Some customers who drive at elevations higher than 3,300 ft (1,000 m) may complain of a shift shock felt when shifting into 3rd, 5th and/or Reverse with no AT related DTCs stored. The symptom can be temporarily repaired using the AT initial learning procedure, but may recur after multiple driving cycles. Applicable situations: Shifting up: 2-3 or 4-5 Shifting down: 4-3 or 6-5 NOTE: Shifting from 2-3 or 4-3 is more likely to be felt due to the gear ratio. Shifting into Reverse: D-R, N-R or P-R Improper control logic of the TCM may cause improper learning of R-3-5 brake engaging speed when the vehicle is driven at high elevations. To correct this issue, the control logic of the TCM has been modified.