Last post on Aug 21, 2013 at 5:16 PM
You are in the Toyota Sequoia
What is this discussion about?
Toyota Sequoia, Toyota Highlander, Toyota 4Runner, Toyota Land Cruiser, Toyota RAV4, Toyota Tacoma, Truck, SUV
#2042 of 2493 Re: 2005 4runner SE - VSC & 4WD [2toyotas]
Feb 21, 2007 (1:34 pm)
I am traveling at the moment, HI, and for some reason I cannot access my techinfo.toyota.com account to review your owners manual.
But I wonder if you're not confusing the AWD mode of your Sequoia vs a true 4WD. Sequoia's AWD mode uses a "soft" locking of the center diff'l so all braking related functions can remain operational. In point of fact it is TC, Traction Control, that is providing this "soft" locking feature, "virtual" center and rear LSD as it were. It may even provide a low level, much lower than at the rear, of virtual LSD functionality at the front diff'l.
#2043 of 2493 Re: Shifting into and out of 4WD [wwest]
Feb 21, 2007 (1:58 pm)
Thank you for the response. I am still not clear. My car has an automatic transmission. I have two shifters. One is for shifting from drive to reverse and to neutral. The other takes me in and out of four wheel drive. I think that you are telling me that the first shifter should be in drive or reverse and that while driving dead slow I should shift the second shifter to 4WD. Am I understanding this? Thank you again.
#2044 of 2493 Re: Shifting into and out of 4WD [bakunin]
Feb 22, 2007 (12:38 am)
First, follow, try the instructions as directed in your owners manual. If that does not work then yes, drive dead slow in drive first, and then try dead slow in reverse until the 4WD clutch locks into 4WD, or unlocks, whichever may be the case.
#2045 of 2493 Locking Center Differential
Feb 28, 2007 (6:19 pm)
Couple questions as this is my first vehicle with this feature:
I understand that you should not use this feature on dry pavement however the manual suggests just avoiding dry pavement. I guess my question is if you lock the differential on dry pavement or while it is locked you hit dry pavement will you harm the system? I would seem odd to me that inadvertant dry pavement use would harm the system.
If traveling in snow or slush and you need more traction does locking the center differential provide more traction?
The manual is unclear on this too, but can you lock and unlock it while moving in H at any speed?
Thanks for the help...
#2046 of 2493 Re: Locking Center Differential [pjc1]
Feb 28, 2007 (6:28 pm)
PS I have a 2006 Land Cruiser
#2047 of 2493 Re: Locking Center Differential [pjc1]
Mar 03, 2007 (2:39 am)
Assuming it works like a 4th generation, full-time 4WD 4Runner - and I'm confident that's the case - I offer the following.
If you lock the center diff on dry pavement, you can stress the driveline, depending on how much turning you do, and possibly harm it. When my 05 4runner was new, I inadvertantly drove 30 freeway miles with the center locked and didn't realize it until I tried to exit the gas station when turning my wheels and feeling a binding. 30k miles later and TONS of hard, off-road use and apparently no damage was done. As far as stress on the system, any time the road surface is slippery to allow wheels to slip slightly and unbind the driveline, the vehicle can be driven safely in center locked mode. If you had to drive it locked on dry pavement, keeping turning to a minimum would be best.
When locked, the center diff will give better traction by defeating VSC which can cut engine power when wheels slip. So snow and ice in normal driving, you would leave the center unlocked so as to benefit from all VSC can do at speed. In unusual cirmumstances - in a ditch, a very deep snow white-out, low traction off-road, etc., locking the diff will make sure your engine power doesn't get cut by VSC but still enables traction control to limit wheel slip, side to side, on the front and back axles.
You can engage the center lock while in motion. Personally, I've never done it going more than 10mph or so but the manual seems to indicate, by omission, that there's no limit on speed.
#2048 of 2493 Re: Locking Center Differential [green]
Mar 03, 2007 (4:54 am)
Green... Thank you.
#2049 of 2493 Re: Locking Center Differential [pjc1]
Mar 05, 2007 (7:54 am)
I agree with green, in normal driving, even on snowy roads, leave the center diff unlocked. If you are going offroad, then lock the center diff.
#2050 of 2493 Found this explaination - How does Highlander 4WD work?
Mar 06, 2007 (10:13 am)
RAV4 and Highlander
These utilize a limited slip center differential and open front and rear
differentials. It is a viscous coupling center differential. If one of the
front wheels begins to spin faster than the rear, the heavy liquid in the
center begins to firm up which routes more power to the rear. Once torque is
equalized, the 50-50 power split is resumed. This system is always engaged and
requires no driver input.
It is possible to become stuck with this system. This is because of the open
front and rear differentials. If both right tires were on ice, all power would
be routed to these wheels. This is a fairly unlikely occurrence on a light duty
vehicle like these. On the Highlander, you can get VSC, which includes traction
control. If the right wheel begins to slip, brakes are applied to this wheel
and power is sent to the left. On the 4WD model, there is no rev limiter
associated with the traction control.
#2051 of 2493 Sequoia 2WD Rev Limiter
Mar 06, 2007 (12:56 pm)
So does the 2WD always engage the rev limiter which causes loss of power, and sinking in mud, sand and snow? Guess what happens next. Your stuck, and on your belly digging.
Got to be a shut off on that kind of a brainless system.