Cvt & Rear Differential Fluid

[lenore]

Ok guys, got my new to me 2008 RX400h and because of the unknown fluid conditon in the CVT and rear differential would like to change fluid. I have read the post, and saw they they take WS fluid...here are two pictures with plugs circle in red. 1. Are these the drain and fill plugs, 2. WS is correct? CVT 4qts Rear differential 2 qts?

[lemon]

Yes for the locations. Just a tip, make sure you loosen the fill plugs first, so you know you'll be able to refill. Wouldn't want to drain, then find the fill plugs too tight to refill. ATF-WS is the right fluid. I can't remember the capacities from when I did mine (and I'm not at home to check my service manual, but that sounds right (capacities might be listed in the owner's manual, maybe?)

The service manual procedure includes the step of running the ATF electric pump for a short time after replacing the fluid. I just filled mine to the bottom of the fill hole, drove it for a very short distance (it's supposed to be checked not too hot, not too cold IIRC) then pulled the plug and double checked the level. Can't remember if I had to top up or not.

When I get home I can post the actual procedure per the service manual.

There is another drain plug on the bottom of the CVT - this drains the coolant (for the inverter and electric motors) - be sure not to remove this one - unless you're planning on changing the inverter coolant, which also has a replacement schedule.

[lenore]

Thanks Lemon, with 88k miles and the carfax report doesnt exactly tell you what fluids are changed...I felt this would be a good start from a maintenance position....Yea I know timing belt coming up...

[lenore]

By the way these are good pictures for anyone wanting to know....

[lemon]

Coolant (engine and inverter) need changing at some point. You might hold off on the engine coolant, as it will have to drained if you need a new water pump when you do the timing belt.

Brake fluid should be changed every two years, regardless of mileage - you can't do this yourself as you need to be able to cycle the pump that makes brake pressure (since we don't have brake booster like on a non hybrid, you can't simply pump the brakes to get fluid out at the wheel bleeder bolt).

Air filter and cabin filter?

[lenore]

whoa got a lot to learn, so you cant pump the fluid out with the brake pedal...interesting....

[lemon]

Not as far as I know. I read of someone who did a bleed using traditional method and got warning lights on dash and squishy pedal. Makes sense, since the brake pedal is not mechanically connected to a booster a la a conventional non hybrid vehicle, since braking is sometimes needed when the engine is off, so there would be no vacuum assist.

Now, I 'suppose' you might be able to bleed if you left the vehicle in the 'on' position and pumped the brakes, as this would conceivably run the pump that creates pressure for the braking system. However, this is not the procedure laid out in the service manual. The manual instructs one to cycle the pump using the Lexus computer (the handheld one that plugs into the OBDii port) to properly bleed the system (it's still bled via the individual wheel bleed bolts, but the pump must be run to push the fluid out).

[lenore]

OK, did the fluid changes, Looks like the original fluid judging by these pictures...little over 4 qts for the front transmission and 2 qts for the rear. Used WS toyota fluid, was $8 per qt. in the pictures see the sample of new and old on the paper. This was at 89k miles...note the sample was from front. The rear still had a red color.....

[clickart]

Can somebody write the procedure to change the transmission fluid on the rx. I was looking for the dip stick today for the transmission but can't find any. Where do you refill the new transmission fluid?

[lenore]

iF YOU LOOK AT THE BEGINNING OF THIS THREAD THE PLUG IN THE UPPER LEFT CIRCLED IN RED IS THE FILL PLUG FOR BOTH TRANSMISSIONS. THE LOWER RIGHT PLUG AS CIRCLED IS THE DRAIN PLUG....THERE IS NO DIPSTICK, YOU FILL UNTIL IT POURS OUT. THAT IS THE PROPER LEVEL...CAN BE .5MMM BELOW THAT HOLE OR EVEN WITH THE BOTTOM OF THE HOLE.

[clickart]

What about the refill and drain plug for the rear differential fluid? Is it located somewhere near the rear transmission refill and drain plug?

[lenore]

The second picture in this posting is the rear differential and shows the fill and drain plug...

[kueagle]

Not as far as I know. I read of someone who did a bleed using traditional method and got warning lights on dash and squishy pedal. Makes sense, since the brake pedal is not mechanically connected to a booster a la a conventional non hybrid vehicle, since braking is sometimes needed when the engine is off, so there would be no vacuum assist.

Now, I 'suppose' you might be able to bleed if you left the vehicle in the 'on' position and pumped the brakes, as this would conceivably run the pump that creates pressure for the braking system. However, this is not the procedure laid out in the service manual. The manual instructs one to cycle the pump using the Lexus computer (the handheld one that plugs into the OBDii port) to properly bleed the system (it's still bled via the individual wheel bleed bolts, but the pump must be run to push the fluid out).

Hi Lemon,

Regarding your statement on changing the brake fluid, I have a pump that I have used on my non-hybrid vehicles (Civic, highlander, and Ford). With this pump, I can put the brake fluid in and pump fluid through the break master cylinder. Then, I open the bleed nuts (one at the time) until I see the clear fluid coming out. I am wondering if I can use this on the RX 350 hybrid.

Thanks,

John

[fery]

The transmission has an oil cooler. It is installed on the left inside of the front bumper. Oil circulation carries by electric oil pump located above the the oil cooler.

I'm not sure if you remove the drain you could take all oil out.

Did you get all 4 quarter out from drain?

oil cooler.bmp

front transmission.bmp

[lenore]

I got approximately 4.2 qts. Drove it for a week, and did it again...The fluid is pristine now....

[mynewhybrid]

Totally agree with the necessity of fresh transmission fluid and it sound like a relatively easy task. I have 2 questions: 1. I service my RX400h on 8" ramps. As I looked at the fill plug it appeared that the elevation of the front wheels might result in a slightly lower fill. Need I be concerned about this? 2. I read about the propensity of WS fluid to be contaminated by moisture. Any precautions to take here? Thanks in advance for your responses.

[lenore]

I would not fill on the ramps, the car has to be level... as for the moisture thing, why would that be a problem when changing it....?

[cduluk]

Jeesh, i should really have my Rx400h's transmission fluid changed. If that's how brown your fluid was, i can only imagine how bad mine is considering the way i drive...

[YotaLVR]

Do I need to have this done by the dealer at 90k miles?

[lenore]

I would, 90k is the max I would go without the fluid change...just me. I owned an RX300 with failed transmission, preventative at least makes you feel better....

[lemon]

I change mine every 48000 KILOMETRES. The fluid is cheap and the process is relatively easy. Fluid transfer pump required.

[lenore]

Well here is tranny fluid changed at 18k miles with total vehicle mileage at 129k....Dirty on left....By the way the fluid is up to $11 and change per qt. But if you live in my neck of woods (Sacramento) you can get 20% discount on all parts on sundays at Roseville Toyota....

[Kaz28]

I changed the rear transmission fluid at 60k KM.

Used the original Toyota ATF WS oil as per Lexus owner's manual.

Since that I experience a strange short scroop sound coming from rear irregularly - only at the moment I press the gas pedal to accelerate the car, but not every time.

The level of fluid was checked OK few times after the change, there was no need to refill.

Any clue what could be the reason ?

[lenore]

No clue, Maybe a coincidence and something else is making the noise.

[raldin]

I have a 2007 Highlander Hybrid with 96,000 miles and just changed out my transmission and read differential fluid (I doubt it had ever been done before). A couple of notes from my experience:

I bought the car used, but my sales sheet said the vehicle had the tow package. The dealership told me that the trans would take 4.2 quarts with no tow package and 4.4 quarts with the tow package. When I drained it, I actually had about 4 quarts come out and that is about how much I put back in. Also, when I opened the fill plug, fluid did start coming out. So it was filled some amount higher than what I could put back into it (I did have it on a level surface). The transmission fluid was a light brown color and no longer red. Unfortunately there is no magnet on the drain plug. I plan to re-check in a couple of days to make sure the level is still good.

When I drained the rear differential the fluid practically looked like it was new. The plug is magnetic and it did have some very fine black material on it that I wiped off. The fluid looked so good, I don't think I will be doing this again for a very long time. One thing to note is that the rear differential hex plug did not take the 10mm hex socket, it was slightly smaller. I believe I ended up using a 3/8 hex socket instead and that fit pretty snuggly