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IMO it's not worth it, as the current open diff system, directing power by using brakes, works well.
The brake limited differential (BFD) is a virtual LSD, the brakes keep wheels at nearly the same speed just like the clutch packs in a LSD does, and it only does it when needed.

There's a half dozen reason why a true LSD or Locker would provide better performance, but like you said, it works well.

And I have to agree, trying to engineer your own retrofit of the ELSD would take a lot of time, expense and frustration. Meanwhile you've got a virtual LSD, perhaps not as good but still good.
What was wrong with the mechanical limited slip differentials that made them want to replace them with this complicated mess?
Noise and roughness during normal driving, more maintenance, wheels breaking traction in lower traction condition, which an inexperienced driver could lose control. Serviced improperly those characteristic could be worse.

They perform better, but they do have drawbacks, so they come up with different answers that have their own sets of drawbacks....
 

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At the moment this is the only option that I can find for us non ELSD guys for getting a rear locker as no company that I can find makes a diff lock for WK2's yet.
It's unlikely there will every be an aftermarket locker for this platform at this point. It'e been in production since mid-2010 when the MY11 was introduced and this is almost 2019. Limited demand combined with however things are already engineered probably has contributed to that. And Mongo is correct that the electronic setup that uses braking is pretty darn good...maybe not as good as a true locker, but if that's really important, perhaps a different (or older) vehicle is a better choice. That's, of course, a subjective opinion and worth about as much as the ones and zeros it's printed on. :)
 

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The old 3rd party live axles (Dana) and even Chrysler's Corporate Axles, were used across many different vehicles and manufacturers. With changes in axle ratios and differential types, etc over all those applications. Meaning there were already alternatives designed and sitting on the shelf, ring and pinions for different axle ratios and differentials with lockers or LSD.

Not to mention, if an aftermarket company designed a better alternative they could market thousands for all different brands and models.

The WK2 came up with all new differentials, that none of the parts from the past jeeps would work on. And only the WK2 has those differentials. Heck, I "think" the front differential is Mercedes (please correct me if I'm wrong).

So, not only are there no designs and parts sitting on the shelf from some other version of the differential, any aftermarket parts a company would come up with would be limited to the WK2 and that's it. So a big investment in design with very little pay off for a small market to sell to. That's why you're not seeing aftermarket differentials and alternate ratios for the WK2. Past Jeeps it was easy, very little investment for a big market to sell to. Today's WK2, its hard, a lot of investment for a small market to sell to.
 

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The WK2 came up with all new differentials, that none of the parts from the past jeeps would work on. And only the WK2 has those differentials. Heck, I "think" the front differential is Mercedes (please correct me if I'm wrong).
I would also bet the rear diff is from the Benz as well. From a quick google it appears the W164 also gets an eLSD (maybe not in the US market but the US market also didn't get the air suspension and low range gear box IIRC) which would explain why the WK2 get's the eLSD. It slots into the floor pan/subframe already. And no one out there is re-gearing their ML with 4.88 for 35s like they are for their XJ.

EDIT- some quick google image comparisons between the two diffs show very similar mounting points and cases. I'd venture to say they're at least from the mold.
 

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I would also bet the rear diff is from the Benz as well. From a quick google it appears the W164 also gets an eLSD (maybe not in the US market but the US market also didn't get the air suspension and low range gear box IIRC) which would explain why the WK2 get's the eLSD. It slots into the floor pan/subframe already. And no one out there is re-gearing their ML with 4.88 for 35s like they are for their XJ.

EDIT- some quick google image comparisons between the two diffs show very similar mounting points and cases. I'd venture to say they're at least from the mold.
One of the 4 different differentials for the WK2 is aluminum case, the other 3 are cast iron. The iron cased differentials also just look American in their shape and design.

The front differential looks European in its shape and design. I thought I read somewhere its Mercedes, but I can't remember well enough to be confident in that, I could be very wrong.

That all means absolutely nothing, just because it looks close to what I've seen of typical equipment from a country in the past, really is not proof.

And Jeep has had more than one aluminum case differentials in the past, the previous Grand Cherokees had Aluminum rear live axles, at least the differential pumpkin was aluminum with pressed in steel tubes, and they did have problems with it.

The WK2 and Mercedes EL350? were co-designed, that could account for mounting positions being the same or similar to what you see on european vehicles. Or all the rear diffs could be Mercedes, I just don't know.
 

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Ok, then why when i enable just about anything other then AUTO, the off road screen in my '18 TrailHawk indicates that the rear diff. is locked?
Is it a true lock or a phony baloney fib to mislead the masses?

These 4 wheel drive systems in some of these late model Jeeps is getting curioser and curioser.
 

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Ok, then why when i enable just about anything other then AUTO, the off road screen in my '18 TrailHawk indicates that the rear diff. is locked?
Is it a true lock or a phony baloney fib to mislead the masses?

These 4 wheel drive systems in some of these late model Jeeps is getting curioser and curioser.
The ELSD has a clutch pack that it can adjust the pressure on the clutch pack. So it can put enough pressure on the clutch pack to lock it. So its a true lock.

Earlier LSD and Lockers, that did not have electronic control, often had a simple single mode of operation, or could only be switched to a 2nd mode of operation with a switch. i.e. a LSD limited slip but still allowed slip, so better than an open diff that didn't limit slip at all but not as good as a locker that allowed no slip. The pressure on the clutch pack was set by springs and couldn't be adjusted.

The ELSD, a computer is changing the pressure on the clutch pack as necessary, from an open differential, LSD with just light pressure on the clutch pack, an LSD with a lot of pressure on the clutch pack, to enough pressure on the clutch pack that the diff is locked.
 

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I'm under the impression the WK has a Dana 44 Rear Axle. This is one of the most common axles ever put under a light truck and there are several locker options for it.

I have had lockers in these axles on my ZJs, and my WJ I used to own.

Am I wrong?
 

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The ELSD has a clutch pack that it can adjust the pressure on the clutch pack. So it can put enough pressure on the clutch pack to lock it. So its a true lock.

Earlier LSD and Lockers, that did not have electronic control, often had a simple single mode of operation, or could only be switched to a 2nd mode of operation with a switch. i.e. a LSD limited slip but still allowed slip, so better than an open diff that didn't limit slip at all but not as good as a locker that allowed no slip. The pressure on the clutch pack was set by springs and couldn't be adjusted.

The ELSD, a computer is changing the pressure on the clutch pack as necessary, from an open differential, LSD with just light pressure on the clutch pack, an LSD with a lot of pressure on the clutch pack, to enough pressure on the clutch pack that the diff is locked.
So unlike an old school LSD as in my XJ which has a fixed clutch pack pressure to allow slippage during turns, my GC differential has a variable pressure clutch pack controlled by the PCM or some other control module.

Are both rear wheels locked only when the vehicle is driving straight as the Off Road screen indicates?

Next time off road, gonna bring up the off road screen, put it in one of the off road settings and and make some turns to see if the screen still indicates 'Locked' or something else.
 

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I'm under the impression the WK has a Dana 44 Rear Axle. This is one of the most common axles ever put under a light truck and there are several locker options for it.

I have had lockers in these axles on my ZJs, and my WJ I used to own.

Am I wrong?
You might want to post this question over in the "WK" forum area as things are different than with the "WK2" platform. Technically, the current platform is also "WK" because Jeep "forgot" to change it when the current platform came into being, but they are different vehicles. The current version shares a platform with the Merc ML350 series and is metric, AFAIK. And as stated, there are no third party "lockers" available that anyone has found. Given this platform debuted in late 2010 and there's still nothing out there, I doubt there ever will be, either.
 

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So unlike an old school LSD as in my XJ which has a fixed clutch pack pressure to allow slippage during turns, my GC differential has a variable pressure clutch pack controlled by the PCM or some other control module.

Are both rear wheels locked only when the vehicle is driving straight as the Off Road screen indicates?

Next time off road, gonna bring up the off road screen, put it in one of the off road settings and and make some turns to see if the screen still indicates 'Locked' or something else.
If you have QuadraDrive II, which if you have a rear ELSD, you have it. If you QTI or QTII, you do not have a rear ELSD. But you have Brake Traction will use the ABS at individual wheels to limit slip on an axle, thus you have a virtual LSD.

I'm not positive the ELSD releases all pressure for a pure open diff. Because some folks have complained of binding and chirping from the diff at slow full turned steering wheel turning. Which fresh diff fluid solves that problem, degraded fluid lets the clutch pack not slip as smoothly as it should. So perhaps an ELSD doesn't let off all pressure, but it certainly reduces to allow smooth driving even in bad weather on the road.

I'm under the impression the WK has a Dana 44 Rear Axle. This is one of the most common axles ever put under a light truck and there are several locker options for it.

I have had lockers in these axles on my ZJs, and my WJ I used to own.

Am I wrong?
I had an XK (it's the same mechanically as the WK), it was a corporate axle and front diff. I forget the size, but IIRC it was metric, which doesn't change squat for an axle or diff, you just convert the measurements.

The WK also had a lack of alternate ring and pinion sets and locker diffs, like the WK2. I had one or two options, because of the corporate axle, while the WK2 has none, because it has totally different differentials from the WK. But even the WK had nowhere near the earlier ZJ's.

There is WK forum on this site you can ask about it, or go to the WKJeeps website that has tons of technical info.
 

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I would like to know if there is at least one jeep grand cherokee wk2 with a aftermaket rearlocker in the world.

May be somebody can give us some information.

I think ARB has a rear locker for the Wk2.


Thanks
4xd Australia
I would like to know if there is at least one jeep grand cherokee wk2 with a aftermaket rearlocker in the world.

May be somebody can give us some information.

I think ARB has a rear locker for the Wk2.


Thanks
4wdsystems.com.au
They will be making a locker for the rear within the next 6 months, it is a Lokka differential
 

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