Transmission fluid

Hello every one.

I have 05 Toyota Sienna, which has around 115k on it. I have couple of questions about the Transmission fluid change.


I like to know that do I have to chance just the pan oil or the complete flush is required.
The Toyota dealer told me that they don’t change the filter, they just clean it. So is it work just by cleaning?
The other mechanic how work at home told me that these dealer flush the oil by using some flushing machine and he told me that I don’t recommend these machines as it create problems. But he also added that he could flush the oil by removing some lines or something. So my question are,

Is he correct about these machines?
And can the transmission fluid could be flush completely by removing the some line or something?


I’ll will highly appreciated if someone can assist me at early as possible as I have to travel over the weekend I prefer to do it before I leave.

Thanks,

Also like to add one more things.
What is fluid detergent and is it recomended?

Thanks

I like to know that do I have to chance just the pan oil or the complete flush is required.

You can do either process. If you just drain the pan, you will not change a good portion of the fluid which remains in the valve body and the torque converter. Therefore, you will have to do it more often.

The Toyota dealer told me that they don’t change the filter, they just clean it. So is it work just by cleaning?

The filter in your transmission is just a screen which prevents large particles from getting into the valve body and freezing up valves, rendering your transmission unable to shift. It is normal to not change that filter.


The other mechanic how work at home told me that these dealer flush the oil by using some flushing machine and he told me that I don’t recommend these machines as it create problems. But he also added that he could flush the oil by removing some lines or something. So my question are,

Is he correct about these machines?

Not really. I have not seen them cause a problem. In general, they are very much the same process as he would follow. In both cases, you have to pump fluid out of the transmission and replace what is pumped out. The machine the dealer and many other places use, uses the transmission oil pump (while the engine is idling) to pump the transmission fluid out of the transmission and into the machine. The fluid pumped out of the transmission pushes on a piston which then pushes fresh fluid out the other end of the machine and into your transmission to replace what was pumped out. Your mechanic would undoubtedly do something similar. He would use the same lines (to your radiator) to change the fluid as the machine does.

I think what your mechanic is being unclear about is his reference to the potential problem with flushing the transmission vs draining the pan and replacing only a portion at a time. If your car has many miles on it and has never had the transmission fluid changed, it may cause a problem if you flush it and replace all the fluid with new. Your fluid would have to be really bad with the seals being very bad to have a fluid flush cause a problem in this way. I think he is just trying to steer you away from having the dealer do it so that he can and make money off of your business. I think he is proposing doing something identical to what the dealer would do. Probably charge you less, though.

When I change my fluid, I first drain the pan, refill the transmission pan with new fluid, and then idle the engine to let the transmission pump out one quart at a time, and then replace a quart manually. It is more trouble than just allowing the machine to replace the fluid as pumped out, but the results are the same.

And can the transmission fluid could be flush completely by removing the some line or something?

Not exactly. First, you have to drain and refill the pan with fresh fluid, then use the transmission oil pump to drain the remaining fluid in the torque converter and valve body. This happens through the cooler lines to your radiator. Your radiator has a transmission cooler inside it.

Also like to add one more things.
What is fluid detergent and is it recomended?

Thanks

Don't add anything to the transmission fluid. It already contains adequate detergent. The detergent additive just suspends small contaminants. All brands of transmission fluid contain detergent.

If your car has many miles on it and has never had the transmission fluid changed, it may cause a problem if you flush it and replace all the fluid with new. Your fluid would have to be really bad with the seals being very bad to have a fluid flush cause a problem in this way.

Thanks, But I'm little confuse about your above quote. You mean to say that if I change the complete fluid, it can creat problems.

My van has 115k and since I bought (80K) I never change the fluid but when I went to the dealer they recomend to do the complete flush as the flued is dark. By the way what is the color of new fluid. When I checked mine its kind of redish brown or very dark red.

Thanks, But I'm little confuse about your above quote. You mean to say that if I change the complete fluid, it can creat problems.

My van has 115k and since I bought (80K) I never change the fluid but when I went to the dealer they recomend to do the complete flush as the flued is dark. By the way what is the color of new fluid. When I checked mine its kind of redish brown or very dark red.

Flush it. Your fluid is a normal color for used fluid.

Flush it. Your fluid is a normal color for used fluid.

Guys, I respect all your suggestion but mean while I also mailed to Toyota about the transmission flush, please don’t take it personal and their reply is: We don’t recommend Transmission Flush.
Now I’m confuse.

Transmission flush is a term that is often mis-used.
Most places that do a transmission fluid "flush" are only exchanging the old fluid for new.
The process that your friend mentioned about removing lines and changing the fluid is the home way to do it.....and is what I do.

The fluid "flush" machine that your dealership uses.....is really a fluid exchange machine.
They connect the lines for this machine to your vehicle's transmission cooler lines.
Then they start your vehicle's engine and let it run at idle.
The pump IN YOUR TRANSMISSION pushes the old fluid out through 1 of the cooler lines and it also now flows through the dealership's machine.
The machine measures how much fluid is coming out and simply lets NEW fluid go back into your transmission at the same rate that the old fluid is coming out.

So, the dealership machine is simply replacing your old transmission fluid with new fluid.
You do not want ANYTHING but new fluid to go in.......no cleaners or chemicals....as they are not recommended by TOYOTA.

If you do not want to use the Dealership service, you can remove the drain plug from the bottom of the transmission......draining the fluid in the pan.
Put the drain plug back into the transmission.
Then....measure what came out.....and pour that same amount of NEW transmission fluid through the transmission dipstick tube.
However, make SURE that you get the correct fluid for your vehicle.
I think that the 2005 Sienna calls for a fluid that meets the T-IV specification.
So, make sure that the fluid you use lists that on the label.
Draining the transmission pan at the drain plug gets up to 1/2 of the total amount of fluid.......so you will get 3 to 4 quarts of the 8 quarts that are in there.
The rest of the fluid is in the torque converter and elsewhere in the transmission and cooler.
I would drain, fill........start the motor and let it idle a bit....and then drain and fill again.
This will get most of the fluid replaced....