This will be for a 2003 Prius. I am curious if it is safe to use Valvoline MaxLife Synthetic if I do a transmission fluid change instead of Toyota ATF WS? It is like half the cost and is suppose to follow all the same specifications. Wondering if anyone has used anything other than Toyota ATF WS for transmission fluid?
No, I've only used Toyota coolants and tranny fluid in all of our vehicles since they only get changed at 5-years or 50,000 miles. Twice as expensive? Check on Amazon, I've seen some pretty good discounts from Toyota part sellers on there.
This is what the 2003 Owner's Manual recommends (page 243): ^ Note, that is not Toyota ATF WS fluid. This is a first gen, the sedan? I don't have a Repair Manual for that. Maybe take out a short term Toyota Tech Info subscription. Transaxle related infot may or may not include a fluid change instruction, since Toyota tends to call the fluid "lifetime". It should at least have a fluid check instruction, maybe enough info for a fluid change as well.
The MaxLife is a universal ATF with a bunch of different friction modifiers to accommodate multiple vendors automatic transmissions. The Prius transmission is basically an electronic controlled CVT with two electric motors built-in; using the ATF to cool those motors. and lubricate the gears. No friction/clutch packs to speak of. Then there's the electronic neutrality of the ATF and how it would play with the electric motors. You can use that stuff and it may not cause enough damage to be noticeable; but if you plan on keeping the car - I'd stick with OEM ATF. It would be too expensive to replace; for the pennies you are saving now. Penny wise but pound foolish. IMHO....
Regarding the fluid specd in owners manual: I would also check with a dealership service department, just in case they know of an updated spec. Hopefully they’re knowledgeable about it.
Here's a real world example of using the wrong fluid in a Toyota. For differentials, there's GL4 and GL5. If you were to put GL5 into a differential (or manual case) that calls for GL4 only, the GL5 would eat up the bronze synchronizer rings in there, ruining it in a short amount of time.)
There are videos online that show how to do it He used ATF WS. Toyota T-IV is cheaper though and if the recommended, will go with that.
Automatic transmission shops recommend 50K-80K mile ATF changes for normal driving cars. Large trucks that tow, should be done every 25K-30K miles. These change intervals are based on ATF breakdown, due to heat and contamination from wear materials flaking off. I've seen worse; but there is a lot of wear material on that magnet. If your going to follow this video; I'd recommend you change that screen filter and see if you can get a paper gasket rather than a cork pan gasket. Cork gaskets tends to shrink and squeeze out, when over torqued. Should be re torqued after a few hundred miles to avoid seepage and leaks. Don't use a screw driver to pry off the pan. Use a putty knife, so you don't mar the soft aluminum sealing surface. Good Luck...
Odds are that it has never been done. I think I used something plastic the last time I removed a transmission pan. I can likely use the trim tools for the job if nothing else. They are plastic. Being that it does not look like that tough a job, good luck in a little ominous however. I would never say that to someone doing an oil change, for example. I have almost never followed a video exactly to the letter. It does give decent guidelines however.
