Has anyone had issues of slipping automatic transmission in 4 low lock? It feels just fine in 4 high and 4 high lock. When in 4 low lock the engine revs up until it finally catches and jerks once it engages. Fluid level is fine. All other gears feel normal. Dealer is 90 miles away but still under warrantee for 6 more months.

 

You are describing the auto trans shifting..........NOT slipping. It works differently in low, and feels different because of the torque and rpms. Perfectly normal.

Use the shifter and put in 2nd or 3rd yourself.

 

Talking about from a dead stop. Revs up before it ever moves the truck then it's a sudden jerk.