Automatic transmission's Gear Down and Up Ratio settings affect wrong gear

Branch: ‘Binary’ build from the Unreal Launcher

Build version: 4.10.2-2818068+++depot+UE4-Releases+4.10

Issue: Down Ratio and Up Ratio settings of Gear x actually affect Gear x-2. Happens with both C++ and Blueprint.

77838-ue4_auto_gears_bug.png

Steps to reproduce:

  1. Use the Blueprint Vehicle Advanced template
  2. In the vehicle’s Transmission Setup make sure Automatic Transmission is ticked (it’s ticked by default)
  3. Control test (optional): Drive the car to see how it normally shifts
  4. Set Gear 3’s Up Ratio to 1.0
  5. Drive the car. It’ll never reach 2nd gear.
  6. Reset the Transmission Setup
  7. Set Gear 4’s Up Ratio to 1.0
  8. Drive the car. It’ll never reach 3rd gear.
  9. Reset the Transmission Setup
  10. Set Gear 4’s Down Ratio to 0.0
  11. Accelerate until reaching gear 2
  12. Brake. The car will reach standstill without ever shifting back to first gear.

Hi peterfaj,

I was able to reproduce this error and have entered a bug report, UE-26649, to be assessed by the development staff.