Out in the boonies we found a Jeep Grand Cherokee stuck in a ditch running down the road. the left front and right rear wheels were off the ground because of the way the ditch ran down the road. No matter what he tried, he was stuck. We pulled him out and showed him what a air-locker was and why he might want one. Does this happen to stock 4Runners, too?
Is a Grand Cherokee a Jeep?
- Thread starter Larry
- Start date
Register to hide this ad
Thai
Elite Member
This is called, "cross-axle" situation. It should not happen with the 4runner's ATRAC system. You just need to keep steady pressure on the gas pedal and ignore ATRAC's blinking lights and annoying noise. It will get you through.
The only time that i would evision this to be an issue IF you're crossing this ditch while going up a steep hill at the same time. In this situation, the torque "transfer" from ATRAC (to the wheel with traction) is not enough to push the 4runner uphill. (Torque transfer is never 100% with ATRAC or anything else not called a locker.)
As for the Jeep GC's problem, this is well-documented. See this thread:
http://www.toyota-4runner.org/showthread.php?s=&threadid=57
Scroll down to midway. I am hoping that the new electronic Variloks are better than the old one!
The only time that i would evision this to be an issue IF you're crossing this ditch while going up a steep hill at the same time. In this situation, the torque "transfer" from ATRAC (to the wheel with traction) is not enough to push the 4runner uphill. (Torque transfer is never 100% with ATRAC or anything else not called a locker.)
As for the Jeep GC's problem, this is well-documented. See this thread:
http://www.toyota-4runner.org/showthread.php?s=&threadid=57
Scroll down to midway. I am hoping that the new electronic Variloks are better than the old one!
Given the proper idiot behind the wheel, any vehicle can get stuck in almost any situation.
Not sticking up for the JGC, but you didn't specify which year, model, and 4wd system it had. Depending on the year, I think the GC had at least 3 different transfer case options, Control-Trac (part time), Quadratrac I (full time, single-speed) and Quadradrive(full time, two-speed) If it was a part-time transfer case model, then what you describe is exactly what I would expect. (They had limited-slip rear diffs, but it's not very effective)
The 4Runners have essentially the same 4WD system across all trim packages for the 4-gen, which should get them out of that situation. But like I said, given the proper idiot.
--Mike
Not sticking up for the JGC, but you didn't specify which year, model, and 4wd system it had. Depending on the year, I think the GC had at least 3 different transfer case options, Control-Trac (part time), Quadratrac I (full time, single-speed) and Quadradrive(full time, two-speed) If it was a part-time transfer case model, then what you describe is exactly what I would expect. (They had limited-slip rear diffs, but it's not very effective)
The 4Runners have essentially the same 4WD system across all trim packages for the 4-gen, which should get them out of that situation. But like I said, given the proper idiot.
--Mike
So, when one buys a Jeep GC, the salesperson will explain all the implications of ordering each of the three different systems, and will draw on his/her vast experience in off road operations so the buyer will know how each system fails and leaves one stranded in the outback. I can tell you that posi-traction (insert you own pet name) sucks. A driver controlled locker is the sure way to go. And I don't like all this complication over four wheel drive systems, especially when a salesperson only knows that they don't get paid unless you buy, to hell with what you need, here's the pen... sign.
JB.
New member
Thai said:
I'll try to be more clear.
Given the huge reserve of torque a 4th gen has even on the steepest of hills, I'd consider it a bad design flaw if ATRAC couldn't make enough torque available to one front and one back wheel to continue the climb regardless of grade. So bad a flaw, in fact, that I'd have to see it to believe it.
Thai
Elite Member
JB. said:
Well, i am sure someone has done something like this in the past and can share us a video.
Disclaimer: Hummer H2 may not have the same calibration in it's ATRAC system, but i will use it as an example. According to Hummer literature, the H2 will be able to make up a 10% grade with ONE wheel traction. To extrapolate, i am sure that the H2 can make up a steeper grade hill with two wheel traction, but i doubt that it would be anywhere near 100% grade (45 degree slope).
Larry said:
Yep, that's why I own a 4Runner and not a JGC! I liked the idea that I can have the same drivetrain on my SR5 as the guy that buys the Limited. Somehow Jeep got it into their head that if you want full-time 4-wheel drive, you must also want leather seats, and seat heaters, and navigation, and .... well you get the idea. Seemed rather dumb to me that the model with the best 4WD system in their lineup is the least likely to be taken off-road.
And yes, I agree, limited-slip, posi-trac, trac-loc, etc.. diffs suck, that's why my Wrangler has ARB's front and rear.
--Mike
Thai
Elite Member
Hitman said:
However, i can tell you that MOST people who buy SUVs these days do NOT do their research on the 4wd system. Think about all those soccer moms out there with Hummer H2, TLC/LX470, or G-wagens. Only a few know how to use it...and a small percentage of THAT group will actually use it once in their lifetime on an actual off-road trail!
Where do you think Land Rover gets their image nowadays?? Or Hummer or Jeep for that matter. If you notice in all of these brands, there is only ONE vehicle that defines the brand...the rest of them just lives under that image. Jeep = Wrangler. Land Rover = Defender. Hummer = H1/Humvee.
JB.
New member
I, too, would love to find out what percentage of torque is going to the one wheel in the H2. The V8 4runner has about a 30% better torque/weight ratio so all else being similar, it should put more power to a wheel. Even the V6 has a considerable advantage at about 20%. I'm starting to fully appreciate how important torque is when traction control is involved. Interesting subject.
briandunning
New member
We just bought our first 4Runner last week, which replaces our beloved '01 Grand Cherokee Limited. It was a GREAT rig, and is definitely a real Jeep, unlike its newborn retarded IFS '05+ little brother.
Ours was mostly stock and it was still a monster at getting places where even some modified rigs couldn't go. And we did it in comfort & splendor...
My only gripe was with our QuadraDrive system - basically three electronically controlled limited-slip slushboxes. From personal experience, I can assure you that it is a one-wheel-drive system. I have video evidence of this.
I wrote into Four Wheeler once asking if it was possible to put a locker in the back (since the whole system is electronic), and the answer was yes, but only by having a complete custom rear axle built. So I never did that, and suffered with one-wheel-drive.
I am in the process of building an old Cherokee to be our REAL trail rig - the wife doesn't need body damage on her new Toy.
Ours was mostly stock and it was still a monster at getting places where even some modified rigs couldn't go. And we did it in comfort & splendor...
My only gripe was with our QuadraDrive system - basically three electronically controlled limited-slip slushboxes. From personal experience, I can assure you that it is a one-wheel-drive system. I have video evidence of this.
I wrote into Four Wheeler once asking if it was possible to put a locker in the back (since the whole system is electronic), and the answer was yes, but only by having a complete custom rear axle built. So I never did that, and suffered with one-wheel-drive.
I am in the process of building an old Cherokee to be our REAL trail rig - the wife doesn't need body damage on her new Toy.
briandunning
New member
I am curious to know why you say this. The "default" setup among serious wheelers is a Detroit Locker in the back and an ARB in the front, on the principle that it's common to need a locked rear and rarer to need a locked front. There are many times in my JGC I would have given my left nut for a locker in back.
Similar threads
