This was a trial! 4th belt bought fits & is longer than any belt specified for 2000 Silverado 2500HD 6 liter. No idea why a longer than stock belt for 130 amp alternator is required. One step longer or shorter will not fit within small operating range of tensioner.
New alternator has output...
Tried to determine correct belt for larger frame alternator, ordered belt that was for Duramax with 130 alternator but w/o air pump. It measures same as original. Searched more, then installed new larger alternator with original belt. Original belt is Gates 1197. 6.6 belt tensioner has much...