2020 Tundra: Drain & fill Trans/Transfer case odd things

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So I've been doing a 60k service on my 2020 and today I did the transfer case and transmission drain and fill. Some strange, but minor, things I thought I'd see what your thoughts are on.

First, the transfer case drain and fill plugs were extremely loose. I mean, I almost could have turned them without a ratchet if I just used the socket and and extension. They were not leaking at all, but they were nowhere near the torque specs. They hadn't even been torqued enough to get into the teflon tape on the plug threads. Just thought that was odd.

Secondly, when I drained the transmission pan for a "drain & fill", I opened the fill hole first and nothing came out, which I expected. When I drained, exactly 3.5 qts came out according to my graduated bucket; that was at pan/shop temp of 90F. When I filled, I only got about 2.75 qts in before it started coming out of the fill hole. I reinstalled the fill plug, heated the trans temp up to 105F, and it trickled out of the check plug like it was at the right level right away. I checked to make sure the truck and the pan were level as well. The only thing I can figure is that my graduated bucket markings may have been off? I drove with the scan gauge for 30 minutes after and the temp was 200 plus or minus and seemed to shift fine. Fluid was Toyota OE WS.
 
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Have seen loose everything on vehicles that left the factory. Our Fleet would take delivery of several hundred vehicles during good budget years. Our new car service prior to issuance was to check all fill and drain plugs. Seen differential plugs that were hanging by one thread. These were specifically fleet orders but still assembled on the same production lines as civilian vehicles with the same factory employees. I’m not surprised at your findings. Engines with fluids low or overfilled, interior components left loose, tires low or pumped up with twice the air pressure. Have seen new cars delivered in on the car carrier with a connecting rod through the block.
 
I’ve had to add fluids to the last 3 new vehicles we’ve purchased. My regimen is to run it in my shop when I get home from the dealer and get my creeper and go end to end checking everything. Let the tires down with my gauge while on the dealer lot. The sad thing is the only fluid Ive found over filled was the motor oil. Last one, transmission was quart and a half low.
 
I just don't see any way it could be coming out of the fill hole unless my hose was up against something in there. I used a slippery pete pump and it has a little spring clip nozzle so you don't jam the hose in too far. It would take way more fluid than that to do that. But, fluid running out of the check plug really baffles me with only 2.75 qts put. Typically I think you should get what I got out by most people's accounts. I'm going to recheck it today and also take a look up in that fill hole with a camera scope I have. Something just isn't right. I planned on putting in 4 qts, heating it up and then draining about a half quart from the check plug. On the positive side, what came out didn't look bad or smell bad, so I guess there's that at least.
 
The bucket probably isn’t THAT inaccurate. Every new Ford truck I’ve checked, the rear axle and transfer case have been low. A bunch of 10r80s have been under filled. It’s not uncommon for stuff to be under or overfilled. Shouldn’t happen,but it does.
 
So I've been doing a 60k service on my 2020 and today I did the transfer case and transmission drain and fill. Some strange, but minor, things I thought I'd see what your thoughts are on.

First, the transfer case drain and fill plugs were extremely loose. I mean, I almost could have turned them without a ratchet if I just used the socket and and extension. They were not leaking at all, but they were nowhere near the torque specs. They hadn't even been torqued enough to get into the teflon tape on the plug threads. Just thought that was odd.

Secondly, when I drained the transmission pan for a "drain & fill", I opened the fill hole first and nothing came out, which I expected. When I drained, exactly 3.5 qts came out according to my graduated bucket; that was at pan/shop temp of 90F. When I filled, I only got about 2.75 qts in before it started coming out of the fill hole. I reinstalled the fill plug, heated the trans temp up to 105F, and it trickled out of the check plug like it was at the right level right away. I checked to make sure the truck and the pan were level as well. The only thing I can figure is that my graduated bucket markings may have been off? I drove with the scan gauge for 30 minutes after and the temp was 200 plus or minus and seemed to shift fine. Fluid was Toyota OE WS.
You didn’t fill it right - so, it’s about 0.75 quarts low. It’ll shift OK - probably…

You have to idle it, heat it up and then, check the level. A dribble is not a good check. A small stream is a good check. Some fluid may have been sloshed into the tube - it has to be a small stream so that you know it is flowing it, not just a bit of trapped fluid.

So, doing in the order you did - not idling first, meant that some of the fluid had drained back into the pan - so your fill was less than you removed. Further, the check temperature is warmer, at 127-138, so, that part wasn’t right, either.

Now, it may have been filled incorrectly at the factory, who knows, but you have to follow the procedure to get the level right.

Fill, idle, warm to the proper temperature, remove the plug and check. Valid check is continuous flow, not a dribble of trapped fluid.
 
The bucket probably isn’t THAT inaccurate. Every new Ford truck I’ve checked, the rear axle and transfer case have been low. A bunch of 10r80s have been under filled. It’s not uncommon for stuff to be under or overfilled. Shouldn’t happen,but it does.
Ram trucks are just as bad.
 
So I've been doing a 60k service on my 2020 and today I did the transfer case and transmission drain and fill. Some strange, but minor, things I thought I'd see what your thoughts are on.

First, the transfer case drain and fill plugs were extremely loose. I mean, I almost could have turned them without a ratchet if I just used the socket and and extension. They were not leaking at all, but they were nowhere near the torque specs. They hadn't even been torqued enough to get into the teflon tape on the plug threads. Just thought that was odd.

Secondly, when I drained the transmission pan for a "drain & fill", I opened the fill hole first and nothing came out, which I expected. When I drained, exactly 3.5 qts came out according to my graduated bucket; that was at pan/shop temp of 90F. When I filled, I only got about 2.75 qts in before it started coming out of the fill hole. I reinstalled the fill plug, heated the trans temp up to 105F, and it trickled out of the check plug like it was at the right level right away. I checked to make sure the truck and the pan were level as well. The only thing I can figure is that my graduated bucket markings may have been off? I drove with the scan gauge for 30 minutes after and the temp was 200 plus or minus and seemed to shift fine. Fluid was Toyota OE WS.
You are supposed to bypass the oil cooler when doing the trans fluid check. What you take out is irrelevant.
 
You didn’t fill it right - so, it’s about 0.75 quarts low. It’ll shift OK - probably…

You have to idle it, heat it up and then, check the level. A dribble is not a good check. A small stream is a good check. Some fluid may have been sloshed into the tube - it has to be a small stream so that you know it is flowing it, not just a bit of trapped fluid.

So, doing in the order you did - not idling first, meant that some of the fluid had drained back into the pan - so your fill was less than you removed. Further, the check temperature is warmer, at 127-138, so, that part wasn’t right, either.

Now, it may have been filled incorrectly at the factory, who knows, but you have to follow the procedure to get the level right.

Fill, idle, warm to the proper temperature, remove the plug and check. Valid check is continuous flow, not a dribble of trapped fluid.
No, I did let it idle to heat the fluid as well as shifting at idle. I'm not sure where you read I didn't heat the fluid prior to checking the level. Maybe you were confused that the initial drain was at ambient temp which was 90. I didn't heat the fluid to drain it. Still I got 3.5 quarts out.
Your information on the check temp is incorrect for my model year. Those temps are for the older model years. My check temp is 99-111F. I rechecked it today after adding a quart and stopped at a pencil lead thick flow which I described as a ""dribble; so my bad for saying "dribble" since that can mean a lot of things to different people. All is good now.

For the AB60F (transmission used with 5.7 V8 4x4), the range is 99F to 111F. This is per Toyota FSM. If the truck has the 4.6 V8 with the A760E/F, the temperature range is 127F to 138F according to the FSM.

1699978852651.png
 
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Teflon tape on transfer case drain plug threads? Whose been in there before? 1 owner?
I am the original owner. No one has touched it for anything except me as far as maintenance. The only time it has been in the shop was for the light wiring recall and a warranty repair for the driver's door stop.
 
No, I did let it idle to heat the fluid as well as shifting at idle. I'm not sure where you read I didn't heat the fluid prior to checking the level. Maybe you were confused that the initial drain was at ambient temp which was 90. I didn't heat the fluid to drain it. Still I got 3.5 quarts out.
Your information on the check temp is incorrect for my model year. Those temps are for the older model years. My check temp is 99-111F. I rechecked it today after adding a quart and stopped at a pencil lead thick flow which I described as a ""dribble; so my bad for saying "dribble" since that can mean a lot of things to different people. All is good now.

For the AB60F (transmission used with 5.7 V8 4x4), the range is 99F to 111F. This is per Toyota FSM. If the truck has the 4.6 V8 with the A760E/F, the temperature range is 127F to 138F according to the FSM.

1699978852651.png
Then, I stand corrected.

The only explanation is the one I offered before - overfilled by the factory.
 
You are supposed to bypass the oil cooler when doing the trans fluid check. What you take out is irrelevant.
Unless you are referring to the puck cooler, you only pin that if you have added a transmission cooler. The 2020 did not have the factory installed trans cooler. It was deleted by Toyota I believe starting in 2020 in their infinite wisdom.
 
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