So I drained a little transmission fluid... (1 Viewer)

[SnoopisTDI]

I'm an idiot and pulled the wrong drain plug while starting my oil change on my 2004 gx470. I thought the plug felt a little different coming out, now I know why! Drained about 1.5L.

I really wasn't planning on doing full trans flush today. And I can't find a thread for basic drain and fill.

So, two questions. First, did I already mess up by skipping any steps? Second, where is the DIY for getting this thing topped up?

 

[SnoopisTDI]

I've seen various pictures of where the fill plug is supposed to be but can't find it, even just feeling around blindly. Is right by the O2 sensor above the cat, but covered with a heat shield?

 

[captainva]

If you don't have an 03 you don't have a fill plug on your transmission and will need to fill from the trans cooler

 

[SnoopisTDI]

Thanks! I keep finding posts from different years and even different vehicles so I'm getting them mixed up.

 

[Rednexus]

It's a 24 mm hex plug on the very back passenger side of the transmission. You will need to get a pump and slowly fill it in there. Add around 2L of fluid then remove the level plug (5 mm hex plug on the bottom of transmission pan) once the transmission has reached 105F (use an OBDII reader and Torque Pro to determine that, or measure the temp of the pan with an IR thermometer). Let fluid drain out the level plug until it stops, then reinstall it. If no fluid drains out, you'll need to add more through the 24 mm fill plug on the rear of the transmission until it starts draining out. The level plug leads to a tube, and the top of the tube is set at the proper level for the transmission fluid. All of this needs to be done with the GX sitting totally flat on flat ground, or you won't get the right amount of fluid in.

FYI I have used Valvoline MaxLife ATF with success in my GX.

 

[captainva]

Add more fluid with the car off then repeat the process until it gets back up to 105°F

 

[Toyoland66]

It's a 24 mm hex plug on the very back passenger side of the transmission. You will need to get a pump and slowly fill it in there. Add around 2L of fluid then remove the level plug (5 mm hex plug on the bottom of transmission pan) once the transmission has reached 105F (use an OBDII reader and Torque Pro to determine that, or measure the temp of the pan with an IR thermometer). Let fluid drain out the level plug until it stops, then reinstall it. If no fluid drains out, you'll need to add more through the 24 mm fill plug on the rear of the transmission until it starts draining out. The level plug leads to a tube, and the top of the tube is set at the proper level for the transmission fluid. All of this needs to be done with the GX sitting totally flat on flat ground, or you won't get the right amount of fluid in.

FYI I have used Valvoline MaxLife ATF with success in my GX.

Just want to add that the process of draining via the overflow is done with the engine running.

 

[Rednexus]

Just want to add that the process of draining via the overflow is done with the engine running.

Correct! Forgot to clarify that

 

[Rednexus]

Add more fluid with the car off then repeat the process until it gets back up to 105°F

FYI I typically add it with the GX running and have not had many issues. But that is when I have a trans that is 90% full and am adding just enough to get it to overflow at the fill plug (so the temp doesn't really drop since the amount of fluid added is low).

 

[SnoopisTDI]

Thanks all! I found the 24mm fill plug at the rear passenger side of the transmission, added just shy of 2qts, let it warm up to 105degF per IR thermometer measuring of the pan, then with the engine running I removed the check plug which drained out almost half a quart as expected.

Now once it cools down a bit, I can get back to my oil change.

 

[Balrog]

To clarify, one adds room temperature fluid wait till transmission temperature returns to 105F?
I'm getting ready to do a measured 1-gallon exchange from the transmission cooler hoses.

 

[Rednexus]

To clarify, one adds room temperature fluid wait till transmission temperature returns to 105F?
I'm getting ready to do a measured 1-gallon exchange from the transmission cooler hoses.

Do the exchange, gallon-for-gallon, add in a little bit extra, and then do the level check at the very end once the transmission has reached 105F. You'll never be able to get it exact with the exchange, but should be able to get it pretty close. Last time I did it it was cold and I had to add in a full extra quart to get it to flow out through the level check hole.

It's a pain to add it in through the plug at the rear of the transmission if it doesn't flow out through the level check hole, so I'd suggest adding the extra in through the cooler hoses.

 

[Balrog]

Do the exchange, gallon-for-gallon, add in a little bit extra, and then do the level check at the very end once the transmission has reached 105F. You'll never be able to get it exact with the exchange, but should be able to get it pretty close. Last time I did it it was cold and I had to add in a full extra quart to get it to flow out through the level check hole.

It's a pain to add it in through the plug at the rear of the transmission if it doesn't flow out through the level check hole, so I'd suggest adding the extra in through the cooler hoses.

Thanks for writing.
Hm. Any chance that you were low on fluid before you began?
All I bought was a gallon. Sounds like I might want to drain less than a gallon and go from there.

 

[Rednexus]

Thanks for writing.
Hm. Any chance that you were low on fluid before you began?
All I bought was a gallon. Sounds like I might want to drain less than a gallon and go from there.

I did not check so I certainly could have been! I did a pan drop and filter change, but didn't measure how much came out of the pan.

FYI, if you are already doing 1 gallon, it's not that much more work to do all 4 and get totally new fluid. Wal-Mart usually has MaxLife ATF the cheapest.

 

[Balrog]

Wal-Mart usually has MaxLife ATF

lol... I'm cheaper than I am lazy.

 

[Balrog]

I did not check so I certainly could have been! I did a pan drop and filter change, but didn't measure how much came out of the pan.

FYI, if you are already doing 1 gallon, it's not that much more work to do all 4 and get totally new fluid. Wal-Mart usually has MaxLife ATF the cheapest.

...doing all 4.... wait.... wut? OH... 4 quarts/liters~! Yeah. I'm having a bit of difficulty thinking in the long term with some recent health issues.

 

[Rednexus]

A full fluid exchange is 15 quarts or just under 4 gallons. Not necessary of your fluid is fairly clean but a good idea if it us older and dark.

 

[Balrog]

A full fluid exchange is 15 quarts or just under 4 gallons. Not necessary of your fluid is fairly clean but a good idea if it us older and dark.

Do you have a source for that figure?

 

[Rednexus]

Do you have a source for that figure?

Not off the top of my head. That's what i needed before i saw fresh fluid at the cooler lines.

 

[Balrog]

Not off the top of my head. That's what i needed before i saw fresh fluid at the cooler lines.

The amount required is probably related to condition & previous maintenance. I've seen other figures for operating temperature range. When I get a chance, I'm going to see if I can find a trans. temp readout on my Autel AL619. So far google has yielded nothing. Might have to get a specialized doodad.