Lexus RX AWD vs FWD Questions

fry2fry2 Member Posts: 3
Purchased a RX 350 AWD, 2008 in January. Only 2K miles now. Recently some noise problems appeared. While moving out the car from garage in the morning. Gear in reverse, Loosen the brake pedal. Heard the detaching noise from the brake pad. Shifting the gear from R to D, noisy "Goo Goo" sound.

Visited 2 dealers. The first said it is normal for this SUV. The second said new car always has lots of sticky chemical under braking pad. Releasing the pad or changing gear may cause noise. This should be gone after more driving miles.

I am not convinced by both dealers. I talked to friends who own this SUV and they don't have this issue. This is a brand new Lexus! I expect it to be perfect.

Any opinion or comments? Thanks a lot.

Comments

  • jacks2jacks2 Member Posts: 45
    Drove approximately 130 miles in moderate to heavy snow and iced roads with very little slippage. Off road I drove through snow 8-12 inches deep without a problem.
    No change detected in performance using the snow selector switch. The RX held it’s own as compared to other 4wd vehicles in my group.

    My only criticism is the lack of an emblem indicating AWD as I was stopped in a “chains required” area by the Highway Patrol and had to explain it was in fact an AWD vehicle.

    I’m curious, has anyone else been stopped for not having chains and how did you prove it was AWD? Fortunately I still had the window sticker in the glove box.

    J2
  • calculuscalculus Member Posts: 6
    That's it !!!.
    Thanks for the tip. I will just keep my window sticker in
    the glove box in case of "emergency".
  • jacks2jacks2 Member Posts: 45
    I wasn’t able to find any other documentation in the glove box to show this was AWD and pointing to the “snow button” was unproductive. I’m looking for “A,W,D” magnetic chrome letters to place under RX350. :)

    It seems like every other 4WD / AWD vehicle I saw that day had badge indicating it.
    I’m open for suggestions other than carrying a dozen crispy cream donuts. :D
  • ca2nyca2ny Member Posts: 3
    Can anyone advise me how to distinguish an AWD RX330 (model year 2004) from a FWD one? As far as I can determine, there are no differences in the badges on the car, nor does the manual appear to describe any readily visible feature present on the AWD model that would be missing on the FWD model (or vice versa). Short of taking it into a mud hole and seeing which wheels spin, how can I identify whether the vehicle is AWD or FWD?
  • avery1avery1 Member Posts: 373
    I believe there are certain letters in the vin that indicate FWD or AWD. Unfortunately I don't know them.
  • la4meadla4mead Member Posts: 347
    I'm guessing (based on the RX300?) it's the fourth digit of the VIN: G for 2WD, H for 4(A)WD, however I don't know for sure on your model. Kelley Blue Book or NADA might help, and you can access them online.

    The most sure way is to look for the driveshaft/rear differential under the car. Even if not mechanically inclined, if you can look and you don't see a way for the mechanical transfer of power to the rear wheels from the transmission, you have 2(F)WD. In other words, if you do have AWD, there will be a drive shaft (black, about 2" diameter) going through the center tunnel (next to the exhaust) from the transmission to a (differential) gear box (about 12" square) distributing between shafts going to the rear wheels. If it's empty of driveshafts, to and in between the rear wheels it should look like the middle of the car only has an exhaust pipe, but no shaft.

    I hope it helps.
  • ca2nyca2ny Member Posts: 3
    Thanks for the explanation of what to look for. Even I (non-mechanically inclined, as you correctly surmised) ought to be able to tell with that clear description.
  • la4meadla4mead Member Posts: 347
    Although this doesn't need a separate thread, I'll take a stab at it and suggest you might be hearing any of the following, especially considering how little you use this car (sitting a lot or short trips is severely hard on any car).

    You might be hearing any of these:

    1. The sound of the brake pads "hooking up" and "unhooking" for the first time after R-D shift.

    2. The hydraulic sound of the ABS pump priming for the first time after the car was started and moved forward.

    3. The hydraulic sound of the transmission pressurizing.

    All are perfectly normal sounds for this or any car. You may notice it more in the RX because it's unusually serene for a car of it's type, but not built to the same refinement as a $60,000 + sedan.

    How perfect would you like it now that you've had it long enough to notice subtle noises? There might be others but these are my guesses from what you've said.

    I hope you enjoy your car...
  • prikprik Member Posts: 5
    Hi,
    Apart from the dealers words, is there any way to know if my rx350 is AWD? Normally, on few suv's they mention it on the vehicle as "AWD" if it's an All-wheel-Drive, but Lexus doesn't.
    Is there anyway to check if my Lexus is AWD?
  • prikprik Member Posts: 5
  • la4meadla4mead Member Posts: 347
    Personally, I applaud the lack of stuck-on badges and graphics. But if you didn't buy the vehicle new (check your window sticker) then check your VIN. I'm not sure about 350 models, but several characters in on the 300's a "G" was 2WD and an "H" was 4WD. It's likely the same for all Lexus models.

    Also, if you can look under the rear, the absence of a driveshaft and rear differential is a pretty good indicator it's 2WD ;) . If there's a driveshaft down the middle leading to a rear differential that distributes power via shafts with black boots to the rear wheels, that's your 4WD.
  • ndeborahkndeborahk Member Posts: 18
    I am thinking about buying a 2008 RX 350 and was wondering if there are any major issues with the car? Consumer reports seems to like it. I have a 2004 Toyota Sienna Limited that has been a disaster and want to try to avoid getting into the same situation again.

    Thanks for any advice and guidance you can give me.
  • fry2fry2 Member Posts: 3
    RX350, 2008 is generally good. I havn't epxperienced big issues until now. However, don't expect it is "perfect". You may unluckily find rattling sound on the sun roof (can be fixed under warranty), louder gear shift than you may expect for such a high profile SUV. Try to bring a mechanic to test drive and try the one made in Japan with a VIN sarting with J. Good luck.
  • maximafanmaximafan Member Posts: 592
    I've had my 2007 RX350 for over three years now, and it's a very
    nice car. I've had no problems, except for a few interior rattle issues.
    That being said, I've had an opportunity to drive the 2009 RX350,
    not the 2010, as a loaner vehicle when I take my RX in for the oil change, tire rotation(this last service trip also involved putting new
    front brake pads) This may be a subtle difference, but I like the
    way the 2009 RX's drive! They seem to drive or handle a little tighter and the steering seems a little less boosted than on my 2007. Also, the suspension when going over bumps and imperfections on the road seems to soak those up a little better, but that could be just that my car is more than three years old now and the suspension feel would end up being a little different from a car that just came out last year.

    My lease is up next year, and I kind of wish I could find a used
    2009 RX. But it's got to be in Matador Red! ;) Love, love that color!
    I've seen a couple of them in the service area of my Lexus dealer,
    and, gosh, are they beautiful!! Lexus didn't offer this color on my
    model year RX. I understand a 2009 would be higher in price right now, but if you could try test driving one, hopefully you'll notice what I experienced. Good Luck!
  • ndeborahkndeborahk Member Posts: 18
    Thanks so much for the information! I really appreciate it
  • wwestwwest Member Posts: 10,706
    If you have experienced the 1-2 second "re-acceleration" delay/hesitation the RX will have the same "feature".
  • jacks2jacks2 Member Posts: 45
    I noticed a occasional quick single flash of the EPS warning light at slow speed or starting from a stop, it's intermittent and can't duplicate it at will. Has anyone else experience this and will an intermittent waring flash record somewhere where it can verified by a service department. I have 1K miles on the vehicle and happened about 3x that I'm aware of.

    Thanks

    jack2
  • wwestwwest Member Posts: 10,706
    The Toyota/Lexus EPS is marginally powered for use at low speeds insofar as quick stearing reaction/following to your quicker movements of the stearing wheel are concerned. It even has a "fault" mode wherein it runs in derated mode if/when to much use of it is made and it begins to overheat.

    The other possibility is that the thermistor used to detect the EPS' electronic drive module's overheat condition is marginal or has an intermittent connection.
  • meditchmeditch Member Posts: 6
    I have posted previous messages re. front bumper Service Bulletins, etc., (now corrected ); poor location of 12V outlet in arm rest and lack of bumper strips on side doors.

    Yesterday, driving for first time in a rainstorm, parked and opened drivers door and was drenched. There is no Drip Drain and rainwater drops straight down as you exit. Not a pleasant experience! All this I am sure to enable designers to achieve a "clean line." Whatever happened to practical?

    The Pickle King
  • wwestwwest Member Posts: 10,706
    The "Drip Drain" is now a part of the door weather stripping/seal/insulation, but easily overcome.
  • behzad1behzad1 Member Posts: 5
    Hello Jack,

    I have bought a RX350 2010 last week and on my first mountain road trip I had the same experience with the message on my display showing Power Steering problem.
    The problem is my power steering stopped working and I have to stop the car and turn the engine off and on to get back my power steering working. It happened 3 times and in all cases my speed was very slow. However it could be a disaster if it stops working at high speed mountain roads. I checked the user manual and it says it is because of EPS malfunction. Have you been able to solve your problem?
    Dose any one has a clue on this failure. I would appreciate your comment.

    Cheers,
    Behzad
  • wwestwwest Member Posts: 10,706
    These new EPS, Electric Power Stearing, systems are quite seriously UNDERPOWERED insofar as continuous, constant duty, (lots of stearing corrective inputs in a relatively short period) is concerned. In that situation the electronics control module's power transistors will often overheat.

    But I have understood that the above is explained in the owners manual.
  • jacks2jacks2 Member Posts: 45
    Behzad

    Unfortunately the service department was unable to reproduce the problem during a "lengthy and comprehensive test drive". Ironically my odometer logged only 1 mile which says a lot for their lengthy test drive or credibility.

    So far I find my Lexus post purchase experience disappointing. What is the time element for one to receive a factory survey?
  • behzad1behzad1 Member Posts: 5
    Hi Jack,
    I live in Iran and I don't think that the factory will send me a survey at all. These cars are designed for Middle East Arabic countries like UAE and Saudi Arabia and are imported to Iran by individuals. However, I send the car to the local dealer of Toyota and they could not diagnose the problem so far.
    As far as I think you have better access to services and supports over there, I really appreciate if you keep me posted on any progress to solve this problem.
    Behzad
  • behzad1behzad1 Member Posts: 5
    dear Willard,
    Thank you for your comment on my post. You have mentioned, EPS is powered for use at low speeds. Dose that mean, this problem will not occur at high speeds?
    To be honest, I don't dare to drive my lexus anymore.
    Behzad
  • wwestwwest Member Posts: 10,706
    Think about how much use the EPS would be put to if you parallel parked on a gravel roadbed 10 times in short succession.

    As may already know less power stearing effort is required the higher you speed is.

    I wouldn't go so far as to advise you not to drive your Lexus, just be fully aware of the EPS limitations. And in the past I thought the EPS would first drop into a low assistance mode when it began to overheat with a warning to the driver and then only shut down completely if the warning wasn't "heeded".
  • behzad1behzad1 Member Posts: 5
    Thank you for the information. Now I have a better understanding of EPS system. However, most of the time I received this message I was driving at a law speed between 20-30 km/hr at a normal driving condition without any harsh use of EPS.
    And I lost my steering power almost at the same time I received the warning message.
  • wwestwwest Member Posts: 10,706
    Roadbed ruts, frozen snow/slush...??
  • behzad1behzad1 Member Posts: 5
    yeah, there were roadbed ruts first time it happened to me. However, It is getting worse, I receive this message two to three times in a short drive from my office to home. There are some speed bumps on my way home. could that be the reason??
  • wwestwwest Member Posts: 10,706
    Either your EPS is defective or for some reason it is having to work harder on a regular, consistent, basis than the designers expected. Road rutting would undoubtedly be a contributing factor that first time.

    Upgraded to wider tire tread with more CSA, stearing force shock absorber added, lack of adequate cooling for the control module..??

    Maybe even a failing CV joint.

    I have even heard of the torque tube, stearing force sensor, being twisted, taking a permanent twist, due to extraordinary driver stearing input forces being used at some time in the past. The effect from this latter often results in the EPS partially fighting the driver's stearing wheel input, even to the point of opposite forces to the input.
  • jdw48jdw48 Member Posts: 4
    I have a 07 350 I just purchased, and have a rattling noise in the left side sunroof area, do you know what they did to fix it. it's out of warranty (miles)
  • asmirnoffasmirnoff Member Posts: 2
    I got the same problem on my RX350, rattling noise on coming from the left side of the sunroof. Anybody ????? its driving me nuts.
  • jdw48jdw48 Member Posts: 4
    Has anyone figured out how to fix this Rattle problem, i have taken this car apart trying to find it. HELP
  • jacks2jacks2 Member Posts: 45
    edited December 2010
    Drove 40+ miles through heavy snow this week keeping speed at or below 20 mph without any noticeable slippage or loss of control.

    Initially ETC Snow control and AWD lock mode failed to engage nonetheless I was able to drive through an un-plowed area in bumper high snow without the benefit of those features.

    I felt my 2010 AWD RX ( 19" Bridgestone MS tires) handled as well or better than my 2007 AWD RX did.

    A visible AWD medallion would be helpful when passing a chain control checkpoint.

    Jack
  • wwestwwest Member Posts: 10,706
    Your post reads as if you have the earlier RX350 F/awd system WITHOUT the ability to manually "lock" the rear drive in at low speeds.

    In any case I would NEVER drive any F/awd system, and most certainly NOT the early RX350 version, without at least the rear tire chains when the "chains required" sign is up.

    But then it's your life at risk, not "mine", mostly.
  • wwestwwest Member Posts: 10,706
    "..ETC Snow control and AWD lock mode failed to engage.."

    What were your indications of this, how did you know...?

    To my knowledge ETC only modifies the shift pattern and the DBW gas pedal response rate/"gain". I also understand that the manual F/AWD lock mode only works at lower speeds, below 20(?) mph.
  • wwestwwest Member Posts: 10,706
    Has it occurred to you, or any RX owner for that matter, that Lexus does not label the RX as "AWD" since there might be some serious liability in FALSELY making that claim..??

    The RX series has not been even a "true" F/awd system since the beginning of the '01 model year. The revision in 2010 represents a VAST improvement but still NO CIGAR.

    No RX should be trusted to perform dynamically, on an adverse condition roadbed, as would an actual F/awd or even a R/awd system, let alone a TRULY capable RWD/4WD vehicle.
  • jacks2jacks2 Member Posts: 45
    When first starting and attempting to engage ETC and lock mode no indication appeared on the instrument panel. After several minutes of driving control switches worked and displayed on the panel.

    "Lock mode" did cut off above 20 mph, my 2007 AWD did not have a lock mode.

    Do you have an RX or have you personally operated one under adverse driving conditions?

    This is my second RX, other than crappy paint that chips much too easily I like this vehicle.

    Thanks for responding to my post, have a happy new year.

    Jack
  • jacks2jacks2 Member Posts: 45

    "I would NEVER drive any F/awd system, and most certainly NOT the early RX350 version, without at least the rear tire chains when the "chains required" sign is up. "


    Why the rear? The manual recommends chains on the front wheels.
  • wwestwwest Member Posts: 10,706
    "lock mode" is only available with the newer F/awd system, the one that has an electromechanical clutch housed in the front of the rear diff'l. The lock mode indicator may not go off but the actual rear drive engagement goes off at higher speeds.

    My first RX purchase was a 2000 and then the next year I traded "up" (or so I thought at the time) to get the TC, VSC, and HID headlight options. The '00 had a more functional F/awd system but as it happened that was at least partially the reason for all the premature transaxle failures for the 99-00 RX300.

    So as of 2001 the rear LSD option was dropped and the VC fluid formulation was changed to forever remain "flaccid". The VC was really of no matter anyway since TC activation will never allow it to come into "play". That basically why the VC was dropped entirely during teh RX330 model run. The RX300, 330 and early 350's or basically ONE-WHEEL drive vehicles, 3 simple "open" diff'ls, front, center, and rear. TC, Traction Control, is used to "simulate" F/awd functionality but only reactively, AFTER wheelspin/slip is detected.

    My '01 F/awd RX300, now at ~80,000 miles (2 ATF drain/refills) has survived no less than 10 winters, wintertime trips to MT, Ski trips, etc. We have about 3 inches of hard frozen, crusty, snow and ice on the ground here at this very moment.
  • wwestwwest Member Posts: 10,706
    Your manual also States that higher traction at the front vs the rear is to be avoided as that configuation has a HIGH potential for loss of direction control. I. E. new tires should ONLY go on the rear if only buying two.

    Prior to ABS tire chains ONLY on the front of a FWD or F/awd vehicle was extremely hazardous. Hard braking on a slippery surface, especially downhill, and the front would "anchor" oftentimes with the result of the rear of the car taking the lead, jack-knifing, if you will.

    Obiviously ABS serves to abate that problem to a great extent But then we have the issue of inadvertent engine compression braking sometimes resulting in the same outcome. Many newer vehicles have a new feature, "inverse" ABS, automatically up-rev the engine if/when there is an indication that engine compression braking has/is resulting in front wheelslip/skid.

    So, I use "drag" chains first and then add the front tire chains only when more "drive" traction is required.

    Oh, you will need to add wheel spacers at the rear in order to use rear tire chains since otherwise the clearance between the suspension and tire tread is to tire.

    I have 1.5" wheel spacers all around and upgrated to 17X8 wheels and +1 tires. Wider stance against rollover, more tread on the ground, less suspension softness.
  • jdw48jdw48 Member Posts: 4
    i just got my 07 RX350 back from an independent shop. the Rattle came from the plastic covers on the forward rails. Also when you open up your sunroof on each side their is a black plastic rail for cosmetics only, but that could rattle. Also on the gas tank their is a shield that could rattle as well, just cut the shield back about 3 inches.
    i hope one of these will fix your problems.
    Don
  • ca2nyca2ny Member Posts: 3
  • jacks2jacks2 Member Posts: 45
  • jacks2jacks2 Member Posts: 45
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