| sonko2010 |
Greetings.
How does one tell if an 2005 EX-L has AWD or is simply front wheel drive? If the vehicle I am considering does have AWD, is it on all the time or only if the front tires slip? And how does the locking rear diferential play into all of this?
Basic questions...sorry...new to the Pilot, but not to Honda.
Many thanks!
Chris |
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| mmmmark |
quote:
Originally posted by sonko2010
Greetings.
How does one tell if an 2005 EX-L has AWD or is simply front wheel drive? If the vehicle I am considering does have AWD, is it on all the time or only if the front tires slip? And how does the locking rear diferential play into all of this?
Basic questions...sorry...new to the Pilot, but not to Honda.
Many thanks!
Chris
You're in luck. This is easy. The 2wd Pilot did not debut until model year 2006.
Besides the "4wd" badge on the back of the 2006/7's, you can notice from a distance that the 4wd has two exhaust pipes extending from the muffler, while the 2wd only has one.
Someone else can probably answer better on this part, but the majority of the power is to the front wheels unless it senses slip. Do a search--there are quite a few discussions of this. |
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| sonko2010 |
Thanks, So it sounds like the 2005 has AWD. How does the VTM-4 Lock work?
Chris |
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| jestmaty |
It is mostly all automatically done for you.
If you really wish, you can press the VTM4 button on the dash and it will manually engage all four wheels (again, it will determine when/how much power to send to rear wheels). This manual operation only works in D1,D2 and R. Also, I believe it turns itself off after reaching 18mph.
Good luck. |
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| jonaz |
The VTM will not engage all four wheels at once. That would be considered a front and rear locking differential. From what Ive read, the VTM only applies power to the rear wheel, which is getting the most traction.
I live in the mountains, and Ive seen how the Pilot works in deep snow. It works pretty good, but you will never see all 4 tires spinning at once. |
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| JDKRXW |
quote:
Originally posted by jonaz --- but you will never see all 4 tires spinning at once.
Not true. If the VTM-4 button is pushed and you are in 1st or 2nd gear, the rear differential will be locked, so both rear wheel will spin (below 18mph). If both front wheels have equal traction, they will both spin in any gear at any speed.......so all 4 wheels can definitely spin at once. |
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| jonaz |
| No where in the Honda Pilot manual does it say that the Pilot has a locking rear differential. This is a big myth about our Pilots. Unless my VTM is broken, I have watched while my wife battle deep snow in our drive way, while in 1st gear with the VMT button depressed. One rear and one front tire will only spin. BTW, while rear locking differentials are somewhat common, you will hardly every see front locking differentials. The reason why, as someone explained to me, is that there is to much stress placed on the front CV joints. If you have other information, please let me know. |
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| switch |
| Auto manufacturers seem to believe that spinning two wheels, either on front or back, is dangerous. They also believe understeer is good. :mad: |
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| tfrain |
THE VTM-4 system uses a wet clutch to drive the rear wheels - it does not lock. The computer determines when to turn the driveshaft (with another clutch in the "transfer case" if it can be called that - then there is basically a set of clutches that engage and turn the rear axles, again according to the computer's direction.
There is a pretty good description here http://www.hondanews.com/categories/891/releases/891
That states:.
"Ensuring a high level of all-weather stability, traction and control is the Pilot's VTM-4 (Variable Torque Management 4-Wheel Drive) system. Unlike conventional on-demand systems that work only when the wheels are slipping, VTM-4 proactively delivers torque to all four wheels during acceleration for excellent dry-road vehicle dynamics as well as outstanding control in wet, icy and snow conditions. A unique "lock" feature is provided to maximize traction for extremely slippery or "stuck" conditions. A compact transfer case is bolted directly to Pilot's front-mounted transaxle. A two-piece propeller shaft delivers torque from the transfer case to a rear axle drive unit. Two computer-controlled, electromagnetically-powered clutches engage as needed to provide torque to the rear wheels."
I have no idea if both would spin at the same time. |
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| JDKRXW |
quote:
Originally posted by jonaz
[B]No where in the Honda Pilot manual does it say that the Pilot has a locking rear differential. This is a big myth about our Pilots.
Sounds like you may have some rear end issues. The rear axle halfs DO get locked together (I used the term differential lock above for the sake of simplicity).See tfrain's description from Honda above. A quick check to test your VTM-4 is to go to wide street, shift into first gear and hit the VTM-4 button. Then crank the steering wheel all the way over in one direction and accelerate SLOWLY from a dead stop. My Pilot bucks and shudders like crazy because the rear axles are held together with enough force that the rear tires will slip on the pavement going around this sharp corner. |
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| tfrain |
quote:
Originally posted by JDKRXW
Sounds like you may have some rear end issues. The rear axle halfs DO get locked together (I used the term differential lock above for the sake of simplicity).See tfrain's description from Honda above. A quick check to test your VTM-4 is to go to wide street, shift into first gear and hit the VTM-4 button. Then crank the steering wheel all the way over in one direction and accelerate SLOWLY from a dead stop. My Pilot bucks and shudders like crazy because the rear axles are held together with enough force that the rear tires will slip on the pavement going around this sharp corner.
I wouldn't do that too much - Actually I think the manual tells you to only do it on a slick surface (like mud or offroad). The rear end on the pilot isn't very heavy duty at all and depending on how much grip you had on the tires could definitely grenade the rear end. |
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| jonaz |
| I remember when we first got our Pilot, and got it stuck in a snow bank, watching some of the wheels spin with the VTM "locked". We eventually got it unstuck, and so we took it in to the dealer to see if our VTM was broken. They looked it over and said it was fine. They also told me it wasnt a true locking differential. Anyway, being stuck is the only way you will see what Im talking about, but I hope I you never get a chance to prove me right. |
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| tangotango99 |
quote:
Originally posted by JDKRXW
Sounds like you may have some rear end issues. The rear axle halfs DO get locked together (I used the term differential lock above for the sake of simplicity).See tfrain's description from Honda above. A quick check to test your VTM-4 is to go to wide street, shift into first gear and hit the VTM-4 button. Then crank the steering wheel all the way over in one direction and accelerate SLOWLY from a dead stop. My Pilot bucks and shudders like crazy because the rear axles are held together with enough force that the rear tires will slip on the pavement going around this sharp corner.
If you use the VTM-4 on dry surface it will damage the drive-train system. |
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| switch |
quote:
Originally posted by tangotango99
If you use the VTM-4 on dry surface it will damage the drive-train system.
Thanks for letting me know that. Now I will go out and do it. :2: |
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| JDKRXW |
quote:
Originally posted by tfrain
THE VTM-4 system uses a wet clutch to drive the rear wheels - it does not lock. The computer determines when to turn the driveshaft (with another clutch in the "transfer case" if it can be called that - then there is basically a set of clutches that engage and turn the rear axles, again according to the computer's direction.
Not trying to be a smart-ass, but there's no clutch in the transfer case. It is a simple right angle gear box (hypoid gears) driven off the front transaxle's differential carrier. The rear driveshaft turns whenever the vehicle is moving..... forward or backwards 100% of the time.
"VTM-4" describes the control system in the rear differential. The control unit for the diff. is at the back of the truck, beside the jack. Some people don't call the Pilot's rear end a differential, but I do and so does Honda.
The rear axles can definitely be locked together by the electomagnetic clutches in the rear differential assembly.
From page 15-12 of the 2005 service manual
"the operation of the VTM-4 consists of the following functions; vehicle acceleration torque control (VATC), limited slip differential (LSD) and lock control. These functions automatically combine to distribute driving torque between the front and rear wheels when the vehicle is being accelerated or when the wheels are slipping. When the vehicle is stopped and the transmission is in R,2 or 1 positions, the system will fully lock the rear differential clutches when the vtm-4 button is pressed. By design, in lock mode, the torque is reduced gradually at speeds above 6 mph to minimize the load on the 4wd system (this I didn't know untli I read the service manual) |
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| switch |
There should be a nerd smiley. ;)
Does that mean that you be stopped on a slippery surface, engage the VTM while in D1, floor it, and have all 4 wheels spin? |
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| tfrain |
| what about the traction control? Jonaz talked about seeing the wheels spinning "unlocked" - I would think that the traction control would brake the spinning wheel and try to get traction with the other wheel. (I don't think 2003 had traction control did it?) |
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| JDKRXW |
Yes, traction control will brake the spinning wheels, but even with it, if you're stuck, t.c. with the vtm-4 button pressed (and in 1,2 or r), the rear wheels will still spin. The t.c. is being over ridden.
Even on a front wheel drive car with t.c., when stuck, the wheels are still allowed to spin somewhat, so the car can dig itself out. If this was not the case, the vehicle would be stuck all the time in a small amount of snow. |
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| jonaz |
| OK guys, this is a easy way to see how the VTM lock feature really works. Go find a really steep hill, and have your wife or friend try to drive up it with the VTM locked. This way you wont get stuck. If the VTM really locks the rear wheels, you will get to prove me wrong. Watch the front and rear wheels, and see which one is spinning, in the locked, and unlocked mode. |
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| sagaliba |
quote:
Originally posted by tfrain
There is a pretty good description here http://www.hondanews.com/categories/891/releases/891
In that 2003 press release, it says the rear axle will receive a maximum of 50% torque (resulting in a 50/50 split of the torque between front and rear). But the tech spec sheet my dealer copied for me for my 2007 Pilot says the maximum torque delivers to the rear is 60% (a 40/60 split between front and rear). I do not know which year they made the switch though.
In essence, for the 2007 Pilot, the torque for the front is varying between 40% and 100%, while the rear will vary from 0% to 60%.
Note: when VTM-4 is in the "Lock" mode, it delivers the above-mentioned preset maximum amount of toruqe to the rear . |
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| N_Jay |
quote:
Originally posted by sagaliba
In that 2003 press release, it says the rear axle will receive a maximum of 50% torque (resulting in a 50/50 split of the torque between front and rear). But the tech spec sheet my dealer copied for me for my 2007 Pilot says the maximum torque delivers to the rear is 60% (a 40/60 split between front and rear). I do not know which year they made the switch though.
n essence, for the 2007 Pilot, the torque for the front is varying between 40% and 100%, while the rear will vary from 0% to 60%.
There is no way to accurately control or measure the torque split, so nothing may have changed but the marketing spin. |
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| xGS |
quote:
Originally posted by switch
There should be a nerd smiley. ;)
Will this suffice? |
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