transmission oil change
 

Hi ,
I've read here on this forum that the transm oil can't be change 100% but only 4gal out of 9gal if you remove the oil pan.......and I was wondering why noy using the radiator(for cooling transm oil)pipes to flush out the whole 9 gal of the transm oil ? did anyone do that way....it's possible?

It isn't gallons, it is litres or quarts.

If you use the cooler lines to drain it, you will have to be running the engine and have the transmission in gear to get everything out. You don't just need to get the fluid out of the cooler, you need to get the fluid out of the torque converter and that is why you would have to be running it. There is a risk of damage due to running the transmission without fluid.

The usual way to use the cooler lines is to connect a flush machine, which often applies pressure. The risk here is that high pressure flushing can dislodge sediment. You can use some flush machines without pressure, removing fluid and adding it at the same time. You need a lot of fluid in this case, but it is possible.

If you want to get more than 50% of the fluid out, the accepted method of doing that is to drain and refil the transmission several times. You get 50% out the first time, then 50% of the mix out the second time (leaving 25% old fluid) and so on.

thank you JCL...!