Automatic Transmission flush service explained
By: PCH
April 7th, 2012
11:21 pm
With slightly over 80K miles on the odometer, it was definitely the time to replace the fluid in the automatic transmission. Since a quick drain and fill only changes half of all fluids, a more involved procedure is recommended: the transmission flush.
It is performed by using a fluid exchange machine like the one made by BG. It is a method of choice of many independent service facilities and dealerships too:
The tank inside the machine gets filled with about 14 quarts of oil. It is twice the amount the transmission uses – some of the new fluid goes to waste to ensure that all the internals are completely cleaned of the old contaminated fluid:
The fluid exchange machine is connected in line by hooking up to one of the cooler tubes:
Once the engine is started, the transmission pump will begin flowing oil through the line and the oil will be gradually replaced. The sight tube gives a good view of the fluid's condition:
By the time all of the new fluid has been used, the sight tube should show clean red colored oil. The flush on my xB took about 30 minutes.
That is what is inside the transmission now and all of the old oil has been collected inside the machine:
Since there were no signs of leaks at the transmission oil pan it was decided not to remove it. So the transmission oil strainer/filter was not replaced. While it is recommended to replace it with every service, from my experience it is fine to leave it in until the next time. The transmission filter has much longer life than that of an engine oil filter and I do not think there are any debris or sludge to restrict the flow. Most of the time the special cleaning solution is added to the transmission to help with the process and it is recirculated for the extra 10 minutes or so before doing the fluid exchange.
I chose to stay with Toyota Type T–IV ATF recommended for the car. There are more choices for quality transmission oils available, like RedLine, BG, etc. But it is critical to the transmission's life to use what has been specifically approved for use.
Obviously the flush is not a DIY type of maintenance and is only done at the shop. I hope this write–up will help the fellow xB drivers to understand this necessary service better. Doing it at every 70–80K miles is normal.
Most shops have this type of equipment on hand but not everybody stocks the factory recommended oil, opting instead to use universal fluid which is totally fine as long as its comparability with the transmission is not in doubt.
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20 comments on "Automatic Transmission flush service explained"
April 8, 2012 at 12:35 am
Awesome stuff, Victor!
---------- Post added 04-08-2012 at 12:35 AM ----------
Rep point to you.
April 8, 2012 at 4:14 am
Good points on all items Victor !! Spend a few dollars now and save on problems down the road !!
April 8, 2012 at 4:41 pm
Yeah i hope i get another trouble free 80K out of the trans, but i may do it earlier next time. The xB maintenance book doesn't specify when the fluid has to be replaced, just calls for inspection every 30K. So i think with normal driving (like 50% city/highway) it should be done every 60K ideally. But who has time
April 10, 2012 at 10:06 am
Victor,
What is your take on replacing the ATF with Amsoil ATF?
http://www.amsoil.com/storefront/atf.aspx
Was this done at your shop?
April 10, 2012 at 10:28 am
I don't know about Amsoil- they have really weird way of distributing their product and it's on the expensive side (that's why it's not widely used in the industry- i only see it when customers bring their own oil).
Toyota fluid from the dealer was actually same price as the very good BG Synthetic ATF that we use nonstop, i just wanted to stick to the original oil for my car.
June 6, 2012 at 2:12 pm
Here has been my experience with transmission flushes in general. I have noticed that slipping problems have occurred in most transmissions after severe high mileage has occurred, although this experience has only been with american cars the evidence still supports it. I believe while flushing out all the fluids you are remove clutch residue that the transmissions are relying on to shift smoothly.. JMO
June 6, 2012 at 2:46 pm
So the friction lining residue is suspended in the fluid and is being recirculated inside the transmission past the filter? And removing it leads to improper shifting?
June 6, 2012 at 3:07 pm
So the friction lining residue is suspended in the fluid and is being recirculated inside the transmission past the filter? And removing it leads to improper shifting?
I worked as a mechanic for GM for 7 years although, I never did heavy line or transmission work but for lack of a better term, I feel with transmissions over high mileage going in for flushes have been more detrimental than improvement. I dont think you will have an issue with your being that you did it at 80k in fact I dont even think you will need to be concerned with that thing making it another 80k. its a toyota.. stay on top of your reg scheduled maintenance and that thing will hit 300k easy.
This was just a trend on american cars.. I have a 92 ford ranger that I recently flushed the entire trans and 6 months later I am noticing its slipping out of overdrive. Did the same with a 93 caprice wagon.. flushed it.. 1 year later it went. tossed it around with a few of the tranny guys and was simply explained that the new ATF fluid being completely replaced is too abrasive for the older normal wear clutch plates and have been known to eat them up quicker..
Also manufacturers like Ford, GM, Nissan, Chrysler, Honda, etc., do not recommend a transmission flush for their vehicles. Some may argue "Of course they don't, they want you buying transmissions" ironically enough, I worked at several GM dealerships and all had trans flush machines
June 6, 2012 at 4:44 pm
If you are saying that changing the fluid basically hurts the performance of the transmission and shortens its life then i have to say that i disagree.
One thing i wanted to add to this thread is some info about Toyota T-IV ATF used on Gen1 xB's: It is a Mobil product and available as Mobil 3309.
http://www.mobiloil.com/USA-English/..._ATF_3309.aspx
http://www.mobil.com/USA-English/Lub..._ATF_3309.aspx
July 5, 2012 at 8:28 pm
So what happens if I have yet to do a trans flush and I am at 150k? Should I just do a drain and fill or a full service?