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LuckRider 02-25-2011 08:12 PM

WK2 FAQ and Basic Info Compilation
Welcome to's WK2 Technical Section! This is the place for 2011 to current model Jeep Grand Cherokees.

This introduction is designed to help you get familiar with the ins and outs of your Jeep, show you the ropes for this forum, and hopefully answer some basic questions.

This place is THE place to find out about your WK2. Whether troubleshooting, upgrading, or learning about how your Jeep works, you'll get plenty of insight here. The following is a sort of "How to..." for the forum. It is broken down into sections and includes links to threads that cover some of the more common information.

Forum Basics

Your Profile- All registered accounts come with a profile page. Your profile lets you tell a little about yourself, but more importantly, about your Jeep. A completed profile will help other members know what hardware you are dealing with when attempting to solve any problems you post.

Not sure what equipment came on your Jeep from the factory? Request a Build Sheet, it's FREE.

SEARCH Function- I cannot stress enough how important it is to SEARCH this forum for answers before starting a new thread. This forum will be around for a long time and countless topics have been/will be discussed multiple times. If you do not find what you're looking for after running a search, change your wording and search again, and again, and again. Google is a great tool as well.
-Here is a detailed tutorial on getting the best possible results from your search.

The "Dead Horses"- "Don't beat a dead horse." Many topics on this forum are considered dead horses that the majority of members are tired of discussing. This is not currently a problem, but these topics tend to clutter Page 1 of forums and can cause more serious threads to be overlooked. They also waste storage space, which slows down the forum and hassles the webmasters. Every one of these topics can be answered by way of the SEARCH function.

If you do "Beat a Dead Horse" by starting a new thread, take cover. Which brings us to the next point...

Don't Banter- You may get an answer you didn't want to hear, or a comment that you felt was offensive. As Chris Rock would say: "Let it slide"
There are forum guru's and all around helpful guys, just take criticism with a grain of salt. No need to be quick to defend yourself or attempt to insult the poster. Honestly, they don't really care.
This thread is the perfect example of what NOT to do: Best/cost efficient way to gain HP and gas mileage
Additional Information: Rules and Guidelines

-Here is a list of common Acronyms and Abreviations used in the Technical section. This guide doesn't apply that much yet to this forum, but as time goes on, unique acronyms that apply to WK2s will come out of the woodwork.

Show us your rig!
Want to show off your brand spankin' new mod or new purchase? Do it here:

Product Reviews by Forum members: This section is a community effort where members can add a review for any product they have purchased or give a quick review of any product already listed. This gives members a chance to help fellow Jeepers out by warning others what products are a waste of money, or finding products that exceed expectaions -

General Offroading: This thread list, compiled by Unlimited04, covers tips and techniques for all kinds of terrain. Offroad Tips and Techniques

Useful/Informative Threads

This is a start of useful threads containing write-ups or various bits of information on how various components work.

Technical Information:

MDS Information/History:

WK2 4x4 How it Works:

Y2014 Headlights:

Load Leveling Shocks:

Not So Technical, but Still Useful:

Easter Eggs... Cool features not everyone knows:


This only covering information for the 3.6L Pentastar and 5.7L Hemi, the Diesel is to come.

Oil Changes

The WK2 has an oil change indicator system. This system displays a “Oil Change Required” or “Oil Change” message at appropriate intervals on the instrument cluster. The Oil Change Indicator system uses the Powertrain Control Module to process a variety of inputs and then decides on an oil change interval. The factors which point toward severe use include the following:

* Ambient temperature inputs which indicate extended periods of low temperature operation
* Average vehicle speeds which indicate stop-and-go driving
* Run time which indicates prolonged idling
* Trip lengths and coolant temperatures which indicate short trips
* Engine RPM and engine loads which indicate trailer tow usage
* Fuel indications of an ethanol percentage of 60 percent or greater

The oil change indicator can be reset using the following steps:

1. Turn the ignition key to ON but do not start the engine. If you have the push button start, press the button twice with the key in the vehicle and your foot OFF the brake.
2. Slowly depress the accelerator to the floor and release it three times within 10 seconds.
3. Turn the ignition key to the OFF position (or press the push button to turn OFF).

Repeat the process if the indicator does not reset.

Please note, the oil must be changed either when the indicator message appears or when the maintenance interval occurs (whichever occurs first).

3.6L V6 Pentastar:

Capacity: 6 Quarts (with Filter)
Type: 5W-30 API Certified
Oil Pan Torque Spec: 25 ft. lbs./34 N·m
Change Interval (depends on year): Highway Use - 8,000 to 10,000 miles 6tor 12 mo. Severe Use - 4,000 miles 3 mo.

5.7L V8 Hemi

Capacity: 7 Quarts (with Filter)
Type: 5W-20 API Certified (Note: It is important to use only 5W-20 oil for proper operation of the Multiple Displacement System. Use of other weight oils will affect the on/off timing window of the MDS system and may also result in unbalanced engine wear).
Oil Pan Torque Spec: 20 ft. lbs./27 N·m
Change Interval (depends on year): Highway Use - 8,000 to 10,000 miles 6 to 12 mo. Severe Use - 4,000 miles 3 mo.

Transfer Cases 4WD and AWD only

Service for the transfer cases is an inspection. The fluid is considered lifetime and should only be replaced when necessary. The listed interval is when the fluid should be inspected.

MP3010 Quadra-Trac I

Capacity: .51 Liters (1 Pint)
Type: ATF approved to MB 236.10, MB 236.12, such as Shell ATF 3403*
Drain Fill Plug: Unknown Torque Spec
Interval: Inspect 30,000 miles 36 mo.

MP3023 Select-Trac 2

Capacity: 1.90L (4 Pints)*
Type: ATF +4
Drain Fill Plug: 15-25 ft.-Lbs
Interval: Inspect 30,000 miles 36 mo.
*Fill to bottom edge of the fill plug hole.

2011-2013 Transmissions

Note: Do not use additives in your transmission fluid. Claims made by these manufacturers have not been supported to the satisfaction of Chrysler and could jeopardize the integrity of seals.

W5A580 (3.6L Pentastar)

Capacity: Service - 4-6 Quarts. Overhaul - 9.5-10 Quarts.
Type: ATF +4
Interval: Highway - 100,000 miles Severe - 60,000 miles

545RFE (5.7L Hemi)

Capacity: Service - 2WD 5.5 Quarts 4WD 6.5 Quarts. Overhaul - 14 Quarts
Type: ATF +4
Interval: Highway - 100,000 miles Severe - 60,000 miles

Air Filter

Note: High flow filters do allow more air for the engine, but they also provide less protection This higher flow comes at the cost of protection because they allow larger dust particles in the engine.

3.6L Pentastar

Filter: MoparŪ p/n 4861756AA
Interval: Highway - 32,000 miles 24 mo. Severe/Dusty - 16,000 miles 12 mo.

5.7L Hemi

Filter: MoparŪ p/n 5018777AB
Interval: Highway - 32,000 miles 24 mo. Severe/Dusty - 16,000 miles 12 mo.

Spark Plugs

Note: The 3.6L Pentastar is Chrysler's first engine to use 12mm Spark Plugs. Over-torquing them can cause improper heat transfer which can induce pre-ignition. This pre-ignition can cause engine damage. The 5.7L Hemi uses a torque critical tapered design. Do not over-tighten these either.

3.6L Pentastar

Plug Count: 6
Gap: .040
Torque: 13 ft. lbs.
Type: MoparŪ p/n SP149125AD (Champion R8ZWYCB4)
Interval: 96,000 Miles

5.7L Hemi

Plug Count: 16
Gap: .040
Torque: 13 ft. lbs.
Type: MoparŪ p/n SLZFR5C11 (NGK ZFR5C11)
Interval: 30,000 or 100,000 Miles depending on year

Throttle Body Cleaning

The throttle body CANNOT be cleaned. Don not use spray cleaners or apply silicone lubricants to any part of the throttle body. These types of products can damage the throttle body components. The throttle body has no serviceable components and is replaced as an assembly. It should last the life of the vehicle.


3.6L V6 Pentastar

The 3.6L V6 Pentastar engine is designed to run efficiently on 87 octane gasoline. The use of premium fuel is not recommended for use in the 3.6L Pentastar engine, and in some instances can result in decreased performance and economy. I can not confirm the use of E85 in every Pentastar, however, it looks like it is safe for all 3.6L engines. The 3.6-liter V6 engine delivers 290 horsepower (216 kW) at 6,350 rpm and 260 lb.-ft. (353 N•m) of torque at 4,300 rpm, an increase of 38 percent in horsepower and 11 percent in torque over its predecessor, while providing customers up to an 11 percent improvement in fuel economy. The Pentastar V-6 is designed to run on regular gasoline, offering a 10 percent reduction in fuel cost compared with premium fueled engines. The engine’s torque exceeds 90 percent of its peak value from 1,600 to 6,400 rpm, which provides customers with outstanding drive-ability and responsiveness. Power Graph:

5.7L Hemi

The 5.7L Hemi is tuned to run most efficiently on 89 octane fuel. While this fuel is recommended, use of 87 octane fuel will not cause damage and can be safely used in the 5.7L Hemi. As with the 3.6L Pentastar, use of premium fuel is not recommended and can result in poorer performance in some instances. Unlike the 3.6L, use of E85 is not acceptable in any case. This fuel can cause damage to the engine and other various components. The all-new 2nd generation 5.7-liter HEMI V-8 Eagle engine offers better fuel economy, improved idle quality and overall refinement, along with more horsepower and torque. HEMI has always been synonymous with power, and now - thanks to VVT, expanded four-cylinder mode in the MDS system, and a host of other technologies - Chrysler's new HEMI delivers more fuel efficiency and refinement, along with even more power. Other enhancements include an increased compression ratio and an active intake manifold with long runners for low-end torque and short runners for high-rpm power. For the 2011 model year, the 5.7L produces increased power and torque over the previous model, delivering 360 horsepower (268 kW) and 390 lb.-ft. of torque (520 N•m) @ 4,250 rpm and features Variable-valve Timing (VVT) and fuel-saving MDS technology with dual exhaust to maximize efficiency.

This thread will be update as more information becomes available.

Edit: Last updated by ColdCase 5/7/2014

Chrazy-Chris 04-26-2012 09:55 AM


Originally Posted by Alaska-HWY JK (Post 13089997)
Is there any chance of adding which tire sizes fit to this? Thanks.

+1! here is a thread on tire sizes:

I'm looking forward to the aftermarket section: Lifts, rock sliders, floor mats, CAIs/Filters, roof racks.... a lot, I know. Maybe it should be it's own sticky thread?

To help, here is a decent thread started on floor mats:

Much appreciated!

ColdCase 12-12-2013 09:38 AM

Traction Control, BTC and ELSD
The marketeers have a tendency to confuse things.

All WK2s come equipped with Brake Traction Control (BTC). The traction control computer senses wheel spin and applies brakes to the spinning wheel. Jeep also offers, on some models, an optional Electronic Limited Slip Differential (ELSD) that replaces BTC on the rear axle (BTC is still used on the front 4x4s regardless). The ELSD diff has an electric motor driven clutch within the diff that locks the two axle haves together from 0 to 100% under command of the traction computer. This is similar to what happens within the QTII transfer case.

Older limited slip differentials used an hydraulic pump powered by the differences in L/R axle spin to generate the forces to clamp the clutch. You needed some wheel spin to power the locking mechanism. And, given the less sophisticated and slower traction control of the day, it made sense to put them on both axles. With ELSD, the traction computer can lock the diff regardless and in anticipation of wheel spin. ... such as when you stomp on the throttle or are starting off in snow mode. ELSD in the rear combined with higher performance traction control computers makes front axle ELSD of little benefit. There is benefit to diff locks/limited slips for off road situation where you want to spin the tires to dig down to traction and throw off lug plugging mud by spinning the tires. Turning ESC off may help.

Today's BTC is effective too but is hard on brake pads, especially in the more challenging off road environments. BTC is not as efficient as ELSD getting horsepower to the wheel with traction as it converts much horsepower to heat. Given similar tires and driver skill, a BTC WK2 will get you just as far as an ELSD WK2. The ELSD equipped WK2 will get you there with less drama (wheel spin) and require less driver attention to detail, however. ESLD has more advantage in high HP applications, like the SRT, where wheel spin on launch impacts 0-60 times. All current SRTs are equipped with ELSD and launch control.

ELSD is part of the QD option. Any vehicle combination that offers QD will contain the ELSD. QD is not offered on V6 models except 2017 Trail Hawks.

ColdCase 03-01-2014 07:01 AM

Build Sheets

ColdCase 09-29-2014 04:54 PM

195 Rears in some V6s
Note that Jeep has been installing 195mm rears in some WK2s since 2013. Look for DRH 195MM Rear Axle in your build sheets.

ColdCase 04-25-2015 02:57 PM

Automatic Settings and the Air Suspension.
•Auto - When in 4WD High range the vehicle height is at NRH. The vehicle systems are set to normal performance settings. Combines optimal traction with seamless steering feel. When in 4WD Low range the vehicle height adjusts to 38 mm (1.49 in.) above NRH, the transfer case locks, and the transmission shifting adjusts to off road shifting.

•Sport - When in 4WD High range the vehicle height adjusts to 15 mm (0.59 in.) below NRH. Electronic Stability Control (ESC) and traction control tuning thresholds are raised, and the Antilock Brake Control (ABS) allows less wheel slip, all to allow more driver control. Also the transmission shifting adjusts to a higher performance shifting. Not available in 4WD Low range.

•Snow - When in 4WD High range the vehicle height is at NRH. Traction control is adjusted to allow less wheel slip, and initial vehicle launch will be in second gear. When in 4WD Low range the vehicle height adjusts to 33 mm (1.3 in.) above NRH, the transfer case locks, the transmission shifting and ABS adjusts to off road settings.

•Sand/Mud - When in 4WD High range the vehicle height adjusts to 38 mm (1.49 in.) above NRH. Electronic Stability Control (ESC) tuning threshold is raised, and the ABS allows less wheel slip to allow more driver control. When in 4WD Low range the vehicle height adjusts to 38 mm (1.49 in.) above NRH. The transfer case and the Electronic Limited Slip Differential (ELSD) locks, the transmission shifting and ABS adjusts to off road settings.

•Rock - Not available in 4WD High range. When in 4WD Low range the vehicle height adjusts to 65 mm (2.6 in.) above NRH. The transfer case and the ELSD locks, the transmission shifting and ABS adjusts to off road settings, and hill descent control is activated for steep downhill control.

There are five predetermined manual height settings; Normal Ride Height (NRH), two above and two below NRH. The predetermined vehicle heights (above or below NRH) are as follows:

•Off-Road 2 (OR2), + 65 mm (2.6 in.) (Except if equipped with AMS + 56 mm [2.2 in.])
•Off-Road 1 (OR1), + 33 mm (1.3 in.) (Except if equipped with AMS + 28 mm [1.1 in.])
•Aero Mode, - 15 mm (0.59 in.)
•Park Mode, - 40 mm (1.57 in.)

Note, it appears that OR2 hight starting in the 2015 model year is +2.2 inches

ColdCase 11-05-2015 07:10 PM

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