(Part 3) Top products from r/GrandCherokee

I just got an 08 WK Limited 5.7 with 51k on it. Here is what I did immediately, I have the previous service records and it seems as though some of the work may have been done, it wasn't 100% clear and I just wanted to know a baseline.

Replace PCV Valve (cheap part, just unscrews by hand to replace, super easy), Clean Throttle Body (remove air box, remove throttle body, clean with ONLY isopropol alcohol and a clean rag) and install Billet Technology (or equivalent) Catch Can. This is all done because the PCV system on the Hemi basically sucks, you'll see when you remove the throttle body that it will most likely be gunked up, the PCV lets too much oil through. This is cured with the catch can. Immediately helps throttle response and minor hep to fuel economy.

Replace MAP Sensor. Honestly not really sure why, all the forums say do it, it's a $20 part and basically pop-out, pop-in replacement. A little tricky to get your hand in behind the manifold the get it, takes some maneuvering but be patient, you'll get it. Said to have positive effect on fuel economy.

Replace EGR Valve. This can be tricky as the alternator blocks one of the bolts. Many people will tell you to cut the bolt and install a new shorter one. This seems like a lot of extra work to me. I just removed the belt (easy to do) and unbolted the alternator (2 bolts). This took me all of about 6 minutes to do, then the new EGR (and new gaskets) just bolt back on.

While I had that off I replaced the serpentine belt. Cheap enough, and why the hell not, now I know exactly ow old it is. While you're in there check all your pulleys, tensioner, etc. Make sure they move smoothly and quietly. I forgot this step and I DID have a squeak I wanted to address. I still have said squeak. Next nice day I'm gonna get back in there and check.

Spark plugs. I have an 08, so it wasn't hard. Unbolt each coil, gently crack the plugs with a ratchet (I have a great plug ratchet set I'll link below, get it, it will help with all your plug changes on any deep well hemi). Change your plugs. I got the Champion 57- Copper core generally the recommended plug), dab of dielectric on the end (no anti-size, I don't like it, I change plugs every 30k so I shouldn't need it, some say anti seize leads to accidental over-torque, personal preference I guess). Gap plugs to .44 and torque to 13ft.lbs.

Next I did K&N drop in air filter, swapped my air resonator for a SRT Inlet tube (take off, bought online for $20 shipped, search the STR forums for the for sale items) and extended the drain hole for more air inlet. Sounds great, that throaty cold air intake everyone loves without the risk of slurping up some water and hydro locking. Be sure to perform regular main on the filter, clean and il it as required by the spec.

Oil change. Mobil 1 Synthetic, 5w-20 & Mopar filter. Because oil change....

I also installed the fumoto quick valve to change my oil easier. It scares some people, I looked it over and feel confident that it will not open accidentally, it has a decent spring type safety.

I plan to soon flush and fill tranny, radiator, transfer case & differentials. After that is all done I may swap out a few more sensors. IAT, O2, Crank Position, etc. With all that complete I will feel as confident as I possibly can in the maintenance of my Hemi.

I may point out that i'm not really mechanically inclined. I have just been doing a lot of research on forums (jeepgarage, cherokeesrt8, jeepsunlimited, etc) I founds lots of good write ups, reviews and information. Take you time, do your research and everything will be there.

Generally my truck runs smoother, quieter, more powerful and a little better MPG. It's only been about 100 miles since I did all this, but for the overall $$ I spend (under $400) it was totally worth it. At a dealer my guess is this is like 1500 worth of work. Below are some links. Have fun.



Tune up kit
http://www.amazon.com/GRAND-CHEROKEE-COMMANDER-5-7L-HEMI/dp/B003ZW9EUM

Spark Plug Tool
http://www.amazon.com/KD-Tools-3-Piece-Magnetic-Universal/dp/B000NIEECO

Fumoto Oil valve
http://www.fumotousa.com/parts.php?partname=F106N&partnumber=33

Spark Plug Change Tutorial
http://www.jeepgarage.org/f156/diy-hemi-5-7l-spark-plug-change-50750.html

EGR (I didnt follow exaclt, i just removed alternator, this shows all steps including cutting botl. You choose your own adventure here...)
http://www.jeepsunlimited.com/forums/showthread.php?516169-DIY-how-to-install-a-new-EGR-w-pics&highlight=egr%20valve

PCV Valve
http://www.jeepforum.com/forum/f67/changing-pcv-valve-1336134/

Throttle body cleaning
http://www.jeepforum.com/forum/f67/throttle-body-cleaning-tips-1342502/index2.html

MAP Sensor (start at post #8 in this thread, thats where the good info starts, but feel free to read from beginning if you want)
http://www.jeepforum.com/forum/f67/5-7l-map-sensor-location-1340713/

And for ALL the info on your WK, use this site as your bible.
http://wkjeeps.com/

Hope this helps a bit!!!

Okay, take all this for what it's worth (your mileage may vary, I am not a lawyer, I didn't stay at a Holiday Inn Express last night, yada yada yada).....

I bought an '02 WJ in Feb (to replace my '01 XJ) and had similar issues like you're describing. Based on my experiences with my XJ previously, when it comes to the cooling system I tend towards doing a complete overhaul in one go rather than addressing one component at a time.

For your rig, you've got 4 main components to deal with (in my opinion) when it comes to the cooling system:

• radiator & cap
  
• water pump
  
• thermostat
  
• electric fan and relay/controller
  
  If you've already replaced the fan & relay/controller, you should be able to (mostly) rule that out. If you need to check and see if it's running, physically pop the hood and look. It should also be on full time when you switch the AC on.
  
  You've replaced the waterpump, but you say it's "steaming". From where? Grab a flashlight and see if you can figure out where the steam is coming from. It might simply be that you either didn't torque the bolts down enough and it's leaking under pressure, or the surfaces the gasket sandwiches between weren't cleaned resulting in a poor seal, or a combo of both. If it's visibly coming from anywhere around the gasket, you might need to pull the pump and re-do it with a fresh gasket & gasket sealant. Make sure the surface of the block is scraped clean of all the old gasket material and use a good gasket. I have a low opinion of the ones that come with the water pumps and will spend the $$$ on a Fel-Pro (Fel-Pro 35629 water pump gasket).
  
  Check your coolant for debris, particles, any fines or silts that you can see, etc. If the radiator has never been replaced, odds are good that in the 16 years your WJ has been running the radiator is clogged. If you replace the radiator, a good flush of the cooling system will get rid of most of that junk so you don't end up clogging the new radiator and get a fresh 50/50 mix of coolant in there. Top it off with a new Stant radiator cap while you're at it.
  
  Same deal with the thermostat, it may simply be time to get a new one. Consider getting a new housing & gasket while you're at it. Not necessarily a requirement, but I tend towards replacing the housing when I do the thermostat "just because".
  Stick with the OEM 195° thermostat - I ran my 4.0L XJ with the 180° thermostat during the summer in Vegas (100°+ routinely for months) and it noticeably helped but I went back to the 195° thermostat after summer temps ended. If that's your climate, the 180° thermostat might be good for a while but I don't recommend it as a straight replacement.
  
  Is replacing nearly everything in the cooling system overkill? Maybe so, but I take into consideration my WJ is 16 years old (like yours) and I have no idea what kind of maintenance the previous owner has done. So it may cost a little bit, but it's worth it to me knowing all the main parts to the cooling system are "like new" which should eliminate overheating issues.
  For a little bit of perspective on why I think that way (ie- total overhaul) this is what the thermostat on my '01 XJ looked like when I replaced it a few years ago: https://imgur.com/a/FvZQi9E
  The extra ring looking piece to the right of the thermostat is piece of another thermostat that was inside the block.
  When I replaced the radiator on my WJ, I pried off one of the end tanks the core was clogged like you wouldn't believe.
  
  Once you've gone through all that, you also have the option of installing a mechanical clutch fan. This thread on JeepForum gives some good info and links. The tl;dr for that is to go grab this Hayden 2787 fan clutch and this Dorman 620-602 fan and spin it onto the threaded nose on the water pump.
  
  I've got the Torque app with a bluetooth OBD-II scanner so I can check the real numbers vs what the dash gauges are showing. Trust me, you can be running hot before the temp gauge starts to creep past the halfway mark.
  
  After replacing all the bits & pieces I talked about above, and installing a mechanical clutch fan, my WJ is running cold. Yesterday was high 90s here in Vegas, and idling in a parking lot w/ the AC on the temp never broke 200°. Creeping through traffic on the freeway w/ AC on hit 206°-210° but didn't get higher. Driving about 75-80mph for a while, and it was in the 190°-195° range.
  These are the same temps I was seeing with my XJ after I did the cooling system overhaul, so I have no doubt when it starts breaking 100° here in Vegas I won't be seeing any overheating issues with the WJ.
  
  

Clean looking ZJ! Congrats!

Do you know any of the maintenance history? If not, I would suggest changing all fluids and doing a tune up before doing any upgrades/mods.


Fluids

• The 4.0 seems to love Shell Rotella 10W30 - either T (Conventional) or T6 (synthetic) its up to you and use a quality filter - Wix, NAPA Gold, Mopar, or Motorcraft FL-1A
  
• Drop transmission pan and change fluid and filter - ATF +4 only No additives or anything else. Adjust the bands and TV cable (link below for TV adj.)
  
• Drain and fill the transfer case - Selec-Trac transfer case (NP242) and Command-Trac (NP231) get ATF +4 also. Quardra-drive (NP249) gets a special Mopar fluid
  
• Drain and fill both differentials - if you tow 75W140 full synthetic in rear 75W90 in front, otherwise 75W90 in both
  
• Drain and fill coolant. Zerex-G05 is now the OEM coolant, but you'll be fine with the old school green fluid. Also a good time to look over the condition of the rest of your cooling system. If you're running below 210 you're going to want to put a 195 thermostat in - running to cold causes tons of problems
  
• Siphon out your power steering fluid - either through the high pressure hose, or with a turkey baister. Use only Chrysler approved fluid not ATF. You'll need to burp the system after by turning your wheels lock to lock several times and topping of the fluid
  
• Bleed your brakes! These brake lines are prone to rust already, and brake fluid absorbs water from the atmosphere over time and they will rust from the inside out. spray the bleeder screws with PB Blaster a couple times a day for a few days before you get started to free them up - Check your pads, shoes, drums, and rotors too!
  
  
  Tune Up - This is what I'm currently running in my 4.0
  
  
• Champion copper spark plugs
  
  
  
• Denso wires
  
  
  
• Accel distributor cap with brass contacts
  
  
  
• Accel Brass rotor
  
  
  
• Accel Ignition coil
  
  
  
• Bosch air filter any paper filter is fine though
  
  
  
• gates belt
  
  
  
• Clean the throttle body and IAC
  
  
  
• Adjust the Transmission Throttle Valve Makes a big differnce in shifting
  
  
  
• Clean the Grounds - #1 in the "Dirty Dozen" list below
  
  
  
  If you do all that, and you have any issues with stalling or hesitation from the engine, This should be your bible - The Dirt Dozen
  
  Your ZJ will be running like a top, and ready to lift, modify and most importantly be reliable when you get out there to wheel!
  

Okay, I'll try to get this done on mobile.

Headlights: heat them and pop them open. It's honestly a huge pain in the ass Lol. Mask off and paint the internal bezel to your preference, but at least leave the ribbed and textured parts silver to ensure you still get good beams out of your lights. (The corner turn lens is also in there, see below for the tinting process.) Buy some butyl rubber ribbon and use that to heat and reseal your lights. I'll post links to the process I followed if I can dig them up on my PC. it's a little labor intensive, but the unique look is worth it.

Taillights and front corner turn signals: follow the process for applying VHT Nightshade spray on tint. I think mine are 3 or 4 coats and then clear coat. The clear reverse lights were masked for the tint and unmasked for the clear. You can then sand and buff them to whatever level of gloss you want. Mine were left slightly matted.

Lift/shocks/wheels/tires: it's an RC 2" bb with load levelers I got from Kolak on Jeep forums. Wheels are Discount tire MB TKOs and tires are 265/70R17 Goodyear Duratracs.

It's got a pinchweld mod to clear the tires.

If you want deeper info say the word and I'll give you a deeper write up when I'm on a PC.

EDIT for links

Sorry it took me 2 days to see this post- Bad Mod.. bad!

One of my personal favorite can-do-in-stock-form-and-still-challenge-yourself trails (also a bit of proving grounds for any new mods I do as it is so close to Denver- Yankee Hill Road

I would also pick up a copy of this book for future reference.. This one has a lot to do with trails in Southern/ Central CO- but there is a version 2 of it that has trails that are a bit more northern.
I have used these books religiously since highschool for leading trails around CO, and even Moab. It is a great resource. For everything else- there is Traildamage.com- You can use the map to drill into trails closest to you or where you are looking to go out and the descriptions are pretty good most of the time (i.e. written by users... so think of Yelp reviews.)

Finally, It is a bit late for me this weekend, and I am travelling next weekend, but if I remember I will hit you up next time I am headed out/ up- would be happy to show you around.

Replace the tie rod ends. You need penetrating oil, a pair of big pipe wrenches, and some strength to get the ends off.

The steering stabilizer looks like it's shot. It's 2 bolts to remove; super easy. With that leak I'll bet you can easily compress it by hand. A new steering stabilizer is cheap and worth the money[1].

If you plan on lifting the Jeep in the future, get an adjustable track bar[2]. Also super easy to replace

Go for an alignment after you do this, particularly if you don't tape the threads on the old tie rod ends to act as a guide for how far to thread the new ones in.

I have no idea how many miles you have on your jeep, but I'll just give some perspective:

• at 65k I had to replace all my shocks. Had to. They were all shot.
  
• at 90k I put a 3" lift on. Steering stabilizer, track bar, shocks, front end links, and OME springs went in the front. This made my suspension and steering amazingly tight.
  
• at 120k I replaced tie rod ends. Had to.
  
  If you're over 100k and everything looks stock, I highly recommend throwing $1k at the suspension. Even if your'e not going to lift it, replacing everything will make a HUGE difference.
  
  Oh, and sign up for a couple forums. This sub is nice, but forums are much better wealths of knowledge.
  
  [1] http://www.amazon.com/Rancho-RS5409-RS5000-Steering-Stabilizer/dp/B000CB42EM
  
  [2] http://jksmfg.com/i-8952506-grand-cherokee-wj-1999-2004-adjustable-front-trackbar.html
  
  

I have fought the headlights on the wife's 02 for a while now and tried several cleaners and abrasive kits. The issue I have was keeping them looking clear afterwards. Interesting enough I cleaned them up with Rain X Glass Cleaner and after a couple weeks they still look good.

Thanks! Is it one like this? https://www.amazon.com/70268-SuperCooler-Automatic-Transmission-Cooler/dp/B000CIGE9G/ref=sr_1_1

Felpro makes a really great replacement gasket that’s reusable and never leaks. The 4.0 has a ccv rather than a pcv system and I always replace both vents and grommets (and the little tube connecting the rear vent) along with the gasket when I get another Jeep (I have 6 right now).
Rear crankcase orifice vent is dorman# 47057: https://www.amazon.com/dp/B000JZI1U2/ref=cm_sw_r_cp_api_o1AQBb8PJSXPA

Grommets are both dorman# 42344: https://www.amazon.com/dp/B06XS8XYHJ/ref=cm_sw_r_cp_api_K2AQBbMPJ1Z33

The front vent is available in different heights depending on year/model but I think yours is a doorman 47079. In a pinch you can always buy 2 of the orifice ones and drill out the restrictor.

>I have a good knowledge of car maintenance but have never owned a 4wd before.

>
I have a 1994 Jeep Grand Cherokee 5.2V8, NP249J transfer case, Dana30 front diff, and ?Dana44A rear diff? still not 100% sure about the rear diff model


1994 would have a d35


>
If I use this Lucas gear oil 75w-140 Synth, which says excellent for limited slip use, do I still need to add this additive when I service the differentials?


That'll be fine, no need for an additive.

>
Also ATF+4 in the transfer case?


Dex/merc or atf+4. The tcase isn't picky.

>
How do I tell if my Viscous coupler is bad? Recommendations if it is?


I think the test is to turn in a tight circle and if you feel binding it's bad. Recommend a 231 or 242 swap.

This is what I used.

Quick fist it!

Here you go

I went cheap but it turned out decent.

Yeah I was having trouble finding anything without ac. A few forums I found said this belt works, so I guess I will just have to try it.


https://www.amazon.ca/Dayco-5070825-Serpentine-Belt/dp/B000Q0LWAG