Possible Rx300 Tranny Problems

[bluestu]

Yeah, you're right, that car sounds messed up, whatever it is.

[bluestu]

The last audio segment sounds the worst and he has the recorder taped to the rear fender above the wheel. It sounds similar to my mountain bike's disk brakes. I would check the brakes and rotors. That's too far from the transmission to be that much louder.

[wwest]

For an AWD the rear PTO is mounted directly to the transaxle diff'l case. The diff'l runs in ATF and the PTO in gear oil. For AWD RXes prior to 04 the PTO also contained a viscous clutch or coupling in which the viscous fluid would be HEATED on adverse roadbed conditions to cause it to couple some level of engine torque to the rear driveline.

It is entirely possible or probable that repetitive heating of the VC fluid results in heating of the ATF and it often becoming burned. Does any one know how HOT this fluid must become to couple 25% of 200HP to the rear drive line??

[thomaskuhn]

I took the car in yesterday to CarMax to have it diagnosed. Today I heard that they turned all four rotors (They say that was the cause of the sound), and flushed all 16 qts. of transmission fluid. From what I understand, the sound is gone. Do I still have reason to be overly concerned about the transmission? My wife now wants a FWD version. I do not know how much of a hassle this will be with Carmax, has the problem did not seem to be the transmission, but the rotors. Why then did they flush the trans. fluid? I called back to ask if they found any metal in the flushing, but have not heard back yet.

Tom

[bluestu]

If the sound is gone, I wouldn't worry about it. You should have the transmission flushed at least every 30k. So they also said the transmission holds 16qts? If this is true, then the drain and fill of 5 qts. is useless, which would explain why so many transmissions are burning up prematurely, especially the ones that are exposed to high temperature environments.

[LexKid630]

If the sound is gone, I wouldn't worry about it. You should have the transmission flushed at least every 30k. So they also said the transmission holds 16qts? If this is true, then the drain and fill of 5 qts. is useless, which would explain why so many transmissions are burning up prematurely, especially the ones that are exposed to high temperature environments.

←

Did you happen to mention to them that you thought it was the transmission making the noise? My guess is that they have NO clue the transmissions are a problem on the AWD rx's, so they read up on it and flushed it to make you think they're responsible...

Glad to hear it's not the transmission after all! If that wasn't the problem you should be fine i guess...check if the fluid was dark and smelled burnt anyway.

I would still go with the 2WD since you'll never need the AWD and it's only an accident that "could" happen in the future.

No one knows for sure if it WILL fail, you can only prepare yourself for the future!

Good luck with your decision!

[wwest]

It takes 16 qts to FLUSH the transaxle, only 5 qts to fill to capacity.

Consider yourself lucky that the coolant system can be flushed with just plain old tap water.

[bluestu]

It takes 16 qts to FLUSH the transaxle, only 5 qts to fill to capacity.

Consider yourself lucky that the coolant system can be flushed with just plain old tap water.

←

I'm sorry, but your information is incorrect. The transaxle capacity is considerably more than 5qts.. Why don't you call around and find out for yourself.

[lenore]

The U140E tranny holds 8.8 quarts and the U140F tranny holds 9.8 quarts for total refill.

[bluestu]

The U140E  tranny holds 8.8 quarts and the U140F tranny holds 9.8 quarts for total refill.

←

Well, ok. That tells us that a lot of fluid is trapped in the torque converter and can't simply be drained from the two plugs underneath. Mixing old, burnt fluid with new fluid is not proper maintenance. It would be comparable to draining half of the engine oil out every time you performed an oil change.

[artbuc]

The U140E  tranny holds 8.8 quarts and the U140F tranny holds 9.8 quarts for total refill.

←

Well, ok. That tells us that a lot of fluid is trapped in the torque converter and can't simply be drained from the two plugs underneath. Mixing old, burnt fluid with new fluid is not proper maintenance. It would be comparable to draining half of the engine oil out every time you performed an oil change.

←

Here is the approach I use. Buy 25 qts of Type IV ATF. Drain and refill every week (or every other week) for 5 weeks. At the end of this campaign, you will have replaced 98% of the ATF. Yes, it takes some time. But, it is a relatively cheap and easy way to flush your system. If you back off to three changes instead of five, you will replace about 89%.

[lenore]

The U140E  tranny holds 8.8 quarts and the U140F tranny holds 9.8 quarts for total refill.

←

Well, ok. That tells us that a lot of fluid is trapped in the torque converter and can't simply be drained from the two plugs underneath. Mixing old, burnt fluid with new fluid is not proper maintenance. It would be comparable to draining half of the engine oil out every time you performed an oil change.

←

Here is the approach I use. Buy 25 qts of Type IV ATF. Drain and refill every week (or every other week) for 5 weeks. At the end of this campaign, you will have replaced 98% of the ATF. Yes, it takes some time. But, it is a relatively cheap and easy way to flush your system. If you back off to three changes instead of five, you will replace about 89%.

←

I guess that is still cheaper than a flush job, and Lexus doesn't have to touch it.

[mikey00]

I do like that method much better than a flush, but I think I will stick with my drain and fill every 15K.

[wwest]

At ~40,000 miles the ATF in my 2001 AWD RX300 looked and smelled burnt. I drained and refilled with 4 qts of ATF purchased at Lexus. About a week later the ATF again looked burned.

I discovered the diff'l drain plug should be removed and another qt could be drained. Back to Lexus to purchase 5 qts with an argument from parts manager that it only required 4 qts.

This time I dropped the sump pan and cleaned about 1/8 inch of non-magnetic ground up pencil lead looking debris. Installed the 5 qts which resulted in a very slight overfill when warm according to the dipstick.

AT 50,000 miles my ATF is now still pink like new. So no one is about to make me believe that this transaxle will hold more than 5 qts.

[lenore]

At ~40,000 miles the ATF in my 2001 AWD RX300 looked and smelled burnt. I drained and refilled with 4 qts of ATF purchased at Lexus. About a week later the ATF again looked burned.

I discovered the diff'l drain plug should be removed and another qt could be drained. Back to Lexus to purchase 5 qts with an argument from parts manager that it only required 4 qts.

This time I dropped the sump pan and cleaned about 1/8 inch of non-magnetic ground up pencil lead looking debris. Installed the 5 qts which resulted in a very slight overfill when warm according to the dipstick.

AT 50,000 miles my ATF is now still pink like new. So no one is about to make me believe that this transaxle will hold more than 5 qts.

←

Even If you drain the differential there is still 3 to 4 quarts lurking in the torque converter. Sorry, but the complete system holds 8.8 to 9 quarts. That is a fact.

Your cleaning the system is great though, don't get me wrong. I plan to do the same thing.

[RX in NC]

Yep, I always figured that my wife's vehicle holds between 8 and 10 quarts total. A simple drain-and-fill gets about half of that out, which should be enough to keep the fluid relatively clean every 15,000 to 30,000 miles.

These folks who believe their systems are running around with 16 or 18 quarts of Type T-IV fluid in them are woefully misinformed or ignorant, take your pick....

[monarch]

The dry fill fluid capacity of every Toyota / Lexus automatic going back to the 1960's has been at least 6.1 quarts and more usually between 7-10 quarts.

[Ericok]

EVERY automatic transmission leaves about half the transmission fluid in the torque converter when doing a drain and refill. The Lexus transmission is no different. If you want to change ALL the fluid out you have to do a flush or go the multiple drain-refill route. Toyota is adamant about using only Type IV fluid in this unit. With the history of this transmission, I absolutely would not use anything else. If you insist on not changing it regularly you must, at least, closely monitor the fluid condition (color, smell, level, etc.). Despite what Toyota suggests, I don't think you'll find anyone who'll say you can leave that stuff in there forever.

[wwest]

EVERY automatic transmission leaves about half the transmission fluid in the torque converter when doing a drain and refill.  The Lexus transmission is no different.  If you want to change ALL the fluid out you have to do a flush or go the multiple drain-refill route.  Toyota is adamant about using only Type IV fluid in this unit.  With the history of this transmission, I absolutely would not use anything else.  If you insist on not changing it regularly you must, at least, closely monitor the fluid condition (color, smell, level, etc.).  Despite what Toyota suggests, I don't think you'll find anyone who'll say you can leave that stuff in there forever.

←

Keep in mind that modern day torque converters are a lot smaller that their older brotheren. In today's cars the clear majority of the time the lock-up clutch is engaged and the torque converter does absolutely no work. I would be very surprised if modern day torque converters have an ATF capacity much greater than one quart. So only 1/2 quart, at most, would be left after draining.

[bluestu]

Well, at least we're almost all in agreement that the transaxle holds a bit more than 5qts, and that synthetic fluid is a must, preferably TIV. Stick with the drain and fill if you must, but I prefer the flush because it totally cleans out the entire transaxle. It's like starting from scratch with a clean transaxle and refilling with all new fluid. I bought my RXs used and have had three flushes on each one, and the transmissions are much smoother and quieter than when I first bought the cars. They shift like a new car would. No joke.

I do agree 100% that if you live in a region where you don't need an AWD, get the FWD version if possible. You're less likely to have problems if you perform proper maintenance, and you'll get better gas mileage.