Last post on Aug 16, 2011 at 5:24 PM
You are in the Toyota Highlander
What is this discussion about?
Toyota Highlander, Car Buying, SUV
#72 of 172 Re: Just bought a NEW 2010 Highlander Limited [wwest]
Dec 29, 2009 (9:04 am)
Could you go into more detail, or at least throw some marketing names around so I can go look into it myself?
Or is the problem that Toyota itself not clear what is on the HL?
Does this 'one-wheel-drive' (I take it that's your tongue-in-cheek wording) mean that if the vehicle has ice under three wheels, its not going anywhere, or, it will move once the traction control starts grabbing the disk brakes on the spinning tires?
I have a 2002 Subaru Forester 'S' automatic with viscous fluid limited slip rear differential, I was looking to get more space for the family. Not sure about current Subies, but with the automatic 2002, most of the power is going to the front wheels, and when they slip in the snow I hear a clunk and then the car takes off. Never been stuck on the street. I never got around to figuring out what gives between the two front wheels on this car, or if the present Subies are better.
#73 of 172 Re: Just bought a NEW 2010 Highlander Limited [illinoiscentra]
Dec 29, 2009 (10:20 am)
First, think of the old RWD cars with a simple "open" type differential, one of the two rear wheels slip, the diff'l does "its' job", evenly distributing torque, engine torque now LIMITED by the low traction coefficient of the slipping wheel, and you just sit there, STUCK, with that one wheel spinning uselessly.
Now add two more of those simple open diff'ls, one in front and one in center.
Same as with the OLD RWD, one-wheel slip/spins, thereby limiting engine torque, severely so, the other wheels remaining with traction get an equal level of engine torque, but....
TC, Traction Control, is used to hopefully alleviate the above circumstance. The activation of TC will be INSTANTANEOUS and COMPLETE upon detection of wheelspin, applying braking to the slipping wheel(s) and dethrottling the engine down to idle or closely nearby. Absent the dethrottling there might be a threat of rotor overheating and later warpage.
And remember that this is a "base" FWD vehicle and therefore it is more likely than otherwise that it will be a front driven wheel that first slips/spins. Loss of traction on the front wheels is considered a really serious matter so TC activation MUST be INSTANT and COMPLETE otherwise the threat of loss of directional control would be highly probable.
You can think of the new Venza F/awd system as a programmable VC. Anytime there is a threat of loss of traction, mostly during acceleration, even acceleration while turning, the "VC" will be tightened up in order to distribute some of the high torque of/for acceleration to the rear. It is my understanding that the harder you accelerate, at least at lower speeds, the tighter the rear coupling is adjusted.
But again, since this is, remains, and always will be a base FWD vehicle the threat of loss of directional control due to front driven wheel slip/spin must be considered to be potentially so very HAZARDOUS that TC activation will remain INSTANT and COMPLETE even though the rear drive will also be coupled in at the same time.
Hopefully once the HL is adapted for this new system a manual engagement switch will be provided.
But I wouldn't place any bets on that.
#74 of 172 Re: Just bought a NEW 2010 Highlander Limited [illinoiscentra]
Dec 29, 2009 (10:27 am)
"..Toyota itself not clear.."
Toyota makes it quite clear as to when their F/awd system works.
"..ice under three wheels.."
No only one wheel need be "tractionless" and the HL will/can/might be STUCK. In some instances the activation of TC will get you moving but there have been enough cases otherwise, and the appropriate public outcry, that the current HL system has a TC disable capability.
#75 of 172 Re: Just bought a NEW 2010 Highlander Limited [wwest]
Dec 29, 2009 (2:14 pm)
... but there have been enough cases otherwise ...
Is/was this with a FWD or with AWD? Cuz I have a bad feeling you are telling me its with the AWD too. In other words, what I have right now I will loose if I trade in the Forester on a HL.
.... current HL system has a TC disable capability ...
Must have missed that on the test drive, where is it (if you don't mind)?
#76 of 172 Re: Just bought a NEW 2010 Highlander Limited [illinoiscentra]
Dec 29, 2009 (4:56 pm)
TC is pretty agressive, for good, stated, reason, on both the FWD and F/awd versions of the HL. Even with my '01 F/awd RX300, supposedly with a VC to enage rear drive with front wheelspin/slip, TC will INSTANTLY activate, braking and dethrottling via EFI fuel starvation.
Since TC prevents any and all VC capability the TC fluid formulation for my '01 was changed so the VC remains forever flaccid. The VC was eliminated entirely for the RX330 model run and more likely than otherwise the RX350.
The latest model RWD I have driven with TC was a 2000 GS300. With the GS TC was just as agressive insofar as braking the rear drive wheels but has a significant delay in dethrottling the engine. Loss of traction due to wheelspin/slip is not nearly as potentially hazardous as with FWD and F/awd vehicle as the driver remain with FULL direction control. That braking delay also gives the driver a chance to react and "feather" the throttle.
Don't know the location without referring to techinfo.toyota.com but I'm sure the saleperson will advise if asked. The PB, Push-Button is first used to disable TC and then once TC has been disabled a second push will disable VSC.
The 2011 Sienna, coming in February, will have the new Venza F/awd system. The 2010 RX350 already has the new Venza system AND has a switch to engage the rear drive manually.
So far only the Venza is available with the new I4 engine and the new F/awd system. I'm hoping the Sienna will be made available with the I4 and the new F/awd system once the I4 is upgraded to DFI...and maybe Toyota's new e/VVT-i (EXTENDED/VVT-i) system.
The e/VVT-i system is being used in the current HSD (Hybrid Synergy Drive) vehicles to change the engine from Otto mode to the Atkinson cycle mode. HIGH compression mode for light to moderate engine loading (partial cylinder filling), then a lower CR for high engine loading, WOT.
With DFI and e/VVT-i the CR could be 15-16:1 in Otto mode, and lowered to the DFI "standard" of 12:1 with WOT.
#77 of 172 Re: Just bought a NEW 2010 Highlander Limited [wwest]
Dec 30, 2009 (8:58 am)
The Forester is the second car, the 'family' car is a 2009 FWD Sienna LE - I just did not like the idea of run flat tires on the AWD- read from various sites of people complaining about they are only good for x miles, and x is less than the distance from Lake Geneva, Wisconsin to our house, a trip likely to be made on a Sunday night -- that is, a night no one around to fix a run-flat (if they even know how), or a sell a whole tire. I chose the lesser of two evils. Garage has a low door, so the motorized lift gate of an XLE might hit it, and I didn't like the center console on the XLE either, can't get up and smack the kids like in the LE or the 2000 Sienna we had.
Gotcha on the Venza, I am considering that car too. Full size spare. Have other issues with it.
#78 of 172 Re: Just bought a NEW 2010 Highlander Limited [illinoiscentra]
Dec 30, 2009 (9:09 am)
If the new 2011 Sienna was available with F/awd AND the I4 then RFT's would not prevent me from buying. With the I4 upgraded to DFI then I would be waiting at the dealer's door to place an order this morning.
Even if you immediately replaced the RFT's with something more acceptable what would be the cost vs risking a base FWD..??
I just put 4 good tires, quiet and comfortably riding, on a '95 LS400 for under $400.
Dec 31, 2009 (8:33 am)
I only researched the 2009 Sienna, I have no clue about 2010 or 2011. The key problem with the 2009 AWD Sienna is that even if you replace the the run flat tires with conventional tires, where do you put the spare? So that the third row seats could fold down into the pocket behind the rear axle, the spare tire is hung between the wheels. Somehow the spare at that location and AWD would not work together. Remember this is the 2009, no clue about 2011.
I don't know if I would want a mini-van with a four cylinder engine. Unless I was given it free I suppose.
Duty calls, I'll check back here tomorrow.
#80 of 172 Re: RFT [illinoiscentra]
Dec 31, 2009 (9:30 am)
Given the level of non-occurance of flat tires over the past 20-30 years I'm not sure I would worry about having a spare. But if I did one of those "swing-a-way" rear tire carryers....
The Venza I4 has 187HP, roughly equal to the 190HP the V6 produced for my HEAVY '92 Jeep Cherokee Limited. With DFI it would probably reach 200HP easily. And with e/VVT-i another 5MPG hwy.
#81 of 172 Do not buy Toyota Highlander!!!!!!!!!!!!!!!
Jan 08, 2010 (6:42 pm)
If you plan to use the Toyota Highlander to go to work and you are driving in the city like Philadelphia, take my advise and don't buy this SUV. Last month, I bought a AWD, V6 Toyota Highlander 2010 with 7 miles on it. Now I regret it so much. I can only get 13 to 14 miles per gallon on this SUV. One full tank of gas got me less than 250 miles! This SUV is a gas guzzler!!! I bought it thinking at will get about 17 or 18 miles like they said, but it was a total rip off! Anyone thinking about buying it need to think twice or more before getting it. The interior is not that great either. Thing got stuck easily on the black cloth on the door. If I can undo it, I would return my SUV right now!