Simple procedure for Transmission Flush

A year ago on July 9, 2008, I posted a lengthy tutorial on performing an ATF drain and fill. Actually, the Amsoil tutorial also incorporated a transmission pan drop and ATF
filter/screen/strainer replacement but that's very risky and really unnecessary with the Camry, as Ray pointed out at the time. There was lots of good info in that thread, thanks to Ray O's and John G. Dole's contributions, among others. The posts were in a thread titled "ATF, ATF filter, and ATF pan gasket Change Procedure." Some info from the 5th Generation Camry manual was also included.
Today, as I get closer to changing my own ATF fluid for the first time ever, I'm posting another tutorial. This one is for a simple, do-it-yourself procedure for flushing your car's ATF at home without use of the potentially dangerous flushing machines used by some shops.
I'll probably just do a simple drain-and-fill, not a flush, for my first ATF change, but if I ever decide to do a flush, here are the steps:
(By the way, a drain and fill will replace only part of the ATF fluid since 50 to 60 percent of the ATF will be in the torque converter, not in the transmission pan.)
================================= I found 2 similar procedures for a trans flush at Here are the links: 1381 30
And here is a copy of the procedure from the first link above, in case the post ever disappears from .
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Question: How can I flush my transmission fluid without bringing it to a shop?
You can actually change virtually all the fluid in the system using the following method. We have 5 Toyota's in the family, and I have done this to them all at least once.
It takes about an hour. Use whatever fluid is recommended on the dipstick, or in the manual. Our Camry's and Corolla's take Dexron, but the Celica takes Toyota Type IV fluid, available only from Toyota, at about $3.50/qt. Use what's recommended, or you'll be sorry. It's still less expensive than having it done.
1. Drop the pan*, drain the fluid, replace the filter, and reinstall the pan as you usually do. 2. Add 3 quarts of fluid. (or however many quarts of fluid are drained from the pan). 3. Remove the fluid return line at the transmission (usually the upper of the two lines), and place it into a one-gallon milk jug or similar semi-transparent container. You may want to place the container in a box with rags around it so that it doesn't spill. 4. Start the engine, and let about a quart or so of fluid get pumped into the milk jug (about 10-15 seconds). 5. Stop the engine, and add a quart of fluid to the transmission. 6. Repeat steps 4 and 5 until you get new fluid out of the drain line. You'll use about 8-10 quarts of fluid total, including the 3 you put in at the beginning, so you may need more than one milk jug. 7. Reinstall the drain line to the transmission, start the engine, and check for leaks. 8. With your foot on the brake, put the transmission in each gear, then into Park. 9.Let the car down and check the fluid level on the dipstick. Add fluid if needed to bring it up to the proper level. 10. Take it out for a test drive, and check the fluid level again.
(*One caveat is that it is not nessary to drop the pan. Removing and replacing the filter is not necessary. It is more or less just a screen that doesn't get plugged unless your clutch plates shread or something equally traumatic happens. Brian R.)
=================================== [Now here is a copy of another simple flush procedure, from the second ToyotaNation link above. The two procedures are very similar. By the way, sorry for the lengthy post, but I always have to learn as much as I can about a procedure before I attempt it for the first time :-)
The following was written by "Kocho" on 10/13/2003:]
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Can someone comment if I did this right?
Old post... Anyways: Yes - mine does the same (2000 LE, 4 cyl). At about 25K miles, it turned pretty dark, plus it looked thicker than the new fluid. I drained, refilled with Mobil 1 Synthetic ATF at about 25K, then again at about 50K. The second time it looked somewhat better, bit still dirty and dark. First time I had quite a few metal shavings, second time - very few small ones.
Both times I drained and refilled the differential fluid as well. The second time it looked almost like new, unlike the first time where it was about as dirty as the tranny fluid with shavings in it.
=== Now, here's what I did today - can someone comment if anything was not done right and if you think I got all the dirty fluid out?
A home-made tranny "flush": (1) Lifted the car. Removed the metal plate under the radiator (not necessary to get access, but it would get dirty otherwise)
(2) Disconnected the ATF rubber lines TO and FROM the radiator. Attached two pieces of about 3 feet each of a clear 3/8 " (10 mm) INTERNAL diameter hose to the metal pipes in place of the original rubber hoses. Put the other end of the hoses in a large jug to hold the dirty fluid.
Now at this point I was hoping that if I put one of the houses (the driver side one) in a jug with clean fluid, the car will do the job for me - someone on the Internet (the old I think) said that the pump will pump out dirty fluid on one end and suck in clean fluid on the other.
Not so. It only pumps out the old fluid and does not suck in new fluid.
So step (2) should only require to disconnect the passenger-side hose.
The car not being able to suck-in fluid on its own through the driver side hose makes the procedure longer as you need to pour in the fresh fluid by hand if you do not have a pump to do it for you...
(3) Start the engine briefly - the tranny pump will pump-out the fluid at a rate of about 1 quart every 15 seconds or so. Wait till about 1.5 quarts of dirty fluid comes out. Do not wait longer because apparently the pump starts to suck in some air inside the tranny and the fluid starts to foam. Not sure if this is bad, but I did not want to risk it. So shut it down after about 1/3 of a galon gets out.
The old fluid was pretty dark with some burned smell, but not too strong. Still, I think it was time to replace, since now at 76K miles ( 3/4 highway) there was probably more than half of the original factory ATF still in there (the two previous drains and refills only got out some of it...)
(4) Put in (through the dipstick/refill opening) about as much new fluid as you drained from the old one.
(5) Repeat steps (3) and (4) till the fluid coming out starts to look clean.
It took me about 10 quarts of clean oil to flush the old oil out.
(6) Just to be on the safe side, I also drained the fluid from the pan under the car at this point. It came out pretty clean (although not as fresh as the new fluid, but pretty close.
Notably, this time I had no metal shavings at all on the drain plug. I guess the Mobil 1 Synthetic ATF does a godd job (or just the tranny has no more shavings to shed anyways).
Put back the plug back on, torqued at 36 lb/ft and filled-in 2 quarts of fresh fluid to compensate for this draining.
(7) Reattached the radiator hose and cleaned-up the mess
(8) Started the car and checked the fluid level. It was in the middle between the hot and cold marks.
At this point I shloud have driven the car till it warms-up (about 3-5 miles) and checked the fluid, expecting to find it within the "hot" range. Since it was getting late, I postponed the fine check for tomorrow, when I'll add some more fluid if necessary.
I used 12 quarts of fresh oil for this ($5 each) plus the $2 for the hose from HomeDepot. Total about $65 with the tax. Plus two hours labor, mostly to setup and clean-up the mess (the actual drain and refill took about an hour).
Will see how it drives tomorrow - hopefully nothing bad will happen from all this synthetic ATF in there. - Kocho.
=======================================[About 6 months later, Mr. Kocho wrote:] ======================================= Home-made flush - follow-up
Just FYI - about 20K miles after the flush - no leaks, no issues (knock on wood)
=============================================[Here's a good point brought up by "JoAndJo":] ============================================= Very nice steps and instructions!! The only difference from my way is I do step (6) before your step (2). This way I can make sure the new fluid is not mixed with the old fluid in the tranny pan. On my '92 V6, I also disconnect the passenger-side cooler line. But when I flushed my friend's 95 Avalon, I noticed the cooler line was reversed. So I had to disconnect the driver-side hose. Just be careful.
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