I've noticed a few times when cruising 65-70 in my truck that the RPM will surge 100-200 RPM... maybe 300max. Very subtle smooth surging not an abrupt or harsh jump.

Anyone else had anything like this, or have any insight as to what might be a cause?

 

Mine does it, but not consistently.
I haven't looked into it.
Mine is tuned and I don't recall if it did it stock or not.

 

Negative, mine doesn't.

 

Nothing here Noah.

 

Nah, not here

 

it's not consistent at all, very random actually... and seems to be worse on long trips. I'm assuming it's something in the tune but wouldn't even know where to start looking. My fear is something with the converter.

 

Last week I noticed the tach needle wasn't steady while cruising at 60mph. Rpms fluctuated 100-300. I wondered how accurate the gauges are.

 

Do you still have the AFM in your tune. It has a time out IIRC. So anytime the V8 mode kicks back in the rpm's will change, as the converter unlocks for a couple seconds it goes into V8 and back to V4 again. This will give you a surge if you're paying attention.

I cant remember the timing... but it resets every time you demand V8, hence the irregularity.

I could be 100% out to lunch on that though...

 

I have it too. Don't think its AFM either

 

AFM is disabled in my tune, still does it.
There is a slight change in engine sound so I don't think it's a gauge issue.