Subaru TR690 transmission stalling in a 2015 Outback

[D60]

I'm working on this '15 Outback 3.6R with the TR690. 97k miles on odo

It had the transmission front cover leak and was definitely low on fluid. It was making the occasional weird sucking/gurgling noise, a tiny bit of "whirring grinding" and delayed gear engagement when going into D or R (sometimes).

It was also shuddering/lurching from a stop and would occasionally stall at a stop. However for the most part it drove normally and I never felt it was slipping per se.

The more I read on these, the torque converters can cause the stalling, and I believe Mr Subaru has a vid on how to ID the numbers on the converter.

So, here's the question: if the converter is not in the affected numbers, is it likely ok? Can a TR690 cause a stall due to low fluid?

My problem in this case is so many variables, specifically low fluid and the accompanying symptoms. In hindsight I maybe should have added fluid and to see what symptoms -- if any -- existed at proper fluid level. I didn't realize the converters were known to cause a stall until I was already into it

@Trav @The Critic @clinebarger

 

[JavierH19]

Doesn't the tc clutch solenoid do this on almost any automatic if it fails and gets stuck open locking it? Maybe try the solenoid? someone that knows more about autos will likely chime in.

 

[Trav]

I'm working on this '15 Outback 3.6R with the TR690. 97k miles on odo

It had the transmission front cover leak and was definitely low on fluid. It was making the occasional weird sucking/gurgling noise, a tiny bit of "whirring grinding" and delayed gear engagement when going into D or R (sometimes).

It was also shuddering/lurching from a stop and would occasionally stall at a stop. However for the most part it drove normally and I never felt it was slipping per se.

The more I read on these, the torque converters can cause the stalling, and I believe Mr Subaru has a vid on how to ID the numbers on the converter.

So, here's the question: if the converter is not in the affected numbers, is it likely ok? Can a TR690 cause a stall due to low fluid?

My problem in this case is so many variables, specifically low fluid and the accompanying symptoms. In hindsight I maybe should have added fluid and to see what symptoms -- if any -- existed at proper fluid level. I didn't realize the converters were known to cause a stall until I was already into it

@Trav @The Critic @clinebarger

Any transmission codes? Is this applicable to the one you are working on?

https://static.nhtsa.gov/odi/tsbs/2016/MC-10111091-9999.pdf

 

[D60]

So, according to 16-90-13R Subaru seems confident that all torque converters after 10/1/13 were the "countermeasure" units, ie fixed.

Being that this is a '15 MY I guess it's not affected by the known defective converters

 

[D60]

Any transmission codes? Is this applicable to the one you are working on?

https://static.nhtsa.gov/odi/tsbs/2016/MC-10111091-9999.pdf

Good question! Oddly there was no CEL and no typical panic of ABS/TC etc lights. There was only a code for engine stall -- I don't recall the number

 

[nascarnation]

The CVT with chain & pulleys is less fault tolerant to things like low fluid/aeration leading to slippage than conventional planetary units.
If it's not the converter as described previously, there could be other issues internally.
I'm not personally familiar with these but the "I Do Cars" YT has a teardown where he pulls the pan and it has a nice magnet near the filter inlet and if that's covered with shrapnel there's trouble farther inside.

 

[D60]

The CVT with chain & pulleys is less fault tolerant to things like low fluid/aeration leading to slippage than conventional planetary units.
If it's not the converter as described previously, there could be other issues internally.
I'm not personally familiar with these but the "I Do Cars" YT has a teardown where he pulls the pan and it has a nice magnet near the filter inlet and if that's covered with shrapnel there's trouble farther inside.

Yeah agreed. It was a typical female driver situation where she knew something wasn't right but money's tight, blah blah. It wasn't until the stalling that she really stopped driving it....I think there's some adage about squeaky wheels and grease

But YES, in hindsight looking for shrapnel in the pan mighta been smart -- thus why it never occurred to me.

 

[Trav]

Good question! Oddly there was no CEL and no typical panic of ABS/TC etc lights. There was only a code for engine stall -- I don't recall the number

That code will show up again, it would be good info. It could be something as simple as an EGR sticking open slightly when letting off the throttle, common enough on the EJ.

 

[The Critic]

Good question! Oddly there was no CEL and no typical panic of ABS/TC etc lights. There was only a code for engine stall -- I don't recall the number

I've had the weirdest stalling and delayed acceleration issues on Subaru FB's with a dirty throttle body. I know yours is a 3.6, but it might be worth a quick check.

 

[D60]

So once filled to the proper level it was arguably worse than when it first came to me. No stalling (yet?), but cyclical jumps from ~1500 to ~2200 on the highway, significant judder from a stop, and P0300 galore.

For now I'm ignoring the latter because I think/hope it's a symptom of the sudden and unpredictable RPM jumps. The "roughness monitor" (apparently this is Subaru speak for misfire counts?) is all over the map on all 6 cylinders -- so again, I'm setting this aside until the transmissionmission performs better.

Unfortunately, no transmissionmission codes at all.

I dropped the pan, getting to use for the first time ever the gasket cutter @Trav recommended. I wanted to mutter some stuff in German so I could really pretend to be Trav, but alas I don't really know any German....

The pan wasn't great but I'm not sure this is apocalyptic? Sure the magnet's fuzzy but more concerning is the pile of grit at arrow. It was almost a perfect rectangle the shape of the filter pickup, but it flowed a bit when I tipped the pan. I'm assuming it's non-ferrous but at least the filter was obviously not letting it back through.

I dropped the valve body to get a better look at solenoids (but in truth you can test at the connector without removing the vb). Here again some of the grit on top of the vb ain't great:

Sadly, the lockup solenoid tests fine, but since I'm this far I'm installing the Dorman one anyway. Parts cannon? Yeah, I'd say so [heavy sigh]. Actually all the solenoids test within range based on a handy chart I found.

Anyway, the solenoid is the last Hail Mary before I pronounce the entire unit irreparably damaged from being run low on fluid too long. The list of potential symptoms of a failed lockup solenoid includes basically everything the transmission is doing, but I knew the lack of a transmissionmission code was not a good sign that it may be the culprit.

Test drive later today.....and I'm toying with trying anaerobic to seal the pan

 

[D60]

Ok with the Dorman solenoid installed the transmission now won't relearn. I did get it to relearn once previously, but it seemed to take longer than usual. My belief is that I just got lucky the first time and it's not the fault of the Dorman solenoid.

I took it for a test drive anyway and performance is basically unchanged = terrible.

Anyone know the best source for a TR690?

 

[Trav]

Anaerobic is best on solid type mating's not so much for a stamped pan. Unfortunately if they do not offer a gasket you are stuck with the horror aka rtv.

 

[D60]

Anaerobic is best got solid type mating's not so much for a stamped pan. Unfortunately if they do not offer a gasket you are stuck with the horror aka rtv.

I had an open can of Right Stuff I wanted to use up anyway. So, black Right Stuff it was. I will say the "aerosol" action sure makes it easy to apply a consistent bead