Hey all, Have a 2011 Prius model 3 at 155,000. Never had my transmission oil changed as I don’t recall the manual ever having a maintenance schedule for it. Not experiencing any issues right now but is this something I need changed? Like to hear recommendations and experiences from people who has had it changed man’s those that haven’t. Also, I’ve heard that servicing transmission oils can be risky as well as putting in new oil can cause leaks and issues due to having removed broken down matters that “plugged in” areas where necessary; also I heard it might apply up out transmission as it’s CVT? Thanks!
There is no harm in changing it at 155k miles. 4 quarts of Toyota WS fluid. Also these transmissions are plentiful due to their low failure rates, changing the fluid or not is up to you. But I personally don't believe in "lifetime" fluids
I’d do it. If you’re planning to DIY, it takes about an hour, and the Toyota ATF WS plus two washers should be around $40 USD, through dealership. More info in one of my signature links. (On a phone turn it landscape to see signatures)
Get yourself a big fluid syringe thing, it makes life really easy. I changed mine at 98k using an electric pump which worked, but was a bit clunky. Then I had to top it off after changing an axle and used one of these syringe things, and really this was so much simpler I think this might be my new favorite instead of the electric pump: Link to syringe on Amazon
The transmission is cvt and not like the torque converter transmissions so it will be fine if it’s the first change.
We've been using malife Low Viscosity mercon 6, 1 gal jugs from Walmart (red bottle)for years and reusing the crush washers for a decade without incident. Service more than a hundred so far without problem
"Lifetime" for car manufacturers mean until the emissions warranty expires. There is no sense in using anything other than the proper transmission fluid from Toyota. The cost of aftermarket fluid is only a few dollars, and it may or may not be compatible. You also risk mixing fluids with adverse results because the oils may not be compatible. WHY risk it just to spend $5 less????
Yep go ahead and drain and fill. Buy a couple of crush washers for the drain/fill bolts. Like Mendel, I also refilled ours via a funnel with about a 3-foot hose on the bottom....just place in the rear of the engine bay, near the brake fluid canister, and snake down the hose. I had my wife act as my spotter as I refilled...told me when it was overflowing. (Our 2017 Prius took 3.75 quarts of Toyota WS fluid.) Oh, if this is the first time it's been done, expect those bolts to be TIGHT! I'd tap them a few times with a hammer before attempting to break them free and make sure you have a long handle on the wrench.
Use a 1/2 inch breaker bar with a 10mm hex socket. MAKE sure the socket is 'seated' properly - you don't want to round-off that hex bolt. Always break lose the fill port FIRST! If you can't get that one loose, no point in draining the transmission, if you can't refill it. re: pouring. a one man job is fine. Put in 3 quarts then go slow on the last half to three-quarters quart. You should hear it dripping into a clean drain pan. Good Luck.
