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"...extremely concerned about gas mileage....." ME...?? You're reading my statements completely out of context. My concern was not so much about gas mileage but about the compromise of HP vs fuel economy that was being made with regards the RX400h design. "...adamant about buying the best handling SUV...." No, there were lots of SUVs that were better "handling" than the 2000 AWD RX300 and then an even better selection when I traded up to the 2001 AWD RX300. Life is about compromises. Additionally I do like to tinker. My RX300 even has a custom microprocessor installed between the climate control ECU and the mixing vane servomotor. The custom microprocessor continually "watches" the position of the system outflow control servomotor feedback potentiometer and if it "sees" it moving "toward" the defrost outlet position it "inserts" a false feedback indicating the outflow position is already at defrost. If the servomotor then begins to reverse then we know the destination wasn't defrost and we back out of the control loop. On the other hand if the destination was/is the defrost outflow position then we immediately begin moving the mixing vane servomotor to the full HEAT position via falsifying its feedback. At the same time we directly command top speed for the blower motor. So now by the time the system outflow servomotor has finished moving the outflow controls to the defrost position the blower is at full speed and the heat level has been turned up to HIGH. While all of this is going on we have also biased the IAT, internal air temperature sensor, to make the OEM ECU "think" the cabin is suddenly grown quite cold. As a result of digital signal processing the OEM ECU will not fully react to the sudden large change in the IAT signal for about 30 seconds. After it does the OEM ECU will begin to command full heat and high blower and our ECU will then drop out of control except for maintaining the false biasing signal of the IAT sensor. A digital potentiometer is mounted on the dash so the driver can readily downward modulate/control the windshield blower and heating level as long as the system is left in the deforst position. In my 1992 LS400 this task was much simpler since the OEM ECU would instantly respond to a sudden large change in the IAT signal output. All I had to do in the 92 was have a simple STSP switch that I flipped just before switching the system to defrost/defog/demist mode.

Just call me John Kerry.

Sorry, the ownership/management at a Lexus dealer values the bottom line just as much as their counter-parts at Jiffy Lube. Maybe even moreso given the cost associated with maintaining an upscale image. Next time your Lexus is in for just simple, routine maintenance of some kind find a way to observe who works on your car.

Trying to come to the next purchase decision myself. Right now the new Acura RDX is in the lead due to the dynamic front to rear and rear side to side engine torque allocation. Just don't like the cluttered look of the dash/intrument panel. The AWD RX400h appears to dynamically allocate engine torque front to rear but still uses Trac braking for side to side torque "forcing", LSD "virtualization". Until I actually get to drive an RDX the RX400h certainly seems to have the best overall VSC/Trac system. Confusion factor is that the new RX350 has the VC again making it possible to convert it to rear torque biasing with a slight modification of the center diff'l. But luckily I don't need to be in any hurry to make my decision, I will certainly wait to test drive the RDX and possibly even wait to see the 2007 RX400h in the fall. If it helps any at all, if I had to make the decision right now it would be the AWD RX400h

Bad news, really bad news. Routine maintenance does require any level of skill. So it doesn't matter where you go or how much you pay, it will be a McD "flipper" graduate doing the routine, scheduled, maintenance on your vehicle. I'm not sure just what I would do were I not a DIYer. On second thought... My Porsche goes to a small but upscale and elite two man shop. Expensive for an oil change but no gofers about.

The RX400h uses DBW(e-throttle), BBW, Brake By Wire, and EPS, Electric Power Stearing. The EPS via "cooperative control", is integrated with VSC and will therefore actively RESIST turning the stearing wheel in a direction that would lead to exacerbating a VSC activation circumstance. EPS will actually RESIST turning the stearing wheel at all during hard acceleration. I would whole-heartedly recommend that anyone considering an RX400h or HH purchase subscribe to http://techinfo.toyota.com and read up on the VDIM sections thoroughly

"...evolved design....??" In a "back to the future" sense, yes. As of 2004 the VC, viscous clutch/coupling, mounted across the center diff'l's two output shafts in the earlier RX300s, was abandoned. At the same time the difference in the final drive ratios of the front driveline versus the rear was actually increased to farther "natively" bias the torque to the front. Dynamic torque apportioning upon front wheelspin/slip was left entirely to the use of braking and dethrottling. Now here we are with the RX350 with the VC again in use and a return to the final drive ratios of the RX300. What gives...?? We all know, or should know, of the too early ATF "contamination", burned and darkened at less than 40,000 miles, and the apparently resulting premature, ~70,000+/- miles, transaxle failures of the RX300 series. My guess is that the VC in the RX300 became such a great source of heat during actual front wheelspin/slip operations that it caused localized heating of the ATF via heat transfer from the PTO case to the center and front diff'l case. The question becomes is what was changed in the interim to allow the use of the VC again??

Since the "torque sensing", viscous fluid, in the center diff'l is hermetically sealed within the clutch(LSD) case I doubt anyone would suggest replacing that. THat leaves us with the lubricating oil for the PTO assembly or the 2000 and earlier rear diff'l and optional mechaincal LSD.

The RX300 used a viscous clutch/coupling across the center diff'l along with overdriving the rear driveline in order to have a "full-time" AWD system that required no interaction of the driver. With the introduction of the RX330 the overdrive level of the rear driveline was actually increased although the VC was dropped entirely. Now I see the new RX350 has the VC again..... And the F/R final drive ratios are back to those of the RX300. We have all heard stories of the early, premature, transaxle failures in the RX300 series and I can vouch for the fact that something unusual is causing the ATF to be compromised long before the factory estimated it would need to be serviced. At 40,000 miles the ATF in my AWD RX300 was smelling burned and looked brownish although the manual indicates no ATF service is required for the life of the transaxle. You may notice that the PTO, power take-off assembly/case has lots of heat disapating cooling fins on the exterior. The way the VC works is that the viscous fluid is quickly heated whenever there is a disparate rotational rate between the front and rear drivelines and being hermetically sealed it cannot "expand" so the result is compression, thickening, of the viscous fluid. Obviously this heat must be "wicked" away fairly quickly and rapidly in order for the center diff' to return to its normally "open" state once the wheelspin/slip has abated. Thus the numerous cooling fins on the outside of the PTO case which contains the VC. But. What if it was the heat from the VC, transferring through the metal "wall" separating the PTO and the diff'l case that was overheating the ATF beyond its normal operating temperature? Does the PTO in the RX350 have better heat "disposal"??

Unfortunately, this could significantly reduce the life of your batteries. Toyota knows that the batteries that are used (NMH), like the standard lead-acid battery, last longest when they are not discharged past an ideal percentage range of full. Even marine-type (deep-discharge) batteries like the Optima Yellowtop rarely live past three years, compared to 5 years for a standard auto battery. Maybe if a complete set of batteries for a hybrid could be purchased for $300, you wouldn't mind replacing them every 4 years of deep-discharging, but this is not the case. I'll keep my 25 MPG and a battery lifespan of 10 years, thank you. Anyone else considering a tow-along genset?

The 3.5L V6 in the RX is not the new DFI 3.5L V6. For anyone truly requiring AWD I would suggest waiting for the new Acura RDX with SH-AWD. Instead of SH for Super-Handling it should be FO-AWD for fully optimized. Or maybe SH/FO-AWD.

Tire chains only on the front of any vehicle can quickly turn an already nerve-wracking drive into an extremely HAZARDOUS one. Just as your Lexus owners manual warns, extraordinary traction on the front versus the rear can, and often does, lead to loss of directional control, especially on a slippery downhill run if you need to suddenly slow or brake quickly. I added 1.5" wheel spacers all around on my 2001 AWD Rx300 so that I could use tire chains safely, on the rear first and then also the front if the need arises. Both sets went with me this past weekend from Seattle to Dayville OR. Luckily the only adverse roadbed conditions we encountered was a heavy FRESH snowfall, maybe 6 to 8 inches, on the pass just south of Fossil.

The defaulf, OFF, position, settings, of the Toyota/Lexus automatic climate control system is with the blend door in the heat position. Until the engine coolant warms or you actually turn on the fan the airflow routing will be toward the windshield, "baffling the incoming airflow, defrost/defog/demist position. This latter is to prevent you from being hit with a cold blast of air from forward motion when you first start out on a coldish morning.

Personally I'd take your 300C and a good set of quick install snow chains long before any AWD that is natively FWD as is the 2001 AWD RX300. I just drove mine from Seattle to Dayville OR, luckily no snow that "stucK". But mine has 1.5" wheel spacers all around with 17X8 wheels and wider tires. I always run on summer tires and rely on tire chains, on the rear first and then added to the front if needed. Tire chains cannot be used on the rear of RX series as shipped, thus the 1.5" spacers. The 2001 AWD RX300 is natively front torque boased about 95/5. They use differing final drive ratios in the front vs the rear so the rear wheels are overdriven by about 5% which matters not as long as the center diff'l remains open. Once the VC begins to "lock" the center differential the rear starts to take up the torque "slack", about 75/25 F/R at best. Be careful, the FWD/AWD RX300 can get really dicey on the slippery stuff.

I would wholeheartedly agree that tread rubber compounds can make a significant difference in traction levels of winter use tires vs summer. That being said, stated, I will be the first to say that was all in years, many years, gone by. Back in 1963 you could even buy winter tires that had walnut shells embedded within the tread rubber to improve traction on ice or packed snow. I'll let you guess how many winters it took, even in MT, to wear those out. And that's where your argument falls apart. These days the level of "guarranteed" mileage the manufacturers state for summer tires is much the same as for winter tires. Some of that is accomplished by having deeper tread blocks on the winter tires but in reality that only makes up for the mileage loss due to having less surface contact area on the winter tire to begin with. So, the question to you is, "If today's tread rubber compound is different for winter tires vs summer tires how can the mileage "life" be the same?". Yes, I know, agree, that if what you say is true, "the soft rubber will harden with cold but not to the level a summer tire would/will", and given that the majority of the time these winter tires run on only wet or dry pavement, how can that be? And by-the-by, the only motorcycle racing I have ever witnessed in the type of conditions discussed here was on a frozen lake in NH and I seem to remember the motorcycle tires had some serious traction SPIKES punched through the tread area. "....but how often do you drive on an ice rink?..." My point exactly. Not often enough to justify switching to winter tires ALL WINTER, which is why I feel tire chains are a much better solution overall. I don't think anyone will question that tire chains offer a phenominal level of traction on ice or packed snow as opposed to ANY winter tire. Not by any means saying that proper tire surface and compounds aren't EXTREMELY important in the racing venue. As with everyone else, our race team uses electric "blankets" to keep the tires warmed when not on the car.

I am very interested........... Do you know if it has the memory feature??? Which my car needs... Thanks Mark The 2004 d/s mirror just arived, it is black, and the connector has 14 wires. You started out by saying that only the mirror was broken, are you aware that the mirror is removable/replaceable from the rest of the assembly? Do you know how to remove my broken mirror and replace it using the glass part from your Mirror??? Thanks Mark Not at this exact moment but I do have the Lexus shop manuals for the RX330 so I can look. I'll do that on Monday.

Keep in mind that traction control will time out after about 45 to 60 seconds of semi-continous use. All of the VSC/Trac{LSD/AWD}/BA/EBD functionality is based on the ABS pumpmotor's ability to pressurize and replenish the brake fluid to the capacity of its useage. The ABS pumpmotor is a fractional HP 12 volt DC motor roughly the equivalent of your windshield wiper motor. More than about ~45 seconds of operation at this torque/load level and it will overheat and fail. Once the ~45 second timer disables the ABS pumpmotor it will take at least one new drive cycle of about 100 yards (2001 AWD RX300) before it will again operate. And personally my RX rides on nice quiet and comfortable summer tires all the time, all year around. For the fairly rare exceptional times I need traction on slippery surfaces (NOT LOOSE SNOW) I keep at least one set of tire chains on board. Today we're leaving for Dayville OR and the second set will go in the tire well before we leave. "Winter" tires only help if the surface is such that they have bite, can dig into, the surface. They are no help on packed snow or ice. Summer tires, with more surface contact, less siping, will always have more grip on a solid surface, even a slippery one. Be all that as it may, my chains go on the instant I discern a shortcoming in adequate traction.

All the way back to the traction system on my 1992 LS400 I had to learn to religiously turn off the trac system each time I started the engine. Otherwise it would sometimes leave me with a totally dethrotthed engine in the front of oncoming traffic. Traction control is definitely a good feature as it will often save your butt when you hit a slippery spot of which you were, would have been, otherwise unaware. But. It can also be a damn nuisance. Any time Trac activates it will apply braking to the slipping wheel(s) to prevent or alleviate wheelspin. At the same time most trac systems will also simultaneously dethrottle the engine to prevent overheating of the rotors and subsequent warping. But there are times when a little wheelspin, maybe even with some back and forth rocking, can be a definite advantage, as in getting unstuck initially. There are also times when the driver can be slightly more judious via feathering the throttle to get going than can the Trac system. So yes, there are, can be, times when it is definitely advantagous to be able to turn off the Trac system. With VSC I'm not so sure. Porsche's PSM, their VSC equivalent, can be turned off if/when the driver expects to be doing some exceedingly sporty driving. But it will come back on the instant the brakes are used. Obviously when ABS activates it can be, is a heads up that the braking level you're asking for cannot be supported by the available roadbed traction coefficient absent the threat of loss of directional control. Trac activation, in the same way, is a heads-up that the rate of acceleration, or drive even, that you're asking for via the throttle application cannot be supported by the available traction coefficient. While on a RWD vehicle the driver can still maintain direction control with the driven wheels slipping that is NOT true of FWD or front biased AWD. So, in general, dethrottling of the engine on a FWD will always be much quicker, virtually instantaneous, vs a RWD or rear biased AWD. Some RWD vehicles actually have a discernable delay in dethrottling, giving the driver time to react and feather the throttle, when rear wheelspin develops. I have driven my Porsche on the track at Daytona, literally as fast as I was comfortable going, 130+, but I did not bother to turn the PSM system off. Porsche's implementation of stability control is different from most in that it gives the driver a few hundred milliseconds to react and crank in corrective measures. Obviously that would not be a good idea for the driving public at large since very few would have the driving experience or knowledge, or in some cases not even the ability, to react correctly. For instance if a RWD vehicle with manual transmission begins to overstear the proper procedure would be to quickly depress the clutch and counterstear into the direction of the skid. FWD vehicles are not very subject to overstearing, they more often understear. The VSC in my front biased AWD RX300 will apply both rear brakes if understearing is detected, the idea being that the rear wheels have not lost traction and therefore can be used to slow the vehicle, hopefully to the point of the front wheels regaining traction. Absent VSC the only thing the driver might do to combat understearing is to counterstear and/or apply the parking brake judiously.

No, the new 3.5L V6 with DFI is the new engine, the one in the RX350 is simply a bored or stroked 3.3L.

Regarding the sludge issue Toyota supposedly made a small change in the engine block to alleviate the oil sludging problem in newer engines. But now I notice the new RX350 has an external engine oil cooler (almost unheard of otherwise) so I'm not so sure the earlier fix actually worked.

Your X5 was rear torque biased while the RX series is front torque biased. A totally differently "feel" dynamically driving style wise. The first thing you will notice in comparison is that when you get/got off the gas in the X5 the result was a serious level of engine compression braking. Ther RX series, being predominantly FWD or front biased AWD will quickly upshift in this circumsatnce to alleviate any substantial level of engine compression braking on the front wheels. If you live in an area wherein you occassionally need to use tire chains the previous RX models could not have chains installed on the rear due to poor suspension clearance. While on the one hand warning you about the hazardous of an inordinate level of traction at the front versus the rear the owners manual that goes forward to tell you to use tirechains ONLY on the front. Were I you I would check out the newer style/design AWD systems in the following vehicles before I leap from a marque dominated by RWD designs, BMW, into a mostly FWD vehicle. Volvo XC90 Ford FreeStyle Lexus GS300 Lexus IS300 Honda Legend Acura RL Acura RDX While I own a 2001 AWD RX300 I would personally wait to test drive the upcoming Acura RDX SUV before taking delivery of an RX350. The new RX350 is again fitted with a viscous clutch so it can have infinite levels of "lock" on the center diff'l so in the end I may buy one, but not before a shakedown cruise in the RDX. The RX series is really truly one beautiful and relaible SUV, but if you need true AWD capability the solidly rear torque biased X5 or X3 will run rings around it.

Well "duh". "Run circles around it" is a figure of speech, RX in NC knows how a vehicle operates in the snow and the physics behind it I'm sure. He wasn't suggesting he could literally drive a Jeep in a tight circle better than an RX. He meant the Jeep would out perform the RX in snow driving. ------------------------------------------------ Sorry, you missed my point entirely. I never said the RX was equal, or not, to anything. What I said, or was trying to get across, was that a RWD or rear biased AWD ( a modified RX) would likely OUTPERFORM his 4X4 Jeep using a locked center diff'l in overall adverse conditions. Just how many of us would willingly chose the ability to accelerate more rapidly, or at all, in averse conditions, in favor of the possibility that that choice might result in loss of directional control? How many of us have witnessed 4X4s being overdriven and ending up in the ditch or worse? Rear biased AWD is undoubtedly one of today's wonders of technology. Those on the below list are even ahead of that benchmark. ------------------------------------------------ And what exactly is it that these vehicles have in common? All of them dynamically and automatically reapportion engine torque to the rear, away from the front, when front traction is best allocated to lateral, directional control.

Tell you what though, you take your Jeep in 4X4 mode, locked center differential, and run the tightest circles you can on a slippery surface of your choice and I will then take the very same Jeep in 2WD/RWD (assuming it has one) and either run tighter circles at the same speed or the same radius at a greater speed. I would even challenge you with your own AWD RX300 if you gave me permission to convert it to "direct" RWD and only the viscous coupling to the front. Driving all four wheels only helps for acceleration. Having engine drive torque to the front wheels while going in circles at a constant speed is actually detrimental to performance in that situation. Dedicate the front tires roadbed adhesion coefficient strictly to lateral, directional control, and stearing capability, response, improves dramatically on a slippery surface. That's why we're seeing so many new (***) AWD systems that dynamically re-apportion torque according to the circumstances at hand. The new Honda/Acura SH-AWD system can even apportion torque side to side at the rear to help prevent the understearing FWD vehicles have otehrwise always been famous for. Volvo XC90 Ford FreeStyle Lexus GS Lexus IS Toyota 4runner Acura RL Acura RDX Are there others?

I am very interested........... Do you know if it has the memory feature??? Which my car needs... Thanks Mark The 2004 d/s mirror just arived, it is black, and the connector has 14 wires. You started out by saying that only the mirror was broken, are you aware that the mirror is removable/replaceable from the rest of the assembly?

I agree, it does sound like ABS kicking in. Other cars like Honda or Acura tend to be more rough in their ABS, but luxury cars like lexus and bmw tend to have such a rapid-fire ABS, that it almost feels like a vibration. I have an 06 RX330 and in my opinion, I think the awd is great For those of you that thought your RX330 had full time AWD you might take notice that the newly available RX350 heralds the return, encore, of the VC, viscous clutch/coupling within the PTO so that the center diff't can exhibit at least some semblance of "lock". It also looks as if maybe the modification to the engine to prevent further episodes of oil sludging may not have worked as well as it might have. The engine in the new RX350 now has an external engine oil cooler.