Note that my local Toyota service department advised me that they only drain and fill. However, most other references including a local independent transmission shop informed me they always drop the pan, clean the magnets, change the strainer, and exchange all of the fluid when they perform a transmission fluid service.
The reason that Toyota does not exchange all of the fluid is not clear to me. It is my experience that the remaining fluid in the system will quickly contaminate the new fluid if you do not pull the cooler line and get all of the old fluid out..
Use this guide at your own risk! I assume no responsibility for any damage to your vehicle or personal injury as a result of following this guide. Any comments to improve the procedure will be gratefully received and incorporated where possible.
Special Tools Required
¼” drive torque wrench, suitable to be set to 48 in.lbs. (NOT ft.lbs) of torque.
It took me 3.5 hours from start to finish, including time to take photos and make notes as well as fill the transmission to the right level and take the car for a test drive. If I had to do it again, I think I could reasonably pare this down to about 2 hours.
Aftermarket transmission gasket & strainer $24.85 taxes included (Partsource no. FK-372)
6 liters of automatic transmission fluid T-IV $49.43 taxes included (Toyota Part No. C0BBB-000T4-OL). I bought a case of 12 and received “trade” price from my local dealer = $8.23/liter (taxes included).
Total = $74.28 CDN (taxes included).
Note: For comparison, my local independent transmission shop charges $223.74 (taxes included) for this service, but does not use Toyota T-IV fluid. They use an International Lubricants CAM2 product, a transmission fluid with friction modifier – similar to the T-IV spec.
Let’s get started!
1. Before starting, mark a 1 gallon clear jug (ie. water bottle, windshield washer jug, etc.) in 0.5 liter (16 oz) increments as shown below. This will make it handy to see how much fluid you have drained out of your transmission so that you know how much needs to be added later on. I filled the jug with water using a graduated kitchen beaker to make the marks and then dumped the water.
2. Warm up the engine and transmission by driving the car just before this procedure. Hot transmission fluid is more effective than cold fluid at removing built up sediment. Block the rear tires, set the parking brake, jack up the front of the car and lower it on to jack stands. Note that if you have a floor jack, there is a convenient point (see red arrow above) to jack up the entire front end of the car. Ensure that the car is stable and adequately supported prior to proceeding. Place large amounts of newspaper or cardboard under the car to catch any spills.
3. Remove the transmission fluid dip stick (red circle) and set aside. Place a catch pan under the drain plug (green circle). The drain plug is on the bottom of the transmission pan which is located on driver’s side of the engine compartment. It is accessed by crawling underneath the car from the front. The white stains that you see on the bottom of the transmission pan is from the road salt that spread on the roads here in the winter.
4. Remove the plug (14mm wrench required) and allow the fluid to drain. Warning: Fluid temperatures can exceed 350°F in a hot transmission, so be very careful when draining. Wear protective gloves. Be sure the drain pan is properly centered as the fluid will come out with some force. Draining the transmission pan netted me about 3 1/4 liters of transmission fluid.
5. There are 18 bolts securing the transmission pan to the transmission. Strategically position a drain pan at the rear of the pan. Remove all of the bolts starting at the rear and working toward the front (10mm socket). Do not remove the front two bolts yet. Hold the pan up with one hand and loosen the remaining two front bolts with your other hand. Then gently tip the pan to allow the fluid to drain. This is where the newspapers or cardboard comes in handy – in case you miss the target! If the pan hasn’t been removed in a long time, it may stick and need to be pried downward with a flat head screwdriver. In my case, the pan dropped as soon as I loosened the front two bolts. This step netted me another ¼ liter of transmission fluid.
6. When the fluid has stopped draining from the transmission pan, remove the last two bolts and lower the transmission pan. Here is what mine looked like. There are two magnets circled in red.
7. Remove the magnets and clean them up with a rag. If there are any metal particles on the magnets, remove them. My magnets and pan were pretty clean. I only had a fine coating of metal filings on the magnets and the bottom of the pan.
8. Remove the gasket. My gasket was still pliable and it came off in one piece. If your gasket is stuck to the pan, use a scraper to remove it. Try not to scratch the pan. Ensure that there is no residual gasket on either the pan or the transmission prior to proceeding to the next step. The instructions in my filter kit indicated that it is NOT recommended to sand or wire brush the gasket surfaces, presumably because it may damage the surface and potentially cause leakage. There was no residue on the transmission flange.
8. Clean the pan with a rag and replace the magnets.
9. Reposition the drain pan over the strainer drain hole (blue arrow). Remove the three strainer retaining bolts (10mm) with one hand while holding the strainer up with the other hand. The green circles are short bolts and the red circle is a long bolt. Make a mental note of which bolts go where. Carefully tip the strainer in order to drain the fluid into the drain pan.
10. Here is what the transmission looks like with the strainer removed.
11. I observed a very small amount of grit on the metal filter cloth (red arrows). Based on the small quantity of grit on my strainer, I could have easily re-used it, but since I already had a new one in the filter kit, I decided to toss the old one.
12. Compare the new strainer with the old one to ensure that they are the same.
13. Install the new strainer. Ensure that the longer bolt goes in the correct position. The recommended torque for the strainer bolts is 96 in.lbs.
14. Install the drain pan. It is not recommended to use gasket adhesive to adhere the gasket to the pan. Some recommend using grease to hold the gasket in place, but I didn’t find it necessary. I simply started a few bolts in each corner and that seemed quite adequate to hold the gasket in place. Some of the bolts protrude through the transmission flange and are exposed to the elements on the top side, and were already starting to corrode, so I applied antiseize compound to each of the bolts prior to insertion. Snug the bolts up by hand using a nut driver.
15. Evenly torque the bolts to 48 in.lbs., NOT 48 ft.lbs! Be careful not to over tighten the bolts, or it may squeeze the gasket out, causing a leak. 48 in.lbs is a very low torque. I used a ¼” torque wrench to do this step. I went around the pan twice just to make sure all bolts were properly torqued. Install the drain plug. Recommended torque for the drain plug is 36 ft.lbs.
16. With the car still jacked up, locate the two transmission cooler lines. Disconnect the fluid return hose from the transmission cooler. On my Corolla, the return hose was the one on the driver side (red arrow). If you are not sure which one is the correct hose, disconnect one of them and get a helper to momentarily start the car. With the car running, you want the hose from the cooler with fluid coming out.
I found it easier to access the cooler line from below, so I worked from under the car. The hose can be difficult to get off the metal cooler line. Once the hose clamp is moved down, you need to grasp the hose firmly and twist it to break the friction. If you can twist it, it will slide off easily. If can’t twist it, is my experience that it will not come off, no matter how hard you pull it. I found it easier to twist with a glove on. With a glove, you get a better grip and didn’t have to worry about skinning your knuckles.
17. A small amount of transmission fluid will leak from the hose – not much. Insert a nipple into the transmission hose and connect a clear PVC hose to run to your collection container. Note that transmission cooler line is 5/16” (8mm) ID. I didn’t have the right sized hoses, so I had to improvise. The above photo is taken looking up from ground level.
18. Lower the vehicle so that it is level. With the engine off, add 4 liters of clean transmission fluid to the transmission through the dipstick hole.
18. Get a helper to start the engine and pump 1 liter of old transmission fluid out into the clear collection container. This is where the marks on the container come in handy. Shut off the engine when 1 liter is pumped out. Add one liter of fresh fluid down the dipstick hole.
Note that the fluid doesn’t come out very fast. It is very gentle – maybe one liter every 20-25 seconds. Continue replacing the old and adding the fresh until the fluid coming out of the transmission cooler into the bottle is a nice cherry red, like the new fluid. On mine, I only had to replace 2 liters in addition to the 4 liters I originally added, for a total of 6 liters. This surprised me because on my Camry, it took about 3 + 6 liters for a total of 9 liters to get all of the old pumped out.
19. Replace the transmission cooler return line and securely clamp it in place. I used a gear type clamp so that I will know which line to use for future transmission fluid exchanges. Start the engine and shift the selector into all positions from P to L, then shift into P and apply the parking brake. Check under the car to ensure that there are no leaks.
20. With the engine idling, check the fluid level on the dipstick. Add fluid up to the “cool” level on the dipstick. Replace the dipstick. Over the next several days, re-check the level and adjust if necessary. CAUTION: Do not overfill the transmission as this may cause the fluid to foam and not lubricate properly.
21. Dispose of the old transmission fluid in an environmentally responsible way. In our city, they will take the old transmission fluid free at the hazardous waste disposal depot or will collect it with the recycle goods if it is placed in the original containers. It might also be possible to drop it off at a local garage or transmission shop, or auto parts store.