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Toyota 4WD systems explained

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Comments

  • vtdogvtdog Member Posts: 163
    I am considering a Tacoma 4wd. I am interested to hear from people who own the 4cyl version to see if they think there is adequate power for general use (don't tow, but do drive on dirt roads and minor trails) or is the 6cyl needed due to the increased weight of the 4x4. I am interested as the 4cyl version is rated for much higher mpg by the EPA.

    Thanks
  • tuttie01tuttie01 Member Posts: 3
    when I put my 2009 truck in Lo 4 it beeps can anyone tell me y?
  • tuttie01tuttie01 Member Posts: 3
    I had a 1999 4x4 with a 4 cyc just gave it to my brother was good for everything I did even towing.
  • kingfans1kingfans1 Member Posts: 137
    I think when you are drivin in heavy snow, you use 4wd low + lock center diff...
  • wwestwwest Member Posts: 10,706
    The center locking clutch, spline, dog clutch, often doesn't engage without slight/slow forward or reverse movement. The beep is probably a warning to you that the dog clutch is not yet engaged.

    Same thing, often, when unlocking.
  • greengreen Member Posts: 15
    It'll beep if you're not in neutral. You also need to be stopped.
  • bosmabosma Member Posts: 1
    Can anyone please simply explain how to use the various 4 wheel drive options on the 05 V8 4Runner? Literally.
    There is so much info on slip/no slip, locks but without traction control to some diferential.........? Wow.
    You guys know what your talking about and for a simple gut like me it gets a bit confusing.
    Now to my questions that I hope is clear enough to understand.
    Aperrently my 4Runner is always in 4 wheel drive. O.K.

    There is a silver knob to the right of the steering wheel and a black button to the left of the steering wheel.
    My understanding is that there are two other levels of 4 wheel drive that can be applied to the already 4 wheel drive that the car is always in.

    How do I get the car into the optional 4 wheel drives. Literally. Does the car need to be in neutral or park to perform these stunts? What knob or button do I engage first,second or third. It sounds like driving a submarine.

    After I apply these tecniques so generously given by you, what simply happens to the car? Lol.
    Ex: 1st- Turn the knob to 4W low then press the buton, open the sun roof half way and this will give you X.
    All four wheels are now locked Or You now have low tourq for good pulling power etc....
    i've read quite a bit on do's, dont's and bennefits in different 4 wheel drive settings but have no idea how to get the car to those settings.
    Please Help Me!!
    Thanking you all in advance.
    Dave.
  • greengreen Member Posts: 15
    Since you have full time 4WD, you may never need the other settings. It is, however, a good idea to use low range a little a few times a year to keep it working properly.

    The silver dial is for low range gearing. You need to be in neutral and stopped to engage. It's for extra pulling power or low speed control.

    The black button with a picture of 4 wheels on it locks the center differential which does 2 things. 1. Locks the mechanical connection between the front and rear axles for better traction. 2. Defeats the electronic feature that limits throttle output (mostly or only an issue in high range). You can press this button stopped or in motion. If you're stopped, it sometimes requires a little wheel, throttle, or shifter motion to complete. The following rule is over-simplified but it works as a rule of thumb. Don't lock it unless the road surface is slippery: snow, dirt, slush etc. If you have to have it locked on pavement, avoid tight turns especially at low speed.
  • blueduckblueduck Member Posts: 1
    I have a 95 limited 4runner and have been having trouble with my 4wd. We've had a lot of snow lately and its been hard to get around because its very sluggish. The steering seems a lot stiffer, and once I pass 20mph it feels like all 4 wheels are moving out of sync with each other which results in jerky movements side to side and front to back. It makes it very difficult to build up speed and stay in just one lane. I'm guess some sort of differential issue? I'm hoping I just need to grease something but chances are its probably more than that. Any ideas?
  • wwestwwest Member Posts: 10,706
    If you are not driving on a CONSISTENTLY/"continuously" slippery surface that might be an SOP effect of a 4WD with a locked center diff'l. And it is NOT advisable, actually UNSAFE, to be in 4WD, locked center differential, once you're up to a reasonable traveling speed.
  • fullcirclefullcircle Member Posts: 1
    I recently purchased a '01 4Runner from my local dealer. Before purchasing the vehicle, I checked that the 4wd system was operating as per the owner's manual instruction. As it should have, when in 4wd, the ESC OFF and center diff indicator lights lit when the 4wd button on the side of the selector was pushed. A few months and about 2k miles later, I did a quick check of the 4wd system to make sure everything was getting lubricated when I noticed that when in the Low range, there was nothing happening once I pushed the 4wd button (I check this mode when fully stopped). Unlike before, the ESC OFF and center diff lock indicator lights do not come on when the button is pushed. Am I missing something here? I know it worked as the owner's manual said it should when I checked the system the first time. Now, nothing at all is happening when I push the 4wd button.
  • wwestwwest Member Posts: 10,706
    It is a rather rare event that the front driveline spline shaft "dog" clutch will engage with the vehicle not in motion, you typically have to be moving or move the vehicle slowly forward or reverse. ABS/TC/VSC/etc, will not be disabled until the spline clutch is actual in the engaged position.

    Getting the 4WD clutch to engage in low, "granny grunt" range without the vehicle in motion is even worse and will often be disabled unless the shifter is in one of the lower gears.
  • toyotapilottoyotapilot Member Posts: 10
    I'm thinking of getting a 2005 RAV4 with manual transmission. I'm finding more 2 wheel drive cars than 4x4, plus they cost a lot less. Are 2wd RAVs nearly as good in the snow as 4x4s and isn't that about the only time you'd use it? Thanks!
  • wwestwwest Member Posts: 10,706
    Since the RAV4 is FWD, or at best F/awd, the manual transaxle was dropped in later models for safety reasons, to protect the unwary or inexperienced drivers. VW has just announced a solution for that potential problem and so we may soon again see stick shifting in more FWD and F/awd vehicles.

    The RAV4 is a F/awd system NOT/NEVER a 4X4 or 4WD.

    For the RAV4 "2WD" is really FWD and I would NEVER advise anyone north of te snow line to purchase one without VSC/TC/ABS/BA/EBD/Etc, and even then NEVER with a manual transaxle.

    If you have a HIGH experience level/background in the operation of FWD in wintertime conditions to begin with, and then transition to one with a stick shift, then maybe.
  • toyotapilottoyotapilot Member Posts: 10
    Does anyone in this forum have experience with a two-wheel drive RAV4 (ideally 2004 or 2005) in the snow? I think both versions of the 2005 RAV4s (2-wheel drive and 4x4) come with VST/TCS/ABS/EBD and all that other good stuff, but I'd like to know if I should only consider the 4x4 models since I live in Connecticut. I had a 2-wheel drive 1997 RAV with the 4-wheel drive button that made the car great in the snow.
  • sabre364sabre364 Member Posts: 18
    If you turn the knob to 4hi in a 4wd V6 4runner (say 2007-2009), you can operate it on dry pavement correct? Only if you lock the center diff and/or put it in 4 low does it need to be turned off?
  • wwestwwest Member Posts: 10,706
    I doubt that..but...

    Don't do that until you're ABSOLUTELY sure.

    Some 4runners come with an AWD mode but I'm pretty sure the center diff'l gets locked in 4-hi and 4-low mode.
  • greengreen Member Posts: 15
    All 4th gen (03-09) 4WD 4Runners have a Torsen locking center differential. You can run in 4WD without the center locked on any surface in high or low range. The center lock is a separate button. If this sounds very cool to you, you're right. It is very cool.
  • wwestwwest Member Posts: 10,706
    "...You can run in 4WD...."

    I would take greater care in your advice.....

    Down at the nuts and bolts level there is a GREAT deal of difference between the "AWD" (R/awd) mode provided by the Torsen (Torque Sensing) diff'l and a locking center diff'l used in "TRUE" 4WD mode.

    The question was too specific, "can I use 4-hi" for your answer to be "on point".

    Yes, a Torsen center diff'l is a STELLAR method of providing a R/awd system, but it should NEVER be described in the context of ...."4-hi".
  • greengreen Member Posts: 15
    wwest - Down at the nuts and bolts level there is a GREAT deal of difference between the "AWD" (R/awd) mode provided by the Torsen (Torque Sensing) diff'l and a locking center diff'l used in "TRUE" 4WD mode.

    Okay, but it's a non sequitar.

    wwest - The question was too specific, "can I use 4-hi" for your answer to be "on point".

    I provided information for understanding all the transfer modes which, of course, also answered the question.

    wwest - Yes, a Torsen center diff'l is a STELLAR method of providing a R/awd system, but it should NEVER be described in the context of ...."4-hi".

    It's Toyota's term, tell them.
  • greengreen Member Posts: 15
    sabre364 - "If you turn the knob to 4hi in a 4wd V6 4runner (say 2007-2009), you can operate it on dry pavement correct? Only if you lock the center diff and/or put it in 4 low does it need to be turned off?"

    If, perchance, my 1st reply was unclear the answer is yes, you can operate on dry pavement with the knob in 4hi. 4lo, too, as long as the center diff is unlocked.
  • wwestwwest Member Posts: 10,706
    But the way I read the 2007 4runner owners manual the center diff'l is ALWAYS locked in 4-hi and 4-lo.

    Additionally it appears there were three driveline options in 2007 and only the multi-mode option included a R/awd functionality.

    And for some reason Toyota has discontined use of the Torsen term prior to 2007. I see no significant difference in the mechanical make up of the transfer case so I assume the Torsen is still used. Maybe a clone, patent expired.
  • greengreen Member Posts: 15
    wwest - But the way I read the 2007 4runner owners manual the center diff'l is ALWAYS locked in 4-hi and 4-lo.

    Are you sure it was a 4Runner manual? Here are some paragraph headings, verbatim, from page 168 of the 2007 manual for the multi-mode four-wheel drive models.

    “H2” (high speed position, two-wheel
    drive, center differential unlocked):

    “H4” (high speed position, four-wheel
    drive, center differential unlocked):

    “H4” (high speed position, four-wheel
    drive, center differential locked):

    “L4” (low speed position, four-wheel
    drive, center differential unlocked):

    “L4” (low speed position, four-wheel
    drive, center differential locked):

    wwest - Additionally it appears there were three driveline options in 2007 and only the multi-mode option included a R/awd functionality.

    Yes, for 2007 as well as the other years. Driveline options are 2WD, Multi-mode 4WD with 2WD capability (V6), full-time 4WD (V8). All the headings from above, except H2, apply to the full-time 4WD.
  • wwestwwest Member Posts: 10,706
    Green is correct.

    For the 2007 model there is a separate switch for un/locking the center diff'l regardless of driveline model, plain 4WD or Multi-mode. I seem to remember that one of these driveline options was not available with the V6.
  • nedzelnedzel Member Posts: 787
    On the 4th Gen 4Runner V6, you can drive on pavement in 4wd high, or 2wd hi. The center differential should be unlocked.

    You should only use 4wd low and/or lock the center differential when you are off road.

    The 4th Gen 4Runner V8 has basically the same drivetrain, but does not have the option for 2wd high.

    For the 2007 model there is a separate switch for un/locking the center diff'l regardless of driveline model, plain 4WD or Multi-mode

    That locking switch has remained the same throughout the entire run of 4th gen 4Runners, both V8 and V6. It is a pushbutton on the lower portion of the dash, to the left of the steering wheel.
  • canddmeyercanddmeyer Member Posts: 410
    I've been running my 2003 4Runner V6 4wd in 4Hi unlocked since I bought it. There have been zero problems.
  • wwestwwest Member Posts: 10,706
    "..You should only use 4wd low and/or lock the center differential when you are off road.."

    The center differential should ONLY locked as above or in low traction, oil/water(rain) slicked, slippery roadbed, or wintertime adverse roadbed conditions. Even in these additional low traction conditions it is NOT a good idea to keep the center diff'l locked once underway, traveling at a decent speed, say above 15MPH.
  • nedzelnedzel Member Posts: 787
    "The center differential should ONLY locked as above or in low traction, oil/water(rain) slicked, slippery roadbed, or wintertime adverse roadbed conditions."

    I would not lock it on rain-slicked roads or snow-covered roads. The 4Runner becomes quite tail-happy when you lock the center diff and there is simply no need to lock it on your typical rain-slicked or snow covered road. I've put 80,000+ miles on my 4Runner and only lock the center diff when I go off road.
  • wwestwwest Member Posts: 10,706
    "....4Runner becomes quite tail-happy..."

    Don't you have that a bit backwards....??

    With the center diff'l locked the F/R torque bias is neutral, other than F/R weight bias, and it should be just as "front-happy" as rear.

    On the other hand with the center diff'l locked you lose all the "nanny", "watchover your shoulder" electronic aspects, ABS, VSC, etc, and maybe that's why you appear to have had a tail-happy experience.

    But as I said, the center diff'l should NOT remain locked once underway.
  • nedzelnedzel Member Posts: 787
    Don't you have that a bit backwards....??

    No, I don't. I've driven my 4Runner in the snow, with the center diff locked and with it unlocked. I've driven it with all-season tires and snow tires. I've put 80,000 miles on it. Have you driven a 4th Gen 4Runner in the snow with the center diff locked?

    With the center diff'l locked the F/R torque bias is neutral, other than F/R weight bias, and it should be just as "front-happy" as rear.

    You can argue about how it "should" or "should not" handle. I can tell you how mine does handle, because I've driven it in the snow with the diff locked. With the center diff locked, when driving in the snow, if you get heavy on the gas in a turn the rear steps out quickly. Given that the 4Runner has a lot of weight over the front wheels and far less on the rear, it is perhaps not unsurprising that with equal torque to the front and rear axles that the rear will lose traction before the front.

    On the other hand with the center diff'l locked you lose all the "nanny", "watchover your shoulder" electronic aspects, ABS, VSC, etc, and maybe that's why you appear to have had a tail-happy experience..

    You just might want to re-read your technical manuals. You do not lose all the nanny electronics when you lock the center diff; you lose the VSC. You don't lose ABS and you don't lose the traction control. Which, in some ways, is unfortunate. There are times when I'd like to lose ABS and traction control.

    I learned to drive in Chicago, driving a 1969 Ford Falcon, 1970 Ford Galaxie 500 station wagon, and a 1972 Mercury Capri. When driving the Capri, in particular, my brother and I liked to hang the back out in the snow. It was very, very controllable, far easier to control than my 4Runner.
  • wwestwwest Member Posts: 10,706
    I'm going to stand by my statement, but let me first give you my definition of "tail-happy"...

    Tail-happy is when you are driving STRAIGHT along and step on the gas and the rear tries to get in the lead, very common to RWD. On the other hand, in your case. diff'l locked, if you happen to be turning at the same time then inertia comes into play and the rear end will skid toward the outside of the turn while the front plows to the same "degree".

    So your 4Runner, with the center diff'l locked, and equal tires on all four, will have neutral "happiness", just as the Toyota design engineers intended.

    I'm surprised at ABS, and TC, remaining enabled since BOTH drivelines MUST turn in synchronization and that compromises the functionality of ABS and TC.
  • nedzelnedzel Member Posts: 787
    wwest: I own a 4Runner. I have driven a 4Runner in the snow, with the center diff locked and unlocked. I have real, live experience with the vehicle. You have, what? Theories and supposition? Go drive one in the snow with the center diff locked and unlocked. Then come back and tell us about it. Until then...
  • wwestwwest Member Posts: 10,706
    "..go drive one in the snow..."

    How about miles upon miles on mountain passes in WA, OR, ID, and MT, more often packed snow than not. Except for those many early morning drives up the mountain in order to be the first to lay "tracks" in the freshly fallen snow.

    I can't imagine that the 4runner drive system and handling dynamics in various drive configurations would be that much different from my '85 Jeep nor my '92 Jeep, both Cherokee Limited's with RWD/"AWD"/4WD/4X4 modes. Maybe as much as 150,000 miles overall, and quite a few NW winters with Ski trips.

    The '92 is still doing duty in the "family" on a cattle and wheat ranch in north central MT.

    I admit I never found much, if any, use for the AWD mode, 4 wheels driven but center diff'l open, and I probably never found use for the 4-lo mode.

    But I did find lots of use for the 4WD (diff'l LOCKED) mode, often with rear chains installed and sometimes with all four chains.

    Oh, I always removed the ABS fuse during the summer.
  • greengreen Member Posts: 15
    "But as I said, the center diff'l should NOT remain locked once underway."

    You've repeated that idea, with emphasis, a few times (even branding it unsafe) so I'm curious to know your reason. I don't expect to hear anything I haven't heard, but your position seems to be even more extreme than the standard "NEVER lock on dry pavement" warning which is already over simplified, imo.
  • wwestwwest Member Posts: 10,706
    Once you're underway the usefulness of the extra "drive" traction is mostly negated by momentum. You may also note that with more modern 4WD systems the ABS & VSC are disabled in 4WD mode. In some cases 4WD mode itself is disabled if you apply the brakes or if VSC activates. Traditional 4WD systems use a spline or dog clutch which cannot be quickly, reliably, disenaged, so these "features" are kept disabled.

    Leaving a 4WD system engaged once underway is a lot like driving a FWD, or F/awd, patently UNSAFE. On an adverse condition roadbed, slippery roadbed, it is highly desireable to dedicate the front tire traction solely to directional control. With a locked center diff'l 50% of the engine drive torque, or ~70-80% of engine compression braking, is applied to the front wheels, leaving not much of the already low front traction coefficient for maintaining directional control.

    IMMHO the best feature of ANY AWD system would be to remove all engine leading or lagging torque from the front tires as soon as the stability control system indicates a yawing condition, the vehicle is NOT following the "line" set by the stearing angle of the front wheels.

    There is as yet, to my knowledge, NO FWD based AWD system that can accomplish that task.

    The best "simulation" is to put your "traditional" 4WD system into RWD mode.
  • greengreen Member Posts: 15
    Thanks for the reply.
  • nedzelnedzel Member Posts: 787
    wwest, so, in other words, you haven't driven a 4Runner in the snow. Go drive one and then get back to us.
  • wwestwwest Member Posts: 10,706
    Assuming 4 good tires in both cases, what makes you think there is something to be learned driving a 4runner vs the years and miles, snow and ice miles included, spent driving the RWD/4WD(AWD)/4X4 Jeeps...??

    Granted, the 4runner's AWD mode, 30/70 F/R torque distribution offers additional capability over the Jeeps, but then I get to throw in my years and miles, again with snow and ice miles, in my '94 AWD Ford Aerostar, 30/70 F/R unless slippage at the rear occurs in which case it goes to 50/50 for the next few minutes.

    And if you happen to be bringing up the TC/VSC capabilities of the 4runner, NOTHING beats the PSM in my 996 C4 in that category.
  • nedzelnedzel Member Posts: 787
    WWest, in the winter I run snow tires on the 4Runner. I have four Nokian Hakkapeliitta snow tires, all with good tread.

    I've driven the 4Runner in snow, with and without the center diff locked. You haven't. You can speculate and theorize about how you think it should handle in the snow, but you haven't driven it. I have. So please stop telling me about how it handles. I know how it handles. You don't. You haven't driven it.

    I won't speculate about how your Jeeps, with different drivetrains, different suspensions, and different weight balances, handle in different conditions and different 4WD/AWD modes. You've driven them. I haven't.

    Feel free to brag about your 996. I'm sure it is a very lovely car. But I fail to see how that is germane to how a 4Runner handles in the snow with the center diff locked.
  • wwestwwest Member Posts: 10,706
    The 911 isn't germane to driving the 4runner with the diff'l locked, only unlocked with VSC and ABS enabled.

    "...please stop telling me how it handles..."

    We seem to have off-track pretty much solely on the issue of your 4runner being "tail-happy" with the center diff'l locked. Frankly I think anyone of actual knowledge or long experience will tell you that should NOT happen.

    But again, just what is your definition of "tail-happy"...?

    Mine would be: "f you step on the gas traveling straight down the road the engine torque applied to the rear will often result in the rear trying to lead the front. Pretty much SOP for RWD or R/awd but IMMHO NEVER in 4WD with the center diff'l locked.

    Have you had a mechanic check and certify that your 4runner really does have the center diff'l LOCKED when the indication lights up...??
  • wwestwwest Member Posts: 10,706
    Maybe I see..

    With the center diff'l locked ABS is disabled and since frictional braking is ALWAYS biased toward the front your 4runner will have a strong tendancy for the rear coming "about", especially when "braking" while traveling downhill. To some extend engine compression braking will have the same effect.

    Your 4runner is not necessarily any more tail-happy with the diff'l locked than any other non-ABS equipped vehicle, RWD/FWD, etc, etc.

    Yet another reason for NOT using the locked mode once underway at a decent speed.

    One of the more common hazards, inadvertent engine "braking" of FWD and/or F/awd vehicles.
  • 2toyotas2toyotas Member Posts: 104
    Nedzel, You will never win with Wwest. He still does not know that all toyota SUV,s, and trucks keep ABS and traction control active when in 4 locked mode. even in my tundra, which is part time 4wd, Traction control and ABS works when locked in 4WD. On new Tundras you can keep VSC active when in 4 locked. You are wasting your time because Wwest keeps arguing his point whether he is right or not. Just look at some of are previous posts. I gave up.
  • wwestwwest Member Posts: 10,706
    When the center differential is locked the front and rear drivelines MUST turn at equal rotation. Even if ABS were left enabled, which I do not believe, it could not be fully functional. The same goes for VSC. How could VSC apply differential braking, something it is often required to do, in the rear vs the front vs if the driveline has them locked together, braking the rear would automatically be "reflected" at the front.

    The 2009 4runner owners manual indicates that VSC is disabled when the center diff'l is locked. Could find no reference to ABS one way or another.
  • usedcar3usedcar3 Member Posts: 5
    Beginning with the 2000 model year Land Cruiser, Toyota began using a new 4WD system called ActiveTrac. This same system was incorporated into all 2001 4Runners and the new 2001 Sequoias. The same basic system has also been used in the Mercedes M Class as well as post ‘99 Humvees. :(
  • nedzelnedzel Member Posts: 787
    "With the center diff'l locked ABS is disabled and since frictional braking is ALWAYS biased toward the front your 4runner will have a strong tendancy for the rear coming "about", especially when "braking" while traveling downhill. To some extend engine compression braking will have the same effect. "
    Actually, I experience it under heavy acceleration, in snow, with the center diff locked.
  • steverstever Guest Posts: 52,454
    (cross-posted to 4WD & AWD systems explained)

    "it looks like Toyota has given the Trail Grade 4Runner as much four-wheel-drive capability as anything else sold in the U.S, giving Toyota the widest and deepest range of serious 4x4s (FJ, 4Runner, Land Cruiser) in the industry."

    Is the 2010 4Runner Trail Grade the Best 4x4 Package Sold in the U.S.? (Straightline)

    image
  • nedzelnedzel Member Posts: 787
    Unfortunately, there is a very serious error that article. Only the Limited model comes with the Torsen center diff. The SR5 and Trail Editions do not have a center differential. You can see that in the document released by Toyota: http://pressroom.toyota.com/pr/tms/toyota/document/2010_4Runner_Product_Info.pdf- ?ncid=11092

    What this means is that here in the Northeast, when roads go from dry to wet to snow covered and back in just a few hundred yards, you can't use 4WD in the SR5 and Trail Editions. Not good, a big step backwards from the 4th Generation, and a huge disappointment.

    Steve, I hope you will ask the author of that article to contact Toyota to clarify that the Torsen center diff is not available on the SR5 and Trail editions, and then have him clarify the article explaining the implications. As it is, the article is very misleading.
  • steverstever Guest Posts: 52,454
    If you got my email, you know that I forwarded your comments to editorial.

    Sometimes manufacturer brochures are wrong and sometimes the "official" information contradicts itself. Press releases are notorious for getting things screwed up too.

    I'm curious to see what the story is here.
  • stateofmainestateofmaine Member Posts: 30
    i'm a mainer and currently own a 2006 V8 4runner (full-time 4WD) which is indispensable during the winter... i'm VERY interested to know what the reality is with the new 4runners' (lack of?) center differential (SR5 and Trail Edition) and if the 4WD can be used on-road... i've literally been waiting to buy the Trail Edition, but if it's going to be less sure-footed than my current 4Runner from December - April (yeah, that's almost half the year) i don't think i'll getting a new Toyota. :(
  • steverstever Guest Posts: 52,454
    Here's another Toyota press release:

    "SR5 and Trail 4x4 models have a two-speed lever-operated, part-time system with neutral position, while the 4Runner Limited is equipped with full-time, four-wheel-drive with a locking center differential and employs a three-mode, center console-mounted switch. The new 4Runner is also equipped with a stronger rear differential over the previous model, thanks to a gear ring that has increased in size from 7.87 to 8.18 inches.

    To enhance grip, the A-TRAC system is now standard equipment on all 4x4 models. The system can distribute driving force to any one wheel in contact with the ground, making terrain irregularities and slippery patches transparent to the driver. An electronic-locking rear differential is standard on the Trail grade. Axles house 3.73 gears, or 4.56:1 with the 2.7-liter engine and the differential housings have improved seals for better resistance to mud and water.

    Toyota’s Crawl Control (CRAWL) feature is standard on the Trail grade. CRAWL is an adjustable electro-mechanical system that can be tuned to match the terrain by selecting any of five speed levels. The system maintains an appropriate speed that keeps the vehicle under control and minimizes the load on drivetrain and suspension components. The CRAWL feature helps make traversing difficult terrain easier and safer. With the transfer case shifted into low range, Crawl Control regulates engine speed and output (along with braking force), to propel the vehicle forward or in reverse at one of the five low-speed settings. This allows the driver to maintain focus while steering over very rough level ground or steep grades, without having to also modulate the throttle, or brake, pedals.

    The Trail grade also features a Multi-Terrain Select system which allows the 4x4 operator to dial in wheel slip control to match the terrain. In loose terrain such as mud and sand, more-than-normal wheel slip is permitted, allowing wheel-spin to work in the vehicle’s favor. On bumpy moguls, or solid rock, wheel slip is minimized and the system acts more like a limited slip. The Mogul setting is for any extremely uneven terrain, such as V-ditches, slopes, and ridges, uphill or down."
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