Jabberwock

Just got done with my second of three AT drain and fills on my 2006 LS430. Car has 77,600 miles on it. Plan on doing the third one later this week since I am moving and need to use up the last of the ATF rather than moving it. So far with the car's front tires up on ramps/stands each time just slightly more than 2.5 quarts have drained out. Fluid was very dark brown on the first drain but was not burnt or burnt smelling at all. Second drain fluid was significantly lighter but still darkish brown.

Once I had the front of the car up high enough, I had no issues removing the 2 bolts with a 1mm ratcheting box wrench on plastic side cover or loosening the subsequently revealed side fill port bolt - used a 24mm box wrench on that. The ATF pan drain bolt was also super easy to remove. Draining ATF takes just a few minutes. I drained the ATF into an empty oil drain pan and then measure exactly how much ATF drained (by pouring into a graduated/marked in half quart increments 1 gal plastic jug) so I could pump back in exactly the same amount. Also made sure I did the drain and fill when the car and ATF fluid was cold so there was no measurement error related to fluid thermal expansion.

Pumping the new fluid in from the one quart ATF was a bit of a challenge. In the end I used a 4ft long piece of clear plastic tubing that fit the pump spout and had my wife stand next to the car running the ATF container pump while I was under the car holding the other end of tube in the ATF fill port.

Going forward I will likely do one drain and fill of the ATF every 15k miles. I intend to keep my car for another 100k and want zero issues with the AT so hopefully this will help. Given how easy it is seems worth the effort to me. I am used to doing a yearly 3 quart ATF drain and fill on the wife's Highlander - on that car the job takes 15 minutes.

First drain and fill took maybe 1.5 hr because I was going super slow and careful. Second drain and fill took maybe 40 minutes - still going slow and careful. Third will likely take 30 minutes. Its a really simple easy job. Hardest part is jacking up car for ramps/stands (I use both to be extra safe) and clean up/fluid handling/recycle/etc. Very satisfying job. Absolutely no change in the way the AT in the car feels.

tradosauru

That is not the way you do a drain and fill. I did it wrong by not idling the car while checking the over flow. For all you know the transmission was either under filled or over filled.
I will be doing mine this Tuesday and will document with pictures.
After reading the technical manual on checking the fluid level I am more adamant that most people doing it wrong.

Jabberwock

I understand what you are saying but maybe I was not clear in my description or giving enough background.

1. My situation may be a little unique in that my car has original factory fill ATF in the AT. No signs of any ATF leak, and the AT has never been serviced. And the AT on my car was working perfectly.

2. I precisely measured the ATF that drained out. The drain and fill was performed with the car was stone cold, and with both old and new ATF at same temperature so there could be no measurement error due to temp difference (thermal expansion) in fluids.

3. Because I precisely measured the amount of old ATF that was drained, I replaced new ATF in the exact same amount as I drained. So if I can make the assumption that the original AT factory fill was correct then the amount of ATF in my AT is exactly the same now as before drain and fill.

4. The AT works perfectly after 2 drain and fills using above method.

I am aware of the Lexus detailed instructions for determining correct ATF level. This is absolutely necessary for Lexus techs when servicing AT fluid because they have no idea if the AT in a random car has correct level when it comes in the shop. They also cannot wait for AT to cool down so they service fluid while it is cold or various stages of hot. As a result they must use the documented multistep method for determining correct ATF fluid level at documented temp range per the manual.

airchomper

If it's working well for you, more power to you.

But figuring out the replacement volume of fluid by measuring it (volume or weight) probably isn't as accurate as we would hope. The fluid will pick up wear particles and expand in volume (also, I'm convinced that WS and Type IV 'shear' down to their proper viscosity grade when the pass through the torque converter which seems to change the fluid's volume).

The factory service manual procedure exists for a reason - doing the job correctly every single time.

But I think people worry too much about the fluid levels in these transmissions. I know the off road Toyota community generally doesn't sweat ATF levels. The transmissions seem to be fine +/- a pint in either direction. Some people even think it's okay to be half a quart overfilled.

This is a clever technique and probably much faster than doing it the 'right' way. But at what cost?

Lavrishevo

iTrader: (1)

If you are low on fluid will notice hard downshifts and other issues. They are rather sensitive to being low on fluid. It is better to over vs under on these transmissions. You are correct chomped that the measure method is not technically the correct way but it had worked for many over the years here on CL. At what cost? Apparently very little cost as it saves the end user a lot of money doing it themselves.

tradosauru

If you are going to do it then do it right. It doesn't take that much effort.
I agree that the transmission seem to be a bit more forgiving than we imagine. I know mine was overfilled by a quart.
Also isn't the drain plug toward the front of the car on the transmission pan? If so wouldn't you get more fluid out by draining it while level or at the very least with the back end of the car on ramps?

warminwisc

Thanks Jab, I would think you will be fine you are thorough and pretty sharp.

Lavrishevo

iTrader: (1)

You get about 1.5 more quarts from the torque converter while the front is up on ramps or jacks.

tradosauru

I'll test this theory out tomorrow.

I'm wondering if just by sitting for a few hours if the torque converter just doesn't drain fluid into the pan anyway? Or just jack the front of the car up and leave it for about an hour and then level the car and drain it. If the drain hole is closer to the front of the car I can see fluid still left in the pan if the car remains on ramps.

takimanpgt

Point noted but if you are going to be doing drain and refills, does it matter?

Jabberwock

Completed 3rd ATF drain and fill on my 2006 LS. This time the ATF fluid draining out (from the second drain and fill) was noticeably red and much more clear than the first drain.

Exactly 2.5 quarts drained out and that is what I put back in. This involved some thoughtful fluid juggling to make up for about 2-3 oz extra fluid that was left in the hose when each quart bottle was pumped out.

Having done this job 3 times now it has become easier each time. Once the car is up on ramps I can literally get the cover off, fill port open and ATF drain bolt removed in less than 5 min. I let the ATF drain for 30 minutes just to get as much as possible drain out.

As before AT operates as before with zero issues, no change in AT behavior or feel.

At this point I will likely repeat the ATF drain and fill once a year going forward, I'm confident this will keep my ATF fluid in great shape over the years.

tradosauru

Awesome.
I think the Lexus transmissions are very forgiving as i know mine was over filled by a quart.
And based on how people are doing their drain and fill they are probably over or under filling the fluid level.

ejthomp

Looking forward to pictures and your tutorial!

BMW7_LS430

I completed my second drain/refill this week after last year' first drain/refill. I made some mistakes but in the end I checked fluid levels with infrared heat gun to make sure I have right levels of fluid.

Disclaimer: This is not a Lexus recommended procedure but then Lexus also says it is lifetime fluid therefore I am going to rely on common sense rather than Lexus Marketing.

Here is an additional tip for people who want to drain and then refill with exact quantity through side fill port.
Jack-up front of the car or use ramps. I prefer ramps.
Drain fluid through drain plug.
Put drain plug back on.
Measure drained ATF.
Open side fill port.
Attached a hose to funnel.
Open hood and keep funnel in the engine compartment. Engine must be completely cold for the next step.
Route hose through engine compartment near break reservoir down to side fill port of the transmission.
Pour exact quantity through funnel. Now there won't be any residual fluid in the hose.

I also did oil change and brake bleeding. Now my car drives and shifts perfect!

tradosauru

It will probably be next Friday as I had to leave my car at the audio installation garage at Best Buy.