Yep, the rear pump check valve and spring has caused many governor gears to fail. MB has a kit to eliminate the rear pump and check valve. If you do not have a pressure gauge you easily diagnose the governor by removing its cover and if you can turn the governor by hand, the gear is bad If not the B1 servo has a leak. Other possibilities are 1-2 shift valve or 1-2 feed control valve; valve body.