How to Drain/Refill Automatic Transmission

Hey Joey! I received my glorified paper clip last week. It works like a champion!

 

So I just finished up my transmissions fluid flush today after having to replace the metal cooler lines in the fron of the truck frame due to salt and corrosion. I also dropped the pan, cleaned it and replaced the magnets with super magnets, and installed a new filter as well. Flushed out the old fluid with Vavoline Maxlife. After finally getting it all back together, I started the temperature check sequence. It was 35 degrees outside, and it took over 40 mins to warm up to temp. Just an FYI.

Also, I bought a scangauge to check the temperature with. When I finished the fluid level temp check sequence, i restarted the gruck, and I plugged in the scangauge again and it only read 93 degrees F. Makes me wonder which method is more accurate...I imagine the onboard diagnostics are better than the aftermarket ones. The proper temp range is 115-130 right?

 

Mine would check at 97-115°F.

 

Next time (assuming you did not do it this time) block the airflow going through the transmission cooler.

Being parked, there isn't much airflow, but every little bit helps.

 

Clayton~

As per Mountain Lion's and Fortech's excellent write ups and as per the OEM manual, the following applies:

6. FLUID LEVEL CHECK NOTICE: The fluid temperature must be between 46°C (115°F) and 56°C (130°F) to accurately check the fluid level.

Like you, I also did the drop pan (Fortech) and the full flush combo (Mountain Lion). Those two excellent write ups showed me how to change transmission fluid with out any problem. I used "Wit's End" OBD diagnostic port jumper wire to check temperature by default, because the BAFX Bluetooth scanner paired with the Pro Torque app would not give me transmission temperature reading. My truck is a 2012 Tacoma with the A750E transmission. After reading your post regarding temperature discrepancies, I'm glad I used the jumper method.

On a related note, after I did the full transmission flush the infamous and mysterious driveline clunk/thunk coming from my driveshaft immediately went away. Has anyone heard of this and how the flush was a fix? I remember reading a post that another TW member had the same experience. Any feed back would be appreciated.

 

I have the same setup for checking tranny temp. There are PID's that you have to put in via the Torque app. I have a 2012 and it works for me. Check it out here. https://www.tacomaworld.com/threads/custom-pids-for-torque-pro-app.438689/

I was never able to get my tranny oil warm enough to get the light to illuminate. My transmission temp still barely gets above 100 and even after driving 11-12 miles including a few hills, the highest it's gone is 113 that I've seen. That's the converter temp too. I'm guessing that will change when we warm up for Spring if that ever comes.

 

Jburner~

Thanks for that information. I'm glad I did not return OBD to BAFX seller. I'm curious, when I contacted BAFX on the phone the representative did not inform about inputting custom PID. BAFX did give me an appreciated $5.00 credit refund on my cost of scanner on Amazon. I'm eager to try and plug in parameter. I read the the attached custom PID post with formulas. How do I specifically enter the custom PID in the Torque app? It's clear as mud to me. Your information as to how you did it would be helpful and appreciated. Thanks in advance!

 

On my 4th and final DAF, it was about 13° out. It took a good hour of idle time for the light to come on.

 

Torque Settings working for 2012 Tacoma

1.Op Torque App
2. Settings (Select gear bottom left)
3. Settings (on popup)
3. Manage extra PID's
4. 3 dots in top right - "add custom PID"
5. Input these settings (anything that does not have input defined, leave "as is")


OBD2 Mode and PID:
2182
Long Name:
Transmission Fluid Temperature 1
Short Name:
ttemp1
Minimum Value:
0.0
Maximum value:
300.0
Scale factor:
x1
Unit Type:
°F
Equation:
((((A*256)+B) * (7/100) – 400)/10)

OBD2 Mode and PID:
2182
Long Name:
Transmission Fluid Temperature 2
Short Name:
ttemp2
Minimum Value:
0.0
Maximum value:
300.0
Scale factor:
x1
Unit Type:
°F
Equation:
((((C*256)+D) * (7/100) – 400)/10)

 

jburner~

WOW! I followed your instructions and it worked without a hitch. Do you know whether I need both ttemp1 and ttemp 2? Are the ttemps1&2 for temperature readings at different parts of the transmission? They each give different temperature readings. Thanks again, Sir!

BTW, the ttemp2 equation above requires a closed parenthesis at the end. ProTorque app will tell you when you try an enter the equation without the closed parenthesis. I am sure it was a typo.

 

Glad to hear it worked. Temp 1 is the Pan temp, Temp 2 is the Converter Outlet. I changed the short names to those titles so I know what's what.

Yes they fluctuate and eventually the pan temp is brought up to where the converter temp is. The converter varies the most.

Good catch on the ), I made the change. It didn't copy and paste over. I did that on my phone, little difficult to see!

 

My dump ass will just stick with my OBD contraption .

 

2012 Tacoma prerunner. Trans light stays on after doing the shift cycle back to park. Anybody else seen this? Have ran through the cycle a million times. Never seen this before...about to put my scan gauge from another truck on

 

Was the truck recently driven and what's the outside air temp?

 

About 60 degrees farenheit in the shop. Yes, I had ran it through the gears to move fluid through the trans. Never thought the trans would stay within the check range, even after letting it cool for 1hr+ before trying trans a/t temp check mode repeatedly. I finally let it run with the trans temp light on for kicks. After 15mins of running it began flashing...so this whole time it was going right into check mode (trans was at temp). Hard to believe the whole time it never cooled down. Going to re check this morning from completely cool and double check fluid level. I've always done it with a scan gauge or ultra gauge. Will be purchasing one for this truck (work vehicle, not my personal). Will update once confirmed this evening

 

Update- Added 1/2qt before re-checking. Went back into trans temp mode from cold start. Still never got the trans light returning back to park for 2 seconds. Still allowed it to idle until the temp light illuminated. Immediately pulled check bolt and got a few ounces. Let the truck idle until I got the flashing trans temp to further confirm it was in temp check mode. All seems well, not sure if this is something different with the 2012-2015

 

I've done several checks on my transmission and never got the light after returning to park either. '15 Prerunner

 

Good to know

 

NCtaco914~

A week ago, I completed the drop pan/change filter and full fluid flush on my 2012 Tacoma with the A750E transmission. My own experience with the temp check procedure was exactly like you described. After entering temperature check mode (shifting sequence from Neutral to Drive), I also did not see the temperature light for 2 seconds when returning to Park. I proceeded to check fluid level like you did and had a few ounces of overflow. I also let my truck idle until temperature light began to flash indicating temperature above 130 F. I am confirming your temperature check experience on my 2012 Tacoma w/ A750E transmission.

One week later, I can tell you that the fluid flush was a huge positive improvement on my transmission e.g. smoother operation. I had the infamous "thunk/clunk" issue on letting off the brake that is reported by other TW members. As a pleasing surprise, the annoying thunk/clunk is now gone/fixed!!!! My transmission fluid must have been low. I still don't understand how transmission fluid change was a fix for the thunk/clunk issue. Any input on that from TW would be appreciated. Thanks.

 

I knew my tranny fluid was low because I accidentally pulled the plug when performing an oil chance on two seperate occasions. I noticed a slight hesitation when accelerating from a stop and shifting was a little harsh. Thanks to this thread I was able to drain, fill and set proper tranny fluid level today. Smoother shifting now. Thanks for posting!