3-4 Shift Shutter While Mid-throttle.

Mighty HD · July 1, 2007

We're getting ready to head on a 2000 mile round trip in three days.

The truck started acting a bit odd this week.

It started Thursday. I used remote start (Viper 791xv) to start the truck. It had been sitting idle for about 5 days. I go drive off and the shifts are super, super hard. 1-2, 2-3, and 3-4. Regardless of the % of throttle given, it was harsh. Enough that it would literally slam through the gears and nearly break loose my BFG MT 285's.

I got to my destination about a mile away. Shut it off, cameback and started with the key. Problem was magically gone.

I now have a very noticeable "shutter" type action on the 3-4 shift at mid throttle. It does it regardless of remote start or not.

Any ideas what this can be? Would a simple reflash solve it?

07 2500hd 4x4 6.0 3800 miles total. All fluid levels are good and clean.