5EAT Torque Converter not releasing

[RabidWombat]

2009 Legacy GT, 5EAT, 80k miles. Drivetrain is 100% stock, regular maintenance. Transmission fluid was changed at 60k, level is ok.

 

Problem: When stopping in sport mode (S) the engine will sometimes lug and almost stall. Almost like the torque converter is not releasing, although, sometimes it seems like it should have released. This doesn't seem to happen in (I) mode.

 

Only warning light is that the "AT Oil Light Temp" will sometimes flash for a fraction of a second. No ECU codes, no engine lights.

 

Dealer diagnosed and said it needed a new torque converter for about $2500.

 

The problem doesn't really match the most common torque converter failure modes. There's no slip or shudder on start-up. Everything drives and shift smoothly.

 

I performed the Subaru torque converter test procedure and it stalled at about 3k rpm. The recommended range is 2.3k-3.2k rpm.

 

Looking at the factory service manual, nothing in the manual points to the torque converter. Solenoids are a potential problem, but those seem much easier to access.

 

How to go about diagnosing this, given that I don't have any shop, and basically have to rely on a mechanic.

 

Second issue, there don't seem to be many mechanics familiar with the 5EAT so I'm basically looking at the dealers.

 

I'm in the Falls Church/Alexandria, VA area, if anyone knows an independent shop they actually trust. I've tried two so far, and come up empty.

[m sprank]

Solenoids are part of the valve body pack. You can get a VB new for about $700. But, I have never seen one fail without giving at least a TCM code.

[apexi]

I'm not sure what shops you've tried, but you may want to contact Mach V motorsports in Sterling. I have no experience with them, I only know they've been around for a long time and are worth a shot. If they don't do that kind of work, maybe they could help refer to you a trusted shop that does.

 

https://www.fastwrx.com/

https://machv.com/