Over the last 15 years some common fault patterns have emerged for the '99-'04 WJ Grands. Im posting this as a very liberal assessment based on my own experiences and certainly some of you will have easier or harder solutions so please tell us about your own experiences to help out all the WJ owners - the more info the better. Here are a few of the big dollar items I've found in the last few years:
* Motor Mounts
This affects all V8 WJs. The mounts prematurely wear due to poor material quality from the factory. You probably wont notice a problem unless you visually inspect them close up for cracking. Check them as early as 50K and expect to replace both at the same time as part of normal long term maintenance.
Replacement mounts are @ $200 shipped from the states. If you go to a shop for installation expect to pay $400+ for labor alone.
You can do this at home if you have some basic tools but its a very trying job. You wont need to remove a bunch of extra stuff for access but you will need to loosen a few things and you will need a floorjack. The driver side is the worst to replace due to tight clearances and requires some ingenious thinking and a LOT of patience to access the top two attaching bolts using an open end spanner. The passenger side is pretty straight forward. Dont fool yourself into thinking its gonna be a typical weekend fun job with a couple of buddies and some beer as it can quickly get a lot more complicated than
expected.
Just a note on the driver replacement mount: if you buy an Anchor brand #3008 you may need to overdrill the bottom holes on the mount to make it match up to the block for the attaching the bolts. its no big deal but the poorer grade Jeep mounts cost 4 times as much.
* AC Blend/Vent Door Failure
Poor quality plastic construction of the factory blend doors lead to the stop tabs and hinges to breaking over time. These doors get a lot more use than you know as the doors will automatically calibrate/rotate via software programming in order to fine tune their adjustment. Automatic calibration happens without your input (or knowledge) and occurs every 20 key on/off cycles. The point is they cycle through their movement quite often and the more something is used the more likely it is to fail.
Broken parts result in the blend and/or vent doors sticking in position. The common symptom is too much cold or hot air entering the cabin on either/both the driver or passenger side via the dash and/or footwell outlets. The dealership fix is to remove your dashboard including degassing the AC and draining the cooling system amongst other things. not to mention some unsupervised apprentice will get stuck with the job probably resulting in squeaks, leaks and other issues. expect 2+ trips to the dealership at minimum and a BIG labor bill: $2000+ in labour plus parts and even if you are still under
extended warranty you are going to pay a few hundred in excess (at best). There is a factory technical service bulletin for this issue using upgraded parts but it is not a recall. The dealer is the last place to go in this case.
However, there is a quick fix that is much cheaper and it works very well. A couple of companies in the states produce replacement blend doors using durable alloy parts vs the original factory plastic. Replacement does not require dash removal in most cases but it does involve cutting into the AC/Vent plenum under the dash.
If you have a Dremel cutting tool you can get it done dirt cheap at home for around $210. Its not that hard for the average weekend mechanic and only takes about an hour.
* Radiator Leaks
Its a common problem with all Jeeps but WJs are one of the most expensive to fix. This is because you must remove the front bumper and fascia to access the radiator for removal and its all due to the design of the fan shroud. Even so, the job isnt that hard but most shops quote big dollars for labour as it is certainly a time consuming process. Expect to pay well over $900 at a shop but you can do it at home for less although replacement radiators arent cheap. And dont let a shop tell you the coolant needs to be drained or the AC needs to be degassed at extra expense - its not necessary and you should run away if they try to include this in a quote - its a big clue you are dealing with the wrong shop. A smart shop will get around this if they have any experience with WJs.
* Transmission Shift Issues
These electronically controlled trannys suffer from software program deficiencies as well as failed shift solenoids. Jeep has never come out with a proper fix and although there are heaps of technical service bulletins & software updates they have never issued a recall. Simple maintenance wont cure it but start by making sure your fluid level and fluid type is correct (its crucial). Symptoms are wide ranging but most complaints are hard shifts and/or erratic shifting up and down between gears. There is no real cure and factory support is non existent. There is no way to tell what it could cost and in some cases suggested repairs exceed the price of the car. New trannys are not a guaranteed fix and you are likely to have the same issue so dont go thinking this is the cure although dealerships love selling new trannys. Serious online research and phone calls are suggested before spending any money. If you have warranty (and you probably dont) go to the dealer and
make them sort it but the outcome is a coin toss at best. Best advice is to go slow and be wary at every avenue. Its one of the worst WJ issues you can be confronted with. Sad but true.
* Cam Sensor
The common symptom is engine stalling and it often happens while turning. Its safe to say a bad cam sensor reading will set off engine misfire codes which is also a common problem (see below). Check your computer codes first and if any pertain to this sensor or misfires then replace the cam sensor first. Be aware this sensor wont always set a code if it fails but its a common issue that is cheap and quick to replace (read that as "you are probably going to do at some point anyway") so get it done with now as a base starting point and make it a mandatory long term routine replacement item.
You can do this at home cheaply and quickly and it requires no special tools. Plan to spend $70 for a decent aftermarket brand sensor.
* Misfire Codes
Dealers love to replace or swap coil packs to address misfire codes but i cant say ive ever really seen this as an effective solution and Jeep doesnt have a definitive fix for misfire codes. Ive never seen a single bad coil pack on any Jeep (but thats not to say it doesnt happen) but dealers will usually start with swapping coil packs around chasing this problem as its a quick profit procedure for them and usually results in more diagnosis time coming out of your pocket. I have to be fair as an experienced dealer tech: this is one of the hardest issues to diagnose from the perspective of the technician and because there is little factory support the odds are even the best techs may never find a solution. A cheaper starting point is to replace the cam sensor and failing that swap the coil packs yourself and see if the misfire code changes from one cylinder to another. This requires no special tools and is a quick way to find a bad coil pack but ive yet to find a bad coil pack. Seems no one seems to know what causes this but it is a REAL concern when you have your kids in the car. It should be a safety recall but within corporate automotive politics, Chrysler, Daimler and Fiat will never soak up the bill, admit blame or provide a proven technical answer. They have enough recalls already so dont expect any support from them on these 12-17 year old cars.
* Computer Software Updates
Like most modern cars and home computers there is a strong probability your Jeep's computer software needs to be updated and only the dealership can do this. Its best to call them and ask firstly if there are any open recalls on your Jeep (you will need to supply them the VIN #). If you are having a problem it might be a good idea to have them upload the latest software first as there are dozens of TSBs and recalls for the Grands pertaining to software. If you're not having an issue then its best to just let sleeping dogs lay so dont mess with something that isnt broke.
* Rear Wishbone Suspension Balljoint
This is the balljoint centered over the rear axle. It connects the axle to the upper control arms. Its a common wear problem and is worse on lifted WJs without a spacer. Its a long term routine maintenance item that can cause an out of control car if the bolt snaps. The common complaint is clunking in the rear. Inspect it with a prybar for play - you shouldnt see any play. Like tie rods and control arms, if there is any slight movement then you need to replace it. Its not a fun job and you need a big socket and spanner to replace it.
My two cents. Please tell us yours
Common WJ Issues
Baby Vader
Grand Wookie Jedi
(that was the head that had dropped a seat).
. Mine's good though and well abused. lol!
