ATF Changes ARE required.

The need for oil changes has been documented before but it's good that you bring it up again because it's important. Thanks.

The disconnect between the particle count and ppm that puzzled you is because for the most part the ppm test doesn't break down particles that are big enough to be counted. When you changed the oil, you didn't flush all the particles out of the transmission, nooks and crannies and the film of oil that remained in the transmission retained particles. The large amount of clean oil you put in the transmission compared to the small amount remaining on surfaces in the transmission did a major dilution of the ppm.

A good example of how that works is that an engine or transmission that just blew up can leave a lot of measurable particles in the oil (high particle count) but still have low ppm counts.

A common refrain we get here is that the Toyota Engineers know best, they pretty much do, unfortunately we don't know what they would recommend because the final service requirements aren't set by engineers.

​

 

Aye, many posts on the subject but not in an easy to find location. All the Prius-gurus recommend changing the transaxle fluid at around 30k-60k. I plan to have it done in my 2012 after Christmas when I hit 35k. It's cheap insurance.

 

Deleted duplicate

 

Maybe picture posting is disabled 'till you get more posts? Please do post a pic when you can. I've stuck a small, powerful magnet on the head of my transaxle drain bolt, which magnetizes the whole bolt modestly. But it's not ideal.

BTW, I changed transaxle fluid very early, at first anniversary, with around 15000 km's. I plan to do it every second year, from here on.

<See there's some confusion, this thread is also in 3rd gen prius forum, with pic>

 

The threads can be merged. Report it and request a merge.

 

How is it working? Sounds like a great idea if it works.

 

I got a 4 pack of small/round batteries (described as having 8 lb pull), and put one each on the transaxle fill, transaxle drain, and oil pan drain bolt heads. Time will tell how effective they will be. I'm sure a magnet at the business end of the bolt is better.

I think the setup is fairly effective: when I put a magnet on the head of a spare bolt, I was able to pick up a swiss army knife with the tip of the bolt.

Something of note: you have to take the magnet off the transaxle bolts to put on the 10mm socket when loosening. You could then replace it and spin the bolt off with your fingers. Hopefully there'd be some residual magnetism, and/or the stuff would just stay adhered for that moment.

I do know from experience with Honda transmissions that did come with magnetic drain bolts: the stuff on the magnet is a silvery grey paste, really clingy.

With the magnet on the oil pan bolt I checked: I can place a 14mm socket on without having to remove the magnet. It's best to leave the socket on when unscrewing the bolt. In my experience, if I took the socket off the magnet came with it.

<It seems to be impossible for me to touchtype "magnet". I mis-typed it as "magent" pretty much every time, LOL.>

 

It's such an easy maintenance item there's no reason not to make the change at whatever mile point you wish. I did our '99 at 30k, and will do my C at that pointas well.

This has been fully covered, but not in the C maintenance section.

 

I would like to point out for the non-DIY'ers that this is an easy procedure so do not let the dealer's overcharge you for the job. MANY dealers confuse this service with the service required on the newer Tacoma trucks which require a thermal cycle and flush. That service is $280-$300! 5 dealerships quoted me that price even after I told them the Prius is different and only requires a drain and fill with World Standard fluid. I finally found a dealer that knows the Prius and agreed with me. It cost $90 to have them do it. It was 1/2hr labor charge and the rest was fluid.

 

I've done a little work in this area including our 2010 Prius. My current thinking is:

• 5k odometer (OD) - early transaxle and engine oil change to remove any left over manufacturing debris before it gets much circulation
• 20k OD transmission change - removes last residual material and early wear material
• 50k OD transmission change - final before going to long-term maintenance
• 150k OD transmission change - and every 100k thereafter

The early changes flush out material that can continue to circulate. But after a while, the car reaches a steady state and longer change intervals makes more sense. There just won't that much wear material to removed because the early debris had already been removed.

Bob Wilson

 

Was that Magnuson in Auburn?

 

Yeah. Everywhere else quoted me $280-$300.