Engine Miss

[zorrro]

My 2001 2500HD seems to miss or pulsate whenever I hold it at constant speed. It's not bad, just noticeable enough to bug me whenever I'm on the open road. I had a FORD work vehicle do this only in OD, when the torque converter was going bad (some kind of OD soleniod clutch slippy thing). It kind of feels the same but the GMC seems to do it at every speed I try to maintain for a period of time. The truck is pretty new to me, but I don't think this is normal. There is also a slight fluctuation in idle speed, not smooth as glass. I would appreciate any help out there. Thanks...........Zorrro

 

INFO:

8.1 Liter

Allison

83,000 miles

Bone stock

No check engine light