In this issue of Keep Those Trannys Rolling, we are going to take a look at a low mileage 2017 Volkswagon Jetta equipped with a 1.8L engine and a 09G transmission that was experiencing a “no forward” movement condition at times. This vehicle came to my attention when I received a call from Sean Jones at AAMCO Transmissions in Venice, Florida. Sean called the ATRA Hotline to see if there were any bulletins or information related to an intermittent “no forward” movement condition on a 09G transmission. While I was going through the ATRA Technical Center website with Sean, he commented that this vehicle had been to several other shops, but none of the shops could fix the intermittent “no forward” movement condition. As a last resort, the last shop recommended replacing the transmission with an assembly, but they were unable to locate one and referred the customer to AAMCO Transmissions for diagnosis and possible repair.
Duplicate to Diagnose
While discussing the two ATRA bulletins related to a “no forward” movement concern, Sean indicated that the “no forward” movement concern was intermittent and difficult to duplicate. Sean said that he had checked the computer system for codes and found all forward range ratio codes were present in the Transmission Control Module (TCM). He installed a pressure gauge onto the transmission and drove the vehicle several times. The pressure was within specification each time the transmission had a “no forward” movement condition. Sean checked the solenoid commands at the transmission connector. The solenoid commands were correct when the “no forward” movement concern occurred. 
All indications pointed towards an internal transmission problem. Sean said he then removed the valve body and air-checked each component with 35 psi of regulated air pressure. Each component air checked with no leaks. Sean went through the valve body, checking for worn or sticking valves and excessive bore wear; everything looked good. Sean checked each of the solenoid’s operation. The solenoids seemed to be working properly. With the valve body and solenoids inspected, it was time to remove the transmission from the vehicle and disassemble it for an internal inspection.
Internal Inspection
With the transmission on the bench and before case disassembly, Sean began his inspection by re-air-checking each clutch component, paying close attention to the K1 clutch circuit. All of the clutch components air checked with low pressure. Sean began disassembling the transmission and setting each component aside for later inspection. He removed the Low one-way clutch (low sprag) and inspected it for wear. The Low one-way clutch looked good, with no signs of wear. With the Low oneway clutch out of the way, Sean began checking the individual components, starting with the disassembly and inspection of the B2 brake. The B2 brake clutches were not worn, and the B2 brake piston and seal were in good shape. Sean then moved on to the K2 clutch, where he also found the clutches, piston, and seals in good shape. Then Sean inspected the K3 clutch for wear. The K3 clutches, sealing rings, and piston were all in good shape, with no signs of wear. Sean then inspected the B1 brake for any signs of wear. The B1 brake clutches were like new, and the sealing rings and piston were in good shape. With the Low one-way clutch, B2 brake, K2 clutch, K3 clutch, and B1 brake all in good condition, the only clutch left to inspect was the K1 clutch.
K1 Clutch Drum Concern Identified
With the K1 clutch being the driving element in 1st, 2nd, 3rd, and 4th gears, Sean was confident he would find the problem in the K1 clutch drum. Sean disassembled the K1 drum for inspection. To Sean’s surprise, the K1 clutch components looked good. The K1 clutches were not worn. The piston and seals air checked at low pressure. Sean inspected the K1 clutch drum for cracks or any signs of damage. Everything looked good in the K1 clutch drum (Figure 1). With “NO PROBLEM FOUND,” Sean reassembled the clutch drums and started installing them back into the case. Installing the clutch drums into the case was pretty straightforward until Sean tried installing the K1 clutch drum. As Sean went to install the K1 clutch drum, he noticed that the center hub portion of the K1 clutch drum would momentarily move while trying to align the K1 clutches into the clutch hub. Sean removed the K1 clutch drum for a more detailed inspection. During the K1 clutch drum inspection, holding the outer drum and rotating the center hub (Figures 2 and 3), Sean found that the center hub of the K1 clutch drum separated from the outer drum (Figure 4). 
This was good news. Sean had identified the problem with the K1 clutch drum. Sean replaced the K1 clutch drum with a new K1 clutch drum and continued reassembling the transmission case. After assembling the transmission case, Sean air-checked the components with 35 psi of regulated air pressure and verified that the clutches were applying and releasing properly. Sean rechecked the valve body and solenoids before installing the valve body, filter, and pan onto the case. Sean installed the transmission back into the vehicle and filled the transmission with VW 09G fluid. After starting the vehicle and allowing the transmission to reach normal operating temperature, Sean verified the transmission fluid level and was ready to head out for a test drive.
Final Test Drive
With the K1 clutch drum replacement, Sean was confident he had fixed the “no forward” movement concern, so he headed out for a test drive. Sean drove the vehicle through city streets, parking lots, and the freeway. The transmission worked great. Sean returned to the shop and checked the TCM for codes. 
There were no codes present in the TCM. Sean checked the transmission for leaks; there were none. Sean rechecked the transmission fluid level, and it was right at the proper level. With the “no forward” movement concern fixed, it was time for Sean to contact his customer and deliver the vehicle.
Well, there you have it. By taking a little extra time and performing a detailed inspection of the K1 clutch drum., Sean was able to bring this 09G back to life and keep this tranny rolling down the road.
I would like to take a moment to thank Sean Jones of AAMCO Transmissions in Venice, Florida, for sharing this story with us. Thanks, Sean, keep up the good work.
