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Okay, done deal. Drained pan and diff'l case. If anything the fluid I drained was even worse, darker in color, than the first batch. Didn't smell as burnt though. The darker color may have been the result of draining it cold this time. The last time I ran the car first on the assumption that particles, debris, would remain in suspension long enough to drain them along with the fluid. The bottom of pan was covered with ~16th of an inch of what looked to me like powdered pencil lead. Three flat magnets stuck on the inside of the pan and none of them including the diff'l plug maget had an undue level of metalic particles attached. No new answers I guess.

"longest waiting list in the history of Lexus..." Yes, and how much of that wait was due to Lexus delaying production again and again? How many do you suppose lost faith and dropped off the waiting list. Must have been very close to the 18, 000 Lexus touted as being on that waiting list since so many high population density area dealers are now offering first come first serve MSRP deals on the RX400h.

Solenoids alone aren't necessarily the primary delaying factor. It's more likely the valve body hydraulic sequencing along with the actual time it takes to release the clutches from the previous gear ratio, give them time to actually fully release, hydraulic pressure to bleed off, and then "order" the proper set of clutches for the new gear ratio to be engaged, pressurized, and the wait for them to be fully engaged. Think of the time it takes with a stick shift, assuming you want your manual clutch to have a long life. Get off the gas, and disengage the clutch (unlock the torque converter) take the shifter out of the previous gear (release the hydraulic pressure on the clutches for the previous gear and wait for the "return" springs to force them open.), slide the stick into the new gear (pressurize the clutches for the new gear ratio, and wait for them to engage), release the clutch pedal and apply appropriate pressure to the gas pedal (heavy gas pedal pressure, or closed throttle, leave the torque converter unlocked. Gas pedal positioned for cruising, lockup the torque converter). "-Why did/does the 4-speed auto not have this issue..." I have argued that it actually does. But in a different "form". I have no doubts whatsoever that the transaxle in my RX upshifts if the throttle is fully closed during highway coastdown and just before coming to a full stop. When it does and I re-apply pressure to the gas pedal it must now downshift. The transaxles in the previous model, the RX300, seem to be failing prematurely at an unusually high rate. I have reported that the transaxle fluid in my RX was burnt and dirty looking at 38k miles and apparently Lexus has revised the recommended maintenance schedule from NONE to every 15,000 miles to address some here-to-fore unknown flawed operational aspect of these transaxles. My RX has a mechanical throttle connection so the throttle valve cannot be closed during a transaxle shift sequence. Can Lexus temporarily "detorque" the engine some during the shift sequence? Stop the ignition ? = RAW gas & air mixture into the exhaust stack and catalytic converter. Disable the fuel injector power? = PURE oxygen to the exhaust stack and catalytic converter. Considering the EPA's and CARB constantly changing, updated, emission standards are either of the above choices viable. What are their long term effects on the oxygen sensor and/or the catalytic converter. Suppose the firmware in my RX series, with an engine that cannot be dethrottled for 1 to 2 seconds, doesn't have an embedded wait delay to be sure the previous gear ratio clutches are fully released before engaging the next "set". That would result in BURNT clutch frictional surfaces, burnt and "dirty" looking fluid, and eventual failure of those clutches. What's the most economical fix to prevent premature transaxle failures in the newer models? DBW.

I was simply pointing out that the service writer would have little motivation to earn a quick commission for selling something in stock, unlike what some have said would be the case if a saleman had said this. "Limited production" "Nothing in history" One can also say that Lexus has NEVER encountered the number of product delays nor the duration of those delays as has occurred with the RX400h. And I think you could say the SC430 has had a "limited" production run. Making an announcement that the RX400h will be "limited production" would be an easy way of "saving face" for the embarrassment of non-public acceptance of a hybrid gas hog.

"it would take 1.7 years to recoupe..." How long does it take if the choices are that I either stick with my 93 Ford Ranger with I4 and manual transmission vs trading up to the RX400h? Or what if I trade up from my 2001 AWD RX300, how long does it take to recoupe the actual FULL tradeup cost? Looking at just the value of fuel savings isn't nearly the FULL picture.

Sorry, too many HONEYDEWS....

Mixed bag.... Those of us who want to be environmentally conservative, "greenies", likely will not be buying any vehicle being marketed based on V8, hybrid SUPERCHARGED performance. So the market will most likely be "boy-racer" types that want to "look" green. How many of those around?? And given the vehicle is being primarily marketed to "lead-foot" types, that Boston Lexus service writer may very well be correct, the RX400h will be a gas hog, not as a result of the hybrid aspects, but because of its use in the designated high performance market.

Hey, according to the post that was the SERVICE WRITER that said the RX400h would be a gas hog, not a saleman. And from what I read each dealer is getting one, exactly ONE, RX400h demo version on the 20th of April and actual sales have been delayed until sometime in May.

"0-40 MPH without using ANY gasoline..." That statement reminds me of the time our governor, Dixy Lee Ray, put her foot in her mouth by saying, with regards to saving water... "Electricity can't be stored..." So, RX400h, just how do you think those batteries got charged, or was it a form of Keebler's Magic Oven? Or was it from the inertia created by gasoline and/or the ICE being used directly to charge the batteries. "Official EPA ratings...." Please don't be insulted but would you mind referencing the actual publishing source?

Has anyone seen any OFFICIAL EPA cty/hwy mileage ratings for the RX400h? Like directly from Lexus? The Lexus mechanic in Boston seemed to be saying MPG for the RX400h would be poorer than the RX330... I guess you have to give up something for V8...Zoom, ZOOM,....ZOOM!

Okay, first, how many, if any, RX330 owners have experienced the "bumped from behind" symptom just before coming to a full stop, or the "slingshot effect" during coastdown, throttle closed, from say 30-50MPH? If the answer is none then just ignore the following. My 2001 AWD RX300 exhibits both of the above symptoms. The seat of the pants "feeling" of both of these symptoms is as if the clutch were just disengaged with a manual transmission. I have two theories as to why this is happening and neither of them, or one, or even both, may be the actual case. Theory one is that the transmission is being upshifted to reduce engine braking, allowing the vehicle to coast farther and thereby increase fuel economy. Theory two is that the vehicle is being upshifted just before coming to a stop to prevent potential loss of control due to engine braking at the front wheels on a possibly icy roadbed. Think about this. If you were driving a FWD vehicle with a clutch would you EVER downshift to use engine braking on an icy roadbed? Yet don't we fully expect a FWD's automatic transaxle to downshift into first as we slow to a stop. Personally I think the designers have made a wise choice here, they have no way of detecting the roadbed conditions as you come to a stop so the best action on their part is to write the firmware to provide an upshift ("disengage the clutch to prevent loss of directional control" ) when slowing to a final stop and only shift down into first once the vehicle is FULLY stopped. As I have already said, if your RX330 doesn't have the above symptoms then it is needless to read farther. But if the firmware in the RX330 engine and transaxle ECU is doing the same thing as my RX300 then I can see how that might lead to some serious indecisiveness on the part of the firmware. The firmware initially detects a coastdown situation, brakes on or not, but the gas pedal fully released, so it begins the upshift sequence. Now you start "dithering" the gas pedal because you're being indecisive about whether or not you can accelerate quickly enough to safely merge into the opening in the adjacent freeway lane. According to the firmware the transaxle hasn't yet completed the upshift sequence and now you're giving it mixed signals, dithering the gas pedal, about what it should do next. According to the shop manual the transaxle servo system's feedback, the way it tells when and what gear ratio the transaxle is actually in, is via comparing the transaxle's input shaft speed with/against the output shaft speed. In other words it commands a certain gear ratio via electrically actuating the appropriate solenoids and only knows that if the commanded shift is complete when/if the computed input/output ratio indicates that it is. And what if your own indecisiveness, your "dithering" of the gas pedal, is confusing the firmware with regards how far to downshift? Remember that once the ECU commands a downshift, say into 3rd, that "shift" must be verified to be completed via the input/output computation. So the shift into 3rd has just begun and you relax the pressure on the gas pedal ever so slightly. Oops, the firmware now decides you should only downshift into 4th. Oh, my RX300 only has three forward gears plus OD so there is not as much "opportunity" for the firmware to be indecisive!

That statement by hybev1 wasn't related to EPA figures, it was related to an RX400h against the RX330! As many have said before me, you can't draw blood from a turnip! You can only generate so much power from braking in city traffic, and only a fool would use coastdown inertia to generate power when the brakes are not applied. And it takes an even bigger fool to use the ICE to generate power to charge, and recharge, and recharge, etc, etc, the batteries during highway cruise. That's why the highway MPG is so low. Any engineer worth his salt would simply charge, top off, the batteries and then not use them again as long as a reasonably constant speed were maintained or maybe if WOT is applied.

What Lexus said in an email to me in response to this question was that the RX330 is 50/50 when traveling at a constant speed and all four tires have roughly equal traction. What I have determined for my own satisfaction is that under acceleration the torque split is more on the order of 90/10 F/R. Now Since I have a 2001 AWD RX300 I cannot speak for the RX330 but with my RX300 if the front tires lose traction the engine is almost instantly dethrottled and the front brakes at applied to maintain a high level of engine torque once the VC does its job (if it ever actually does). Remembering how potentially hazardous it can be to lose front traction (no directional control) due to engine torque application I think it is entirely appropriate to quickly dethrottle the engine while simultaneously using the brakes to maintain and apportion engine torque to the rear. Your vehicle's Trac system also uses the brakes to simulate a rear diff'l LSD and maybe a front one too but I'm not so sure about the front.

Hey, if they can't get the technology down correctly in the RX330's engine/transaxle ECU, what makes you think the RX400h will be an improvement? That's not your father's (Prius) hybrid system you know. I think I'd trust Ford and Toyota to get the Escape correct before I'd try Toyota out on the RX400h. The Escape does have your father's hybrid system. And think about what might have been behind, the cause of, the RX400h's two year production delay.

Check the transaxle fluid condition IMMEDIATELY! Many RX300 owners are reporting premature Transaxle failures, most seemingly on the order of 50,000 to 70,000 miles, some as early as 15,000 miles. While there is no recommendation in your owners manual for scheduled flushing and replenishing of the ATF the factory is now saying they recommend 15,000 mile fluid change-outs.

Funny you should mention that... When I drained the first batch I filled two half-pint glass jars with the burnt fluid, "mid-stream". They are still setting on the windowsill of the garage at the moment because I assumed some of the "debris" would settle out over time. None has. So yes, I need to find a lab. In the meantime, tomorrow, the pan will get dropped after I drain the transaxle AND the diff'l!

I may.... It appears that Toyota/Lexus cannot, will not, provide a fix for the engine hesitation problem. My suspicion is that a true fix cannot be provided without compromising the CAFE or CARB regulations and standards under which all of these FWD V6 engined vehicles were shipped. If that is indeed the case then it is likely that no fix will be forecoming from the manufacturers. So there may be an opportunity for an aftermarket product if one can find a solution to getting, or keeping, the transaxle into the correct gear.

So, the front and center diff'ls are an integral part of the transaxle and run in ATF. The PTO (Power Take Off), right halfshaft, VC (viscous clutch), and tailshaft ring and pinion run in ~90 weight gear oil. Two oil seals to keep the two oil volumes separated. Suppose the oil seals leak slightly and the gear oil, over time, contaminates the ATF. Or even more likely... The VC operates by heating the viscous fluid sealed within the VC case. In due course the heated case of the VC will heat the gear oil and cause it to expand and with enough volume will force its way into the ATF side. ATF contaminated with 90 weight gear oil cannot be a good thing. Are more AWD transaxles failing prematurely than FWD?? Is that why, maybe, the VC was dropped in 04?? 90 weight gear oil is very close to the color, very dark, of the stuff I drained from my transaxle except for the slight red tinge.

THE ANSWER! We were both right....sorta.. But mostly I WAS WRONG. The front and center diff'ls are a part of the transaxle and run in ATF. The PTO (Power Take Off), the right halfshaft, and the VC run in gear oil. An oil seal around the right halfshaft separates the two volumes. So you, and the dealers, are correct in that the diff'l drain plug should be removed and the fluid drained from there also. Thanks for catching that for me before I "wasted" another 4 quarts.

First, I was so unsure of myself I had one of my engineers crosscheck the information in the manuals. I know that the rear differential runs 90 weight and had assumed that the "front" one did also. And I have no doubt of what the shop manual states...before beginning work on the front diff'l.... 1. Drain ATF 2. For U140F Drain gearoil This is from memory so its probably not exacting. U140F is the AWD transaxle. Also in looking at the pictorial representations of the transaxle vs the front differential case there isn't any obvious channel for interconnecting fluid flow. Have we somehow stumbled on how and why these RX transmissions are failing. Dealers are draining the 90 weight and not replenishing it? Thinking that in filling the ATF they're replenishing the diff'l lubrication? I will check the manuals again when I get to work this morning.... I did use the 2001 manuals yesterday except for the separate transaxle shop manual but only referred to that for pictorials. Because I first owned a 2000 AWD RX300 I also have the 2000 shop manual set and will see if they differ. When I went to buy the 2001 set I was told that the separate transaxle volume had not changed so I could continue to use the 2000 volume. Worrisome, very much so.

RX in NC... Boy did you PANIC me! Now my turn?? "remove the differential plug..." My first thought was "how could I have missed that?". But then I went and checked the Lexus RX300 shop manuals... QUITE thoroughly. The FWD RX300's differential runs in transmission fluid, ATF. The AWD RX300's differentials, front and rear, run in 90 weight. I hope you haven't drained the 90 weight from your front differential...?? But if you only cleaned the differential "plug" and the two systems are fluid isolated I don't see how that can help. What have I missed?

If you mean the plexisglass outer covering the color "tone" is to block the UV rays generated by the HID arc. Ever see a welder with a really bad sunburn??

No, not bad at all....

With the RX V6 they are behind and below the intake assembly.

NO.