Has anyone gone thru the process where the trans fluid is flushed and changed by the machine that's hooked-up to the trans fluid cooling lines? A friend of mine has a shop with one of these machines and says that it takes about 10 qts of trans fluid to accomplish the flush. BTW he even said that it is a must to use the Toyota WS fluid. Also, I found out that there are many shops that SAY they have such a machine but actually don't. So, anybody tried this method? TKS, John N.
The Prius transaxle is a sealed unit and does not use the flush process. It is a drain and fill process. Your friend is correct that you need to use the Toyota ATF-WS fluid due to the electric motors inside the transaxle. Anyone that tells you that you need to use a flush machine does not understand the Prius transaxle and you need to avoid. This may be true for other Toyota vehicles like the Tacoma. The Prius is a totally different transaxle.
In a normal automatic a lot of the fluid stays in the torque converter when you drain the fluid, usually about 1/3 of it. Your friends machine is designed to replace most of this fluid. The Prius does not have a torque converter, it also has no clutches or gears that shift. When you remove the drain plug from the Prius transaxle almost all of the fluid will drain out so there is no need to flush, just put in new fluid. Tell your friend not to try to use his machine on any HSD equipped vehicles, I doubt he would be able to find a place to connect it to the transaxle anyway.
If this old guy can do it so can you The drain and fill for the transaxle is as easy as changing the oil. Try a search on here for transaxle fluid change and there are many good descriptions with good pictures.
YUP, I got all the info and now will go out and get the 10mm wrench/socket... and some tubing. HOWEVER, I think I'll wait until I get to 50,000 miles to do it...Unless I have a day with absolutely nothing else to do and the weather is beautiful....
Getting a cheap ($2.50) hand pump from Home Depot meant for refilling kerosene heaters means you stay under the vehicle for the new fluid fill. The siphon tube needs to be cut shorter to fit into the transmission fluid bottle, otherwise it works quite well.
The advice I read is to unbolt (loosen) the fill plug before the drain plug, because if you drain all the fluid out and then realize the fill plug is stuck... then you're in trouble. For what it's worth, I also got confirmation that no flush is necessary, it's just a drain and fill procedure.
