I’ve been scanning the forum for a while now and can’t find anyone who is reported this issue if anyone knows of a thread that can be helpful let me know and I’ll delete this.


I have a 2012 SR5 fifth GEN 182,362 miles and yesterday I made a U-turn and lost all torque to my wheels. As I made a U-turn I heard a clink right before I lost the torque. I can shift gears fine and my dash knows which Gear I am in as a displays the correct gear. I can shift transfer case positions fine as well but in any case no torque is provided to the wheels. I think this rules out CVS. I also did a visual inspection of my drive shafts and there is no play or abnormalities in my you joints or my shafts. It is not stuck in park and when it’s in park wheels will not turn when pushed or pulled which rules out it being stuck in park. I recently did a transmission fluid exchange and a normal flush via the ATF return line. Are used all Toyota OEM parts and Toyota ATFWS. I followed all the procedures that are recommended for an ATF flush. I filled 11.9 quarts and brought transmission to temp via jumperring The OBD two ports and pulling the check plug to drain the excess. Since then I have noticed a great improvement in the transmission even though the fluid was only nominally dirty when examined. No exceptionally large chunks of metal were observed in the old fluid.

I suspect this issue could be my torque converter and I dropped it off at Toyota for a diagnostic but I figured I’d also ask here to see if anybody has any idea or has maybe experienced this as well. I look forward to anyone who wants to help’s response.

Bump

If it's already at Toyota let's just wait and see their diagnosis.

no the forum members will know what it is vs the dealership (stealership) cant be trusted



just the let dealership figure it out

Sick! Thanks Dude!

I would guess maybe the transfer case broke. Was the fluid changed regularly? You were in 2WD when this happened?

I drained and filled rear diff And checked T case and front diff both were nowhere close to needing to be changed. Yes I was in 2H on blacktop when this happened. I would be really surprised if the transfer case is part of the problem 4H and 4L both seem to be engaging with no problem aside from the throttle not transferring torque in any gear.

Does your engine respond to throttle input, does it rev up but no vehicle movement?

Curious to see what they diagnose. That's a bit disconcerting to hear about at 180k. Would have thought there would be some kind of warning signs for a while before hand if it was the transmission. Even with zero diff/tc fluid changes I wouldn't really expect that at 180k unless you tow or offroad. You got a wife or kid or someone that might have drove around in 4hi on dry pavement a bunch without realizing?

Hopefully it's nothing too expensive but it sounds like you heard something snap.

Yes RPMs respond to throttle input but no turning of wheels

No it’s just me the only driver and never in 4WD unless off-road. I am Heavy though RTT steel skids decked system awning etc. so I think I’d be safe to say I am hauling weight all the time.

Without inspecting the vehicle, it sounds like it could be a broken flexplate.

You would hear that surely and it would still drive with a cracked flex plate. Seems more like rear diff (especially if he was doing a u-turn, and he would need to unbolt rear shaft to get power at front diff I think), transfer case, torque converter or something like that.

I'm thinking low trans fluid.

My guess would be either a sensor issue or transmission solenoids aren't shifting correctly for some reason. Or it's low or out of fluid. Like that transmission cooler line used for a flush came off and dumped the fluid out or something.

Or - given the age, did you check the coolant for a pink milkshake? Could have lost the trans fluid into the radiator.

Rear diff issues would still be drivable or at least moveable in 4hi and it wouldn't lock up the tires in park. When you put in park the rear parking pawl engages the transmission output shaft. The fact that that locks up the drivetrain downstream from there tells me the issue is between there and the engine.

I don't know how you'd diagnose the transmission beyond that without pulling something apart or having a diagnostic software.

The torque converter is a fluid coupling that very rarely would wear out or break to the point where it wouldn't move the vehicle or give at least some forward motion. Unless a catastrophic internal seal blew out or something.

Taking a random guess that you should put no value on - My guess is some solenoid is not functioning or the transmission oil pump line pressure regulator is bad or something like that that's not engaging the clutches. The ECU is designed with failsafe systems that work around almost any individual solenoid failure to make sure it will still drive. So maybe that doesn't fit. Hard to know much more without better info from diagnostic checks.