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Comments
With an open center differential the "problem" occurs when traction is significantly lower at one end or the other to the point of breakaway, wheel slippage. In that case ALL of the effort will be expended at the end with least traction.
This is where the HL or RX VC, viscous coupling, clutch, mounted across the two outputs of the center differential, is supposed to step in and overcome this shortcoming of the open differential.
The basic principle of the VC is that as the two sets of interspersed clutch plates rotate at disparate rates the viscous fluid into which they are immersed will become heated and increase its viscosity dramatically. The increase in viscosity increases the coupling coefficient between the two sets of clutch plates forcing "equal" drive torque to the non-slipping end.
The open center differentail is placed there to begin with because there are times when the front and rear wheels MUST be allowed to turn at different rates. All VCs are designed for some level of onset coupling lag, typically hundreds of milliseconds, for this very same reason.
But in the case of the HL and RX the real problem is lack of complexity, the simplicity, of the VC design.
If the HL and RX VCs were designed to "stiffen" to the point of actual 50/50 coupling and just about then you happened to need to step on your brakes in panic mode that would likely result in loss of control of the vehicle in many circumstances.
Your front brakes will ALWAYS do about 80% of the work of stopping the vehicle when braking severely. What this means to you is that they will rotate a lot more slowly (ABS, remember?) that the rear during such severe braking.
Now, if the front driveline were HARD coupled to the rear driveline (VC with HIGH coupling coefficient) at this particular time then the severe, hard, braking of the front wheels would control the rotational rate of the rear wheels, very likely locking them and causing you to lose directional control.
So Toyota/Lexus chose the KISS route. Their VC is designed such that the F/R coupling is NEVER more than 25%, and this only under extreme conditions over an extended period of tens of seconds.
So, unlike the Chrysler T&C AWD minivan series, they don't need an over-running clutch in the rear driveline for uncoupling the rear from the from during severe braking.
That's why, on adverse roadbed conditions, the T&C AWD/VC system will outperform the HL or RX, head and shoulders.
Let alone the fact that you can safely use snowchains on the T&C if the going gets really rough.
But even though it "works", it's still typically not worth the money.
If you happen to have a three position memory seat, mirror, etc, use the third position to tilt the mirrors down about 5 degrees at night. Works much better.
Before you have yours installed you might want to check about how well it will work with rear privacy glass.
Nimrod99: Polite suggestion acknowledged but will be ignored, politely. Just because I went out and bought the HL owners manual and shop manuals doesn't mean I'll go out and purchase an actual HL in order to participate.
highinkc: In some parts of the world the A/C can be used year-round to dehumidify the cabin's incoming airflow and thereby help to defog the windshield. The ability of the A/C to accomplish this task with any level of efficiency declines precipitously as the ambient temperature declines below 50 to 55 degree F until at about 35F it is non-existant.
The idiot designers at NipponDenso, Denso USA, also forgot that once the Defrost/defog/demist function is turned off, and the A/C is subsequently turned off, any moisture just previously condensed onto the A/C evaporator vanes will begin to evaporator into the cabin airstream.
Meaning that once you have used the A/C for defog assist you will soon need to use it again and again and ......
Personally I disable the A/C entirely by unplugging the connector at the refrigerant pressure switch/sensor just in front of the condensor/radiator assembly in the fall and don't plug it in again until I discover I need A/C the next year.
The best, most sure way to defog your windshield and keep it defogged in cold weather is to apply heated airflow. Turn up the heat and blower level when, just before, you activate the defog function.
In order to achieve higher MPG ratings AND use the A/C year 'round Toyota/Lexus severely restricts the outflow of cabin air.
I have had instances wherein with four people in an LS400 in the wintertime with the OAT so low the A/C was automatically locked out the interior humidity become so high my only recourse was to lower the rear windows slightly. This in the dead of winter on a snowy high mountain pass.
LS400: absolute best car/value in the world and can't defog its own windshield.
And yes, I'm well aware that the HL doesn't have memory seats, but some of us, maybe many of us, own more than one car/vehicle. So it was only an OT helpful hint.
I checked with most of the dealers in the immediate Boston area that are near me (Woburn, IRA, Lexington, Watertown, Boch). I found one that would sell for $300 over invoice; a couple for $500 over and others for more. Let me know if you want any specifics.
Another NH dealer that offers near invoice is Autofair in Manchester. They have a nice website that provides their bottom line price, which is slightly above invoice. Their no-haggle pricing is better than any of the pricing I got after haggling with the Boston area dealers.
What dealers are you dealing with and what kind of pricing are they giving you ?
But I do agree with You. While I value the auto-dimming feature of little use, I find having constant or ready access to the OAT of utmost importance in the wintertime. I never use cruise control with the OAT below 40F. Not to denigrate your need or use of the compass feature in any way, but the only need I have ever found for a compass "on the ground" is while hiking out in the Northwest woods in an overcast.
But to ease your mind even further, maybe, I just recently purchased an aftermarket mirror just as you describe, but primarily for the OAT feature.
We suggest that you not provide detailed contact information as it conflicts with the solicitation and promotion section of our Terms of Use. Naming a dealership is fine or even a web address but providing the name and phone number of a specific salesperson crosses the line.
tidester, host
The rear speakers are coaxial, meaning that they contain both a woofer and a tweeter.
For the eight speaker sound system there is indeed a separate amplifier apart from the head unit.
At first you said: "[auto dimming] Actually works unless you darken the rear glass."
Now you say: "that adding privacy glass, or film, to the rear would reduce the effectiveness of the functionality of the auto-dimming feature since the rear looking photocell would be "filtered""
So, you now admit that auto dimming mirrors can work but with reduced effectiveness. You say this as if the designers were unaware of the existence of privacy glass and I would still be curious to know how you came to such a conclusion. Beyond that, I do appreciate the retraction.
You then stated: "But even though it "works", it's still typically not worth the money." and "So my response that it isn't worth the money was appropriate"
This was followed by: "No, I only have a firm grip on my own values" I'm sorry, where in those previous quotes did you indicate anything beyond a flat statement of fact, rather than opinion?
Finally, I have to ask you about one last quote: "Not to denigrate your need or use of the compass feature in any way, but the only need I have ever found for a compass "on the ground" is while hiking out in the Northwest woods in an overcast." Why would you even say that? What is the point of this statement? You have no idea how I use my vehicle, where I use it or anything else so why even bring up the fact that you don't have a use for a compass in a vehicle? It seems a rather pointless statement... oh yeah, its you so I guess I should be used to pointless statements shouldn't I?
This is all in the face of pretty much every other owner of these vehicles who see and feel very different results. We have about 4" in snow here in Buffalo today and, again, closely watching the wheels of many of the AWD Highlanders here in stock, when they spin their tires, there is one front and one rear tire that spin if they do spin the wheels before getting traction.
NONE of wwest's comments are supported by real-world experience from other owners or by people with any technical expertise on the systems used in these vehicles.
Just a notice to take comments with a grain of salt.
Ken
cliffy1: Why would you even say that? What is the point of this statement?
I believe it's called discussion. What exactly is wrong with wwest commenting that he doesn't have a need for a compass. Methinks you were taking personal offense where none was intended or even expressed.
toyotaken: Just a notice to take [wwest's] comments with a grain of salt.
One might apply that advice to all posts.
The topic here is not wwest or any other individual. The topic is the Higlander. Let's stick to it!
tidester, host
Based upon my needs and my reasoning for purchasing this SUV, I am quite satisfied with its performance so far. Are there some minor questions or annoyances? Sure, but again, they are minor and aside from pointing them out to other potential owners, there is little I can do about them.
As far as this site, I enjoy the information being shared, but I think it's time to get back on point and put the personal stuff behind us. No offense - just my opinion.
Due to questioning on forum validated my findings on an actual 4 wheel dynomometer.
Now if someone wants to really argue that the HL is different than the 01 AWD RX I tested then I will not dispute that except to say that the two sets of shop manuals are exactly the same in these areas.
Now as you know, I own an 01 AWD RX, traded up from an 00 AWD RX to get HID and VSC. I will likely trade up again if the 330 is "attractive" enough. I don't have a real problem with these limitations as long as I know of them and thereby do not allow them to get me into trouble, no trips over donner pass in the wintertime.
Knowledge IS POWER.
Sorry about my earlier post, but while Knowledge is power, a little knowledge taken out of context and without "the whole picture" is dangerous.
Ken
Thanks for the clarification on what dealer/salesperson info is ok to post. I didn't want to cross that line.
-stuartc
Auto Dimming mirror
Works great even though my rear windows are dark (privacy tint).
I like the feature very much - especially when people in Excursions or other big trucks are behind me.
Chains
You shouldn't put chains on the rear anyway. Chains should go on the front wheels (AWD vehicle). Reason - you need to be able to steer and brake and chains on the front allow that.
VC works when the fluid heats up? The HL tranny drives both front and rear drive trains all the time - it doesn't magically happen when the fluid heats up? In reality - viscocity decreases with temperature.
I just signed papers for the purchase of a Bluestone Limited that I was able to buy at invoice. I felt that the safety aspect of the VSC option was worth the extra money. Additionally, I felt my wife, who will be the principal driver, deserves the extras that the Limited offers. I really feel good about this purchase.
The Auto-Dimming mirror was one of the options that was included with this Highlander, so I'm getting it whether I wanted it or not. This option still feels like a gimmick to me, but since I've never experienced this type of mirror, I'll reserve judgement on it.
IMMHO AWD is of most value to john q public when just starting out in motion. Once you're moving momentum/inertia often takes the place of good traction, unless what you're trying to do is STOP that is.
As I said earlier a pure open diff'l, ONLY, allows any level of disparate rotational rates between its two output shafts, used in center, front, rear, whatever.
Almost ALL VCs are designed to have significant LAG time before firming up and increasing the coupling coefficient between the two diff'l output shafts. Oftentimes this delay is accomplished by adding a gas/air bubble within the hermetically sealed VC case.
Viscosity vs temperature. Basically you are correct, viscosity of any liquid does ALWAYS decrease with rising temperatures. VCs actually work by increasing the EFFECTIVE viscosity as temperature rises.
HOW? BLACK MAGIC!
The formulation of the silicon based viscous fluid is such that viscosity itself remains relatively flat over a wide range of temperatures. What does happen as the fluid's temperature rises with disparate rotational rates of the VC clutch plates is that the viscous fluid EXPANDS.
Remember that gas/air bubble? As the viscous fluid expands the bubble of air is compressed until it resembles a small black hole. Only after the bubble is "fully" compressed to black hole size by the rising fluid pressure will the increasing fluid pressure begin to increase the coupling coefficient of the two sets of VC clutch plates.
Want to test all of this by yourself?
Get into any vehicle that can actually LOCK the center diff'l and drive it in a tight circle,very slowly, on dry pavement. Be sure and keep your thumbs and fingers outside of the steering wheel rim. What you're going to feel is the kickback in the steering wheel due to driveline windup from the front and rear drivelines being forced, by the locked center diff'l, to turn at equal rates.
Now get into any vehicle that truly has AWD of the VC type and do the same thing. My (perfect) example would be any AWD Chrysler minivan. It might take more than one complete circle before that gas bubble is completely compressed but then you should start to feel the same steering wheel "kickback" effect as you felt with the fully locked center diff'l.
Now try the same test in ANY HL or RX.
Be aware that some Jeeps have U-joints at the front and if so this will exacerbate the kickback effect with the center diff'l locked. And DO NOT perform this locked center diff'l test for an extended period nor under hard acceleration, you can easily damage the driveline that way, permanently.
20MPH speed. Toyotaken: You're perfectly correct of course. It's the time period of/for which the two drivelines have disparate rotational rates that's important, not the actual speed at which this occurs. And it is very true that the lower the speed the longer it will take to heat the VC fluid to the point of increasing the coupling.
I stated the 20MPH only as a circumstance/parameter of my testing. The important point is that I had the rear wheel fully stopped using the torque wrench (forgot to mention that the opposite rear wheel was blocked from turning by a 2X2) for many seconds.
And please, NO ONE should try this test of/by themselves. I did lots of preliminary testing to assure myself that I could use the torque wrench in this manner safely.
Snowchains only on the front. If you care to peruse your HL or RX owners manual you will find a section on the use of tires with winter treads. Your owners manual advises that you should NEVER run the vehicle with winter treads on the front and not the rear. I think it says something to the effect of "loss of control of the vehicle can result from this".
What "this" actually is is greater traction on the front than on the rear, a really, REALLY, easy way to get yourself quickly buried in a snowbank, or worse.
The only complaint is with the speakers. They certainly do not measure-up to the quality reputation that Toyota has built.
I installed Polk GHX365 speakers with no additional modifications to the system. What a difference... it sounds great! The four speakers cost $150.
In response to some questions about cargo and floor mats... I went to a home center and purchased a 4'x 6' rubber carpet mat and cut the mat to fit the cargo area. The gray color matches the interior, looks very nice and cost only $15. I also purchased a piece of carpet runner for $8 and cut it to fit the rear floor area. I then bought front & rear rubber mats for under $30 at a club store. The result is a complete set of mats that provide plenty of protection, look good, and cost little.
If you buy the "Mito" auto dimming mirror - you can get compass and outside temp on the same mirror. It should come with the outside temperature probe which you will have to install.
http://www.mitocorp.com/nvsmirro.htm
http://www.mitocorp.com/mirror_installation.htm
I would love to see a link to a site that confirms your hypothesis.
thanks
I also like to read my compass situated on the mirror.
Had my Ltd '02 since Feb. '02 and am very pleased with it.
And if it helps with the driveway scenario as well, well then that is probably more than the Toyota literature ever claimed it would do, so then that is a plus.
Toyota offers several trucks in its line-up with a more heavy-duty 4WD system than this one, and if that is what you need, then that is what you should buy.
2014 Mini Cooper (stick shift of course), 2016 Camry hybrid, 2009 Outback Sport 5-spd (keeping the stick alive)
Also the Toyota dealers acted like they were doing me a favor by selling me a piece of crap overpriced Highlander. The Pilot has more room, a bigger engine, netter transmission, and better resale value. The Honda dealers were more receptive and acted like they were friends for life.
Toyota can SUCK IT!!!!!!!!!!!!!!
tidester, host
Good and bad dealers are everywhere, HL's size makes it easier to park in the city, and for comparably equipped vehicles, it seems real-world prices on HLs are a lot less than Pilots.
Hey look, I only wrote that once! :-)
2014 Mini Cooper (stick shift of course), 2016 Camry hybrid, 2009 Outback Sport 5-spd (keeping the stick alive)
Don't forget the Nissan Pathfinder vs Toyota 4Runner vs Dodge Durango vs Honda Pilot vs Toyota Highlander - please advise! discussion for this type of comparision.
Steve, Host
Hopefully the HL will get the same upgrade which will likely mean VSC/Trac will become standard.
No longer any reason to settle for FWD!
And as far as sludge, did you stop to consider the Honda transmission recall that affected more than 15 times as many Hondas as the sludge thing? LOL IIRC, that recall included the MDX, which uses an almost identical powertrain, and the same transmission.
I won't even touch the gender security thing....
On a serious note, I am very curious to know if you priced out a comparably equipped HL, or if you stopped when you were treated rudely by the dealer...I would be very surprised if a comparably equipped HL could not be had for less than the Pilot.
2014 Mini Cooper (stick shift of course), 2016 Camry hybrid, 2009 Outback Sport 5-spd (keeping the stick alive)
HL is outselling Pilot even though Pilot is the brand new model! Just thought I would mention that...in the midsize segment there is an awful lot of competition...
2014 Mini Cooper (stick shift of course), 2016 Camry hybrid, 2009 Outback Sport 5-spd (keeping the stick alive)
I looked into the Pilot before deciding on my V6 AWD ltd HL.
If you go to the nhtsa.gov site and look at the service bulletins on the 2003 Pilot - you will see quite a lot listed, There are zero for the 2003 Highlander.
My reasons for NOT getting a Pilot
1) Red rear turn signals (Inherently unsafe compared to amber rear turn signals)
2) Too wide (77" is way to wide to park without getting door dings)
3) 3 rows of seats (I only need 1 row - maybe the second row gets used 1 day per year?)
4) Too heavy (240 hp for 4,440 lbs = 18.5 lbs/Hp
Highlander is 220 hp for 3880 lbs = 17.6 lbs/hp)
5) No traction control (VSC)
6) No moon roof
7) No heated side mirrors (for cold weather)
As for the sludge issue - its just lazy owners who don't change their old according to the maintenance interval. Granted - the engine may be susceptable to sludging only if you don't change the oil.
tidester, host
I would like you to know that NASA continues to communicate with Pioneer 10, now almost 8 BILLION miles from earth, compliments of this "home engineer".
cliffy1:
How is it that you can denigrate, disparage, and question the information I post, and " beat up on willard" if you ignore my posts by simply paging down?
Telepathic communications?
As for belittling other people, that will do nothing to strengthen your argument or increase the respect others in the forum might have for you. It's OK to disagree, just don't become disagreeable.
would it help if I double up on my apologies?
Not paying close enough attention am I?
Guess this means you're not telepathic after all, DAMN and all those messages wasted. Oh, well, probably just as well.
the EPA mileage is 18/24 (AWD) vs the 18/22 currently for the Highlander and the 2003 RX300
When does the next design cycle start for the HL
Thanks
Ken