommand app, with the PID unlock for my truck year ($20 total for app and year unlock). Had to add PID Cam Retard CKP / CMP Correlation to the data grid on app. Spec is +2 to -2 degrees from what I read...