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The best 4wheel drive system is...

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ColoradoMan

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Discussion starter · #1 ·
Before I start, this is only for new jeeps...

The winner, in my opinion is freedom drive 2. It is the most efficient of all the 4wheel drive/awd options jeep has to offer. The part that makes it most efficent is in 2 wheel drive mode it only sends its power to the FRONT wheels. Sending power to the front and back (some grands) or just the back (wrangler, liberty) decreases efficiency and thus decreases mpgs. If power is being sent to the rear wheels at all it has to turn the whole drive shaft decreasing performance and mpgs.

In 4 wheel drive mode it does great traction wise with its brake lock technology. It is responsive in how quickly it stops frictionless spinning tires and can be considered a true 4 wheel drive since it delivers power to the tires that need it.

FD2 also has a decently low gear ratio... It would be nice if it was lower but it seems to work fine.

I wish they would apply the FD2 technology to all jeeps, it would be cool to see one on the wrangler.
 
#2 ·
It all boils down to simple physics. It's easier to pull from the front than to push from the back. Add to that the fact that weight from the engine is over top of the front drive wheels makes for more traction than rear wheel drive wheels.

That said, it's unlikely that FDII will ever be put on a Wrangler. I don't see Chrysler/Fiat changing something that has sold well as is for years.
 
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#3 ·
I posted on another thread that I just got home from a 3500km trip to Idaho and Montana with some of the worst winter driving roads I have ever seen. The Patriot was absolutely awesome and far superior and safer on snow and icy roads than our 99 Cherokee with Part Time Command Trac 4X4 and without ESP. Even when I got high centered in 2' deep snow at Lookout Pass the Patriot performed and I have FD1.
 
#4 ·
ColoradoMan said:
FD2 also has a decently low gear ratio... It would be nice if it was lower but it seems to work fine.
Click to expand...
Probably somewhat predictable but I'll disagree. Against its competition FD is great. But against other Jeep systems it falls short.

First, and my biggest gripe, is even in FDII it is not geared low enough. My point of arguement is that low range in FDII 19:1 is about equal to a wrangler with the 4.11 rear end in high range. This is fine quite often but even a command Trac wrangler has a low range that is 2.72 times lower. Typically you really don't need the torque but the low speed gives you much more control. The rock trac is about 4 times lower than FDII.

Secondly, FD does not truly lock the front and rear axels together. Perhaps I'm just whining but I want a "locked" transfer case to stay locked until I release it. FD can unlock on its own without you knowing and the clutch could potentially slip.

Third, brake lock diffs are a good substitute to a traditional limited slip, it does not compare to traditional lockers. BLDs do a good job of matching left and right wheel speeds but a locker forces both wheels to turn at exactly the same speed, if they aren't it's because your stuff just broke.

So... What is the best Jeep 4x4 system in my opinion? For pure off road use, easily Rock Trac. 4:1 gears puts you into stupid slow mo mode. The NVG241J t-case comes from the factory with a fixed rear yoke, something the command Trac owners must upgrade to at around 4 inches of lift to prevent their slip yoke from falling off or breaking. The NVG241J also has 32 spline shafts from the factory as well as other beefy components. For comparison, the t case used in ram 3500s weighs about half that of a rubicon's tcase. Add in stupid strong axles with front and rear selectable lockers, no one makes a stronger drivetrain for a consumer vehicle.

For a vehicle that is going to be driven on the street and off road, my favorite Jeep system is quadradriveII. It has a true 2.72:1 low range and while I prefer lower it is good enough for most situations. It uses a clutch pack to "lock" the center diff which I don't like for off road but this allows the system to be in a near 50/50 split in normal driving conditions. FD starts as front wheel drive which is good for mpg but a 50/50 split is better for traction. What makes quadradriveII unique though is the automatic front and rear lockers. Not as great off the road as selectable lockers, automatic lockers are still far greater than BLDs in terms of moving the wheels at exactly the same speeds.

In my mind this discussion comes down to three criteria (ignoring longevitey):
1) Fuel efficiency
2) low speed control
3) initial traction

Initial traction I'll define as driving down the interstate with potential for ice

Clearly FD wins in fuel efficiency, it is lighter and front wheel drive, but it loses in low speed control and initial traction unless you thought to pull the lock lever and were traveling less than 30 mph.

Rock trac (and command Trac) is heavy and not fuel efficient. They provide good (or excellent in the case of rock Trac) low speed control however unless you had the foresight to pull the system into 4x4 they are bad on initial traction and even if you did engage 4x4, on ice 4x4 is worse than an awd setup.

QuadradriveII is heavy and while always operating in a near 50/50 split is great for initial traction it eats up the fuel. With a traditional low range it is good for low speed control. The automatic lockers are a great bonus feature.

Runner up would be quadratracII. It is the same transfer case as quadradriveII but without the automatic lockers.
 
#5 ·
MrMischief, I think you and the OP are comparing different uses. Offroad, no doubt that the Rocktrak system is the best. That's because torque and predictability are what you need most. Lock it in 4-low, lock front AND rear differentials, and the Rubicon will go over just about anything.

But for snowing conditions on-road, and then driving it around as a daily driver... I'd agree that the FD2 is actually better. Although, I think it could be improved by getting rid of the CVT and putting in a normal automatic. Something with a wider range of gears. A lower low, and a higher high.



just my 0.02
 
Discussion starter · #6 ·
Yeah I agree UA. Just imagine if they had a wrangler with the same gear ratio but fd2? Best of both worlds? It would probably get better mpgs and handling on road. Even off road, I think the break locks match up pretty well to RockTrack, but nothing really beats the locked differentials. FD2 is nice though that you don't have to worry about wheel hop.

Im not a big fan of the quadradrive and quadratracks, in 2wd mode they just send all the power to the back or a combo of the both. If I want 2wd its best to have it just in the front wheels.

So basically fd2 loses out because of its low gear ratio isn't quite low enough but if they switched it out and had a transfer case and manual transition like wrangler I think it would be the best offroading/onroading 4wheel drive system. Of course they would have to upgrade the strength of some of the parts but just the way fd2 works is awesome.

The reason I bring up this discussion is I am thinking of getting a wrangler some day... hoping for a more efficient engine and 4wheel drive system though.
 
#7 ·
ColoradoMan said:
... hoping for a more efficient engine and 4wheel drive system though.
Click to expand...
I'm sure if they bolted that Pentastar and a more robust CVT into a Patriot with the FDII system, they could sell ME another one.
 
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#8 ·
All depends on what you want it for. I agree, for on road the Patriot is the best system I ever drove. And it does well off road, with limitations.

If I wanted a true off road vehicle though, I would not choose the Patriot.

It's nice that we have options.
 
#12 ·
UA_who said:
They have that Afmcronnie. It's called a Grand Cherokee.
Click to expand...
Live axles, not a transaxle. No CVT. I prefer a CVT. Also, overpriced by about $10K.
 
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#13 ·
The CVT is great in some situations. Last night I was driving my Tracker through the mountains when we had a white out. There are some big hills on rt 28 where I was, and the road just disappeared ahead, and 20MPH was the best I could do. Going up those hills, in or out of 4x4, when it downshifted, the wheels would break loose for a second, especially without 4x4. The CVT doesn't do this.
 
#14 ·
Afmcronnie said:
Live axles, not a transaxle. No CVT. I prefer a CVT. Also, overpriced by about $10K.
Click to expand...
I'm talking the new GC. It is fully independent suspension. No live axles.

But the programming is similar, and uses BLD to boot. I think there is an optional limited slip diff though too.


As far as being overpriced.... that up for argument. It's much more of a luxury vehicle than the Pat. And so far is selling well, so there must be some value there.
 
#15 ·
The drive system is catered to the customer and the manner the vehicle will be used. In my case, it is unlikely I'll ever take my Patriot off road except to go to a fishing hole. I don't need a Jeep that will climb a mountain. I got over that years ago (or as my wife says, I'm an old fart.) If I really need 4WD I am fortunate to own a Dodge Ram 1500.

I enjoy the utility of a small CUV/SUV with plenty of power to pull my 15 foot fishing boat, but one that also delivers good fuel mileage. My old Cherokee got 14 MPG, sometimes 17 on a good day. But that old Cherokee would snort in the snow.

If ever a vehicle was designed for my own personal needs, the Patriot is it.

Too bad there has to be such a trade off in economy vs off road capability. If fuel economy were better I would probably own a Wrangler.

Unfortunately, we have not had enough snow to try the Patriot out. Just a couple one inch snowfalls. Totally the opposite of last year where we had snow on the ground from late November to mid February.

Since we only live a 45 minute drive from Indianapolis I'm hoping for no snow until after the Superbowl next weekend. Then it can snow all it wants. Go Giants!!!
 
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#16 ·
My test is, can it get up my driveway in winter. I would welcome anyone with a new GC to bring it up, and see what it will do. If I hit the lottery, I might buy one myself and then I will be able to give a better evaluation, and comparison.
 
Discussion starter · #17 ·
My friend and i went offroading with my pat and his grand... Yeah his grand definetly sucked it up, it couldn't even do the easy stuff. It is a last generation grand with 4 wheel drive... not sure what kind but its not trail rated.
 
#18 ·
The base 4WD versions of the GC don't have a transfer case. Without that, I'd take a FDII over it for sure. But if you want to compare the best equipped GC (new version) with the best equipped Patriot, I'd bet the GC would have an advantage off-road.
Not sure on-road in snowing conditions. Probably fairly similar.
 
#19 ·
I told the one dealer I talked to first about the Patriot, that if he got it up my driveway I would buy it. Was pretty bad then and I was using chains, but if I were the salesman I would have brought one up my hill, even if I had to use chains.

I would love to see what a GC would do. Even though I really do need the MPG of the Patriot. Who knows, I might hit the lottery one day.
 
#20 ·
I"ve played around lots with the 4wd system on the patriot and have made a couple videos too. I agree with dixiedawg that for an on road system in the snow and ice the FDI and FDII are probably the best awd systems you can get (biased of course).


I"m currently in a rental 2011 Grand Cherokee. It's a Laredo X with a Hemi. It does not have the select terrain system, but quadra trac1. Full time 4wd nothing to lock it in. From driving it around in town and up some icey hills, it feels very close to my compass FDII. You can turn esp full off and just have the bld's activate. They (BLD's) are not as agressive as on a FDII pat, but if you put decent tires on a QDI GC you would be able to go through quite a bit.
 
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