Both of my vehicles (1999 Ram and 2013 Subaru) have transmission dipsticks. Both of my wife's vehicles (2006 Jaguar and 2015 Lexus) do not. You can guess which two vehicles I prefer....

 

A few years ago a guy on eBay developed and sold a slightly longer metal overflow tube to replace the red inner overflow tube. The claim was that it allowed one to conduct the transmission fluid overflow test at normal operating temperature instead of the narrow window specified by Lexus. I got one, but have not seen them on eBay for a few years.
The instructions advise to install it, then before adding fluid to run the shifter through the gears to make sure it does not hit the longer tube. It fit just fine in my RX. It also included a hose with a banjo bolt to fit on the fill hole. You install it so the fill is at the engine top near the battery. At the top is a small PVC pipe thing with a removable top to make it easy to add more fluid anytime. So on future drain and fills you do not have to remove the tire etc to add fluid.
I did the usual drain and fill, overfilling by a measured amount. Drove around for 20 minutes, returned and let it idle in place for 10 minutes before removing the drain bolt. I measured what overflowed out and it was correct.
This was a great innovation for about $50 and I wish I could locate it again.

 

^^ Interesting, and very innovative.

 

Agreed. I prefer the level straw method of fluid filling/checking over the dip stick method. The process is very easy with just a few tools(long tube funnel, proper sockets, and jack stands).

My 2007 Highlander has the old 5-speed automatic with a dipstick, but it is darn near impossible to get a good read on the transmission fluid dip stick while the engine is running due to fluid smearing all over the dip stick since the dip stick tube is also where you add the fluid.

 

I think the longer tube may be used by Toyota/Lexus techs to check the transmission fluid when hot for diagnostic purposes. I sort of recall reading something about that procedure.
Maybe a question for the Car Care Nut.

 

Hello to all. I ask for advice. I drained the ATF fluid on my 2010 RX with 160,000 km on it. Before that, I drove 10 km and the car was on the street for 0 c 20 mins. the oil was warm to the finger for about 45 Celsius it looked brownish but not tragic. drain showed 1.6 liters. (on the RX 2010 180 00 km my wife had 1.8l.) I filled 2 bottles, started the car, played with the selector for a couple of minutes and 0.5 liter can came out. That is, it turned out about the same. Both cars shift well before and after without problems. Do I need to measure temperature for good level or just continue draining and filling with the same amount of oil? I don’t think that 1.5 liters of fresh oil at a colder (room )temperature will expand to critical . Thanks'

 

The proper method to set transmission fluid level is to let the transmission fluid drain out the drain hole with the red level straw installed in the transmission pan when the fluid reach a specific temperature until the fluid only dribble out of the drain hole. However, if the transmission is running properly before the drain then you can just drain the pan with the red level straw removed and then just replace the fluid amount that drained out if you perform the service quickly.

I say this because fluid will continue to drip out of the transmission pan from the valve body/pump while the drain plug is open and the level straw removed, which could make your initial measurement incorrect when it comes time to top off; especially if you leave the drain plug open for hours or over night.

 

2010 RX350 120K miles
Should transmission fluid be drained/filled at 120k miles? I am a new RX 350 owner and don’t really have the full service history. I know that service was offered to previous owner at around 110k, but refused. Local Lexus/Toyota asking $380 for the job and say that because it’s a sealed system, they can’t really tell until they do the drain/fill. If the previous owner has waited this long (which I don’t really know), will drain/fill cause more harm than benefit? Tranny seems to be working OK at the moment.

 

I have a simple rule; when in doubt change it out.

However, there is always a risk when changing old transmission fluid in a older neglected transmission. Sometimes the old clutch filled transmission fluid is the only thing keeping the transmission from slipping.

 

Hello i have a question about the operation of the transmission. How can 1.6 liters ( 1 drain) of fresh oil affect the operation of the transmission? Better oil, better pressure.etc Can discs wear out like a brake pad when they wear out? grinding in and still work . Why, if you drain the atf from the pan, for example, once to make sure that everything is ok , it could be a problem. It turns out that the emulsion in the oil is so strong and without it there will be no clutch. then it turns out that the oil has drained overnight in pan and NO emulsion on disk ? then in the morning trans won’t go until oil stirs it? Of course, the new oil washes away the deposits, but it also works better. And if the atf is very old how to check and at the same time slightly refresh the liquid. at least once

 

I assume that you are asking about how the old ATF with old clutch material(grit) can keep the transmission from slipping. The grit is suspended in the old ATF and it provides grip for the worn clutches to bind to. The problems when using fresh ATF fluid is that the grit is also removed with the old fluid and without the grit the old clutches are not engaging properly due to being worn down; which causes the transmission to slip when changing gears.

You can use fresh ATF fluid with a transmission anti-slip additive to help prevent that problem on older transmissions.

 

If this was true wouldn't there be additives that contain the same materials that can fix a slipping transmission?

 

I understand that the emulsion is dissolved in oil and does not precipitate. The bigger question is when the discs close together or float in the air when worn out. Is there a chance of grinding and polishing them together? If you do not touch the ATF, the solenoid may be blocked by dirt. There are many reasons and when we thinking about the clutch of discs we forget about them. My opinion is as written above. cold drain and fill. At least once to make sure how much and what kind of liquid. And if there are any concerns, return the old fluid back. I had a ford escape. . from 2 to 3 there was a delay with a characteristic freeze and zzzz 200 000 km of mileage. ATF did not change. 5 liters drained in the garage and a new one was poured in. My nephew has had the car for over a year and I yesterday drove it. Works great, clear switching. This is of course an example, but it’s something to think about.

 

The transmission holds about 7 quarts. By doing a cold drain and fill you only replace about 1.8 to 2.25 quarts depending. This is enough to refresh the additives and reduce the debris level in the fluid, but not enough to interfere with operation of the clutches etc on an aging worn transmission. It is a reasonably safe procedure on a higher mileage transmission.

I did it on my old 2013 Sienna when bought with 89,000 miles and apparently the original fluid and it shifted better afterward. I then did 2 more cold changes and it still worked great at 120,000 when traded in.

FYI there are various transmission anti-slip additives by companies such as Lubegard.

 

Hey clutchless- on an earlier post in this thread, you said something about "overfilling alittle by a 'measured amount'? What did that mean, and/or how much "extra" did you add? I ask because I have just started the procedure of 3-4 cold drain/fills. After 62K miles, it was REAL dark on the first drain yesterday...Thnx for any info.