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Discussion Starter #1
So, after reading the manual, I'm still not sure. My 2018 compass 4x4 is front wheel drive or all wheel drive? Also, when I rotate my selector switch to select snow mode,
does the vehicle have to be in neutral or stationary? Lastly is there a speed limitation when I push the selector switch in to select four wheel drive.Thanks all.
 

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This is kind of a grey area. The Compass automatically engages the 4x4 system at take off and low speeds. Because of this, it can be considered AWD. But, it also allows the user to manually engage/lock the system, which is similar to how 4WD works. Some will say since we don't have a true transfer case, it can't be 4WD. Personally, I wouldn't think too much into it. It has 4WD automatically when the vehicle detects that you need it. Or you can manually engage it. As for engaging/locking it, you don't have to be in neutral, but a slower speed is recommended. The speeds should be in the manual, but it was like under 5MPH or something for engaging, and can be used up to like 40MPH. For changing modes, it's just altering the programming in the system, so once it's engaged, you should be able to change modes on the fly.
 

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Here is a PDF of the owners manual it will answer your question.
 

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Discussion Starter #4
One more thing. So if the vehicle starts off in four wheel drive up to a certain speed, what does it switch to? Front wheel drive or rear wheel drive?
 

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My understanding as always been "always on all-wheel drive with a bias toward the front", locking 4x4 means a bias to all 4 wheels instead, but its still all-wheel drive so will adjust as it thinks is needed. The different modes you can choose change the bias and the reaction template based on what you select so it can route power to the wheels more effectively based on what it expects instead of figuring it out on the fly in "auto" 4x4 mode.

It's 4WD practically... but in reality its an intelligent all wheel drive that ACTS like 4x4 most of the time.
 

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RadRacer said:
Some will say since we don't have a true transfer case, it can't be [true] 4WD.
It is a part-time AWD setup, and a very watery one at that. Sufficient for snow and bad weather but not any better than a Subaru, maybe not even as good as a Subaru really. It cannot gracefully direct the power wheel to wheel, it can do some brake modulation voodoo that kinda helps but it doesn't have torque-vectoring or anything nice like that.

The power take-off can disconnect at the front to save gas and using the 4x4 lock button simply prevents that from disconnecting. In the rear diff a variable clutch can leave the propshaft and some of the differential guts disengaged for further gas savings due to less rotating parts.

Due to the way the power take-off works (after the front diff, off the passenger-side axle) your power to Front Right, Rear Right, and Rear Left wheels are entirely dependent on whats happening at the front left wheel. The other three wheels get power equal to half the traction (or brake capacity) at the front left tire. Basically if your front left tire looses traction you are in trouble, it can't really get power to the back other than half of what it can brake at the front left.

The weaker your brakes get the less the brake modulation voodoo is effective, and since it has literally no other tricks up its sleeve that are helpful traction-wise, its safe to say its a pretty weak barebones AWD. Still better than FWD but a true 4x4, it is not. All its AWD party tricks are dedicated to fuel savings and handling improvements.

RadRacer said:
As for engaging/locking it, you don't have to be in neutral, but a slower speed is recommended. The speeds should be in the manual, but it was like under 5MPH or something for engaging, and can be used up to like 40MPH.
You can engage the AWD at any time, at any speed, and drive it "locked" at any speed. All it does is feather in the clutch in the RDM until the propshaft and everything is spinning the same speed then it locks in the dog clutch in the PTU. The only time it can't engage on-demand is if you have the front wheels spinning excessively and the car is not actually traveling forward to roll the rear tires, and it basically won't let you get into that situation since it seems to start from all stops with the PTU engaged.

EROTKU said:
My understanding as always been "always on all-wheel drive with a bias toward the front"
Well, its a FWD car with a power take-off option to the rear wheels to achieve AWD so its definitely "biased toward the front". Like I said above the PTU is not a part of the transmission its an add-on that comes after power has already flown through the front diff, so its incapable of sending anything to the back wheels independently, the back wheels share the power being sent to the right front wheel.

Its not "always on all-wheel drive", it will disconnect the propshaft to the rear wheels on the highway unless you have the lock button on. It does reconnect the propshaft in the front once you slow down from highway speed but it may not be engaging the clutch in the RDM much so its just kinda floating "ready" to engage the rear wheels but in most cases it won't or it will just be a tiny bit like 10%.

The programming on the whole thing is really clever and complicated but the actual mechanical implementation is that of an extremely limited system compared to a traditional 4x4 truck with transfer case. Hence it is in no way a "true 4x4".

For a Chrysler-branded crossover SUV this would be fine, I'd still drive one and I'd still love it, but to me it is not a system worthy of the "Jeep" name.
 

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For a Chrysler-branded crossover SUV this would be fine, I'd still drive one and I'd still love it, but to me it is not a system worthy of the "Jeep" name.
Very true. And an excellent review of the Compass AWD system.

Frankly with good tires FWD will get you anywhere this AWD system will. If you get seriously stuck with either system you'll be waiting for a hook. A Compass will not crawl out of a drift like a Wrangler. If you drive a Compass like its only FWD you'll probably be OK and the AWD will give you a slight, very slight, advantage.

The "Jeep" name is a good seller so they stick this AWD system on a vehicle that should have been branded something else and figure most people aren't venturing into much more than highway snow or a suburban street. For the most part they're right.

I think Fiat is making a mistake putting the Jeep label on something that is only marginally better than FWD. The only Jeep should be a Wrangler or a Gladiator. The Compass and Cherokee should be Dodges and the GC a Chrysler. (They need something to save those brands.)

If they want something more car-like for the Jeep line they should put a bona fide 4wd system in the Renegade. THAT would sell! In fact, I'd be driving one. Seems companies can only think of bigger these days. Something else I'd love to own would be a Wrangler pick-up like the old Scrambler. As it is I drag a makeshift trailer behind my Patriot.
 
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