Transmission fluid change

[fgoodyear]

My dealership says that @ 30K they change the transmission fluid & filter. I cannot find any reference to changing the fluid & filter, only checking it @ 30 K intervals. What is the recommendation for doing this? Need to now before scheduling my 30K service

Thanks,

Frank

[fnc]

Here is how I view lifetime fluid. When installed it's life begins, when the component it lubricates fails, the lifetime of the fluid is over. You get new fluid with the new component.

Now, I would suggest changing it if you can. 30k is not an unreasonable interval to do so. The fluid in the Prius transaxle does get dark over time, (it is nice and red new) conatminents are present in the fluid at this time.

Preventive maintenance is just that, you are trying to maintain your vehicle to prevent a break down or component failuire. Compare it to cooling systems or brake fluid. They wear from the inside out, so a radiator hose may appear to be in good condition, however it could be worn on the inside and about to fail.

HTH

[Patrick Wong]

Hi Frank,

Note that there is no transaxle fluid filter in Prius. The 2G model needs 4 quarts of Toyota ATF WS when doing a drain and replace. No fluid flushing is required.

Several Prius owners have had their used transaxle fluid tested (including me) and found large amounts of aluminum, iron and silicon particles in the used oil. This provides further motivation for periodic replacement of that fluid.
DRAFT Transaxle Oil Testing Results
Transaxle Oil Analysis

I change my transaxle fluid at 30K mile intervals, a relatively simple DIY task.

[edthefox5]

Hi,
I changed my 07 out myself at 5,000 miles as I plan on keeping this car a long time. Its cheap compared to losing the trans at 75K. I up-graded to this:

Red Line Oil: Gear Lubricants


and the car seems to like it. Smooth smooth. I noticed a difference at 70-80 mph's. Although at 10K I plan on doing a UOA on that fluid.

[dogfriend]

Hi Frank,

When they give you the price for changing the ATF, be aware that you can buy the WS fluid for about $5 - 7 per quart (I paid $5.20) and the only other materials needed are two aluminum washers for the drain and fill ports (about $ .80 each). It only takes a few minutes to drain and refill. So if they quote a couple of hundred for the service they are way out of line. It is a fairly simple DIY service.

[fgoodyear]

Thanks, I appreciate all replies on this. My 30K service is supposed to be about $120 more than the 15K for just the tranny fluid change and cabin filter change being extra...... I think I can change my own tranny fluid for that... and check the cabin filter.

[Patrick Wong]

Originally Posted by fgoodyear

... My 30K service is supposed to be about $120 more than the 15K for just the tranny fluid change and cabin filter change being extra...... I think I can change my own tranny fluid for that... and check the cabin filter.

OK, if you plan to change the transaxle fluid yourself, you will need the following tools: 24 mm (or 15/16") socket for the fill plug, 10 mm hex key socket for the drain plug, and a funnel with a three-foot-long flexible tail to make it easy to add fluid through the fill hole.

The cabin filter will cost $15 plus shipping if you buy from one of the Toyota dealers that sell discounted parts over the Internet; may cost $20 or more from your local dealer.

[fgoodyear]

Thanks, I appreciate the info. I have all the tools needed, now where is the filler located?

[Patrick Wong]

Originally Posted by fgoodyear

...now where is the filler located?

Raise up the Prius with four jackstands so that it is level. The fill plug is located on the side of the transaxle that faces forward (towards the radiator). It is not necessary to remove the engine under cover in order to access the fill plug.

When refilling, place the funnel near the radiator and inverter, then snake the flexible tail down to the fill hole. Then you should be able to add the 4 qt of ATF WS without spilling it on your driveway.

[richard schumacher]

This calls for Toyota's ATF, right? Something about avoiding dissolving the insulation in the motor/generator windings?