A343F Auto Transmission Over Filled

[panama120 Lurker Find all posts View Profile Close panama120]

Has anyone had any experience with an over filled gearbox?

The transmission fluid and filter was replaced at 165,000 km by a recommended shop. A year and 5,000 km later, I checked the oil color and level. Fluid looks good (reddish pink) but the level on the dipstick was about 55 mm above the notch for the upper limit of the HOT range.

The reading was taken with the engine running and after letting her idle for 5+ minutes, and this after about a 10 minute drive beforehand to warm up. While she was idling after the drive, I moved the shifter down & up 3 or 4 times cycling through all the positions and then took the measurements.

This was my first time checking the AFT and I learned what I could beforehand with some google searches and Youtube.

But now after reading a few posts on this forum I am doubting whether I took the measurement at the right temperature. One post I read said the Toyota shop manual covering off the checking and replacement of AFT was 3 - 4 pages long and included checking the voltage on one of the sensors among some other things he couldn't remember.

I am not sure if this was for the same transmission or not. Mine is the 4 speed Auto and the name plate on the driver's side column indicates A343F Transmission with A03A Axle. Model number is KZJ120L - GKPGT.

I could really use some assistance with the correct shop instructions for checking the level, if any one can help.

Cheers,
Wess

[carco Advanced Member Find all posts View Profile Close carco]

Mate you’re fortunate to have a dipstick model, easy job.
Start her up, cycle the gears then put her in P and with engine running check the stick. It will have a cold and hot position.
If it’s still way over,might pay to take it back to whoever did the service.
Overfill of oil isn’t a big drama, so long as it’s oil and not coolant or worse if you’ve been swimming.

[panama120 Lurker Find all posts View Profile Close panama120]

After following the recommendations given by Carco (thanks mate!), I was able to confirm that the transmission level was too high. Also, I checked and couldn't see any mixing of oil and coolant and I haven't been swimming, so all good there.

Needed: Torque setting for the A343F transmission drain plug on a KZJ120L - GKPGT. Could anyone please pass along the required torque value for this?

Background History: I've been doing it tough with the transmission. Went back to the shop that did the initial job two times - first time they didn't remove enough fluid, second time they removed too much (into a pail that didn't look clean) and wanted to dump the fluid back in. So lost confidence in that shop. Then went to the Toyota Dealership 1+ hour drive away, watched through the shop window and it looked like they knew what they were doing. Not so! I checked the fluid level a few weeks later and it was clearly too low (with no signs of any leaks). Second trip to the Dealership and I spent the whole time in the shop with the mechanic and I verified the level was correct.

A week later (after a good drive), I checked the level once again and it was right where it should be. So I thought I was done with this until yesterday morning when I discovered transmission fluid on the floor. I checked thoroughly for the source and it is clearly leaking at the drain plug (and fortunately nowhere else). When in the shop the previous time, I saw the mechanic begin to loosen the drain plug, but then quickly change his mind, retighten the drain bolt, and then proceeded to get a pump to remove some excess fluid after he had overfilled by a little bit.

So now it looks like the drain bolt is not torqued tight enough or maybe the drain washer is scored.

Hoping that someone can help with the torque value for the drain plug, so I can check this first.

Cheers

[Brett1979 Avid PP Poster! Find all posts View Profile Close Brett1979]

Maybe your drain plug was overtightened by someone & stripped the threads, and when this mechanic went to undo it he realised it was just free spinning and not backing out. So he extracted the fluid another way without wasting time & cost on bolt removal & re-tapping the thread. Over tightening the drain bolt is kind of easy to do if they’re the kind of person that makes a lot of mistakes with everything they do. If this is the case you can possibly get it out though & fix it cheaply by wiping it nice & dry, clamp the bolt tight with locking pliers, pull down as you twist hopefully backing the bolt out. If you get the bolt out, clean it up & wrap the thread a few times with “thread tape” then re-insert & don’t do it up tight. Had a mate’s car with exact same issue & we fixed it for the several years he owned it for after. As for torque, I wouldn’t rely on that, just go by feel & don’t use a wrench/ratcheting wrench that’s too big. Nip it up, don’t do it up too tight like you would a brake caliper bolt for example.