2002 4.7 Grand Cherokee. Opinions?

[saybye]

Whats yall experience with the 4.7? I see a lot on craigslist that are blown up and have talked to a few people that have had them go out on them. Im asking because there a descent deal Ive found on a wrecked, roll over 2002 model. Brand new 31's and black D windows on it. Has never been wheeled. Interior is in awesome shape and its got 130k on it. Air bags didn't deploy, the a pillar and roof on the driver side is mashed in. It would make a great candidate for a chop and beat the holy piss outta it type build.

 

[Lowrange2]

I've never had one but I do know that the engines are pricey.

If you want the parts off of it I'd buy it cheap, part it out and put that money into another vehicle.

 

[PacificEd]

We had a 4.7 in a 2002 Dodge Dakota crew cab. Great engine for the time we had it. It did develop a leaking down injector problem that caused it to be rich upon start up.

When reading up on this engine, one thing is very evident. You must service it will regular oil changes. If they are neglected, deposits build inside and can clog the small oil passages.

 

[saybye]

I hope to go look at it tomorrow afternoon! Looks like a good candidate for a beat to hell n back wheeler. Possible part out isn't a bad idea either...

 

[highspeed]

I know the engines are hard as hell to work on and expensive to replace........or at least they use to be. Should be easy to find parts for them now though.

 

[shelbyluvv]

I had a 2004 WJ that I gave to my son. See my avatar pic. The Jeep has been wheeled all over the east and west coasts. It never missed a beat. The only issue it ever had was the TRS went bad in the transmission.

A bit of a warning though. WJs do not like to be lifted. They will develop DW very easily and it is hell to get rid of.

 

[highspeed]

I had a 2004 WJ that I gave to my son. See my avatar pic. The Jeep has been wheeled all over the east and west coasts. It never missed a beat. The only issue it ever had was the TRS went bad in the transmission.

A bit of a warning though. WJs do not like to be lifted. They will develop DW very easily and it is hell to get rid of.

Adjustable track bars front and rear should do the trick.

 

[shelbyluvv]

You don't know what you're talking about.

1st, The WJ does not use a rear track bar.

2nd, The front end was redesigned by ChryCo to provide a smoother ride. They accomplished this by moving the CA mounts closer inboard. This in turn can and will set off DW very easily. If you don't have everything spot on in the front of a WJ you WILL get DW. It happens to stockers just a easy as a lifted rig.

 

[Georgia Mike]

My dad had one. Make sure you keep up on the maintenance. He got a bit lax in that department, didn't change the oil regularly and it spun a rod bearing. The oil passages on those engines are tiny and it doesn't take much to clog one. That's our first hand experience. As far as working on it was concerned, I found it rather easy to work on. Everything fit together very nicely on the engine, although the engine compartment could get a bit cramped with that wide mill in there lol. I *think* Mercedes designed that engine? Who knows. I think someone told me that once but I never investigated its history.

The bad part about it is that the noise sounded like a lifter ticking. I'd have bet my paycheck that it was in the valve train. My dad didn't want to fool with it any more so we sold it. The new owner informed me of the rod bearing being spun.

 

[saybye]

well I went and looked at it and it wasn't what I thought it was going to be. either way great feedback, makes me a little more confident in buying one with a 4.7 now!

 

[highspeed]

You don't know what you're talking about.

1st, The WJ does not use a rear track bar.

2nd, The front end was redesigned by ChryCo to provide a smoother ride. They accomplished this by moving the CA mounts closer inboard. This in turn can and will set off DW very easily. If you don't have everything spot on in the front of a WJ you WILL get DW. It happens to stockers just a easy as a lifted rig.

Damn bro, chill. I thought I remember them having similar setups to a ZJ, which do have rear track bars. Sorry if I got your panties wadded up.

 

[thechief86]

My buddy has one, and at 120k all of his computers that run the fuel injection and transmission have crapped out, or so the dealer says, wants $2500 to replace them. I replaced the solenoid pack and valve body in the trans, and it still won't shift. Takes off in 3rd and stays there.
We have replaced the ecm with 4 junkyard units, and decided that they must have been there because of bad ecm's. So he took it to the dealer to have one put in, and the charged him $1000 or so for it, and the jeep ran fine for a month, around 600 miles or so, then started the same crap. So back to the dealer, and they say that now it's a different computer, and they won't promise that will fix it unless he pays to replace the ecm again, as well as some other module, so back to the $2500 mark. The jeep is now sitting at his house and he is DD'ING the 93 xj he has with over 200k on the dash.
I believe I'd pass on the wj....
That said, his looks great with custom bumpers and lift, and did well offroad with lockers and 33's, and is very comfy and sounds awesome with the full MagnaFlow exhaust, lol. He's got too much money in it to scrap it, so we're trying to figure out if we can make a chevy or toyota drivetrain work in it...

 

[shelbyluvv]

I'm totally "chill" bro. I don't like seeing bad information passed around on forums though. The WJ is a totally different beast than a X/M/Z/TJ when it comes to suspension and steering. While the front ends may look similar they are very different and less tolerant of things not being exactly correct.

Here are a few things that have set off DW on my WJ.

brand new track bar with to soft of bushing material,
a slightly warped rotor,
.25* to little caster,
1/16" to little toe,
one tire missing 1/8 of weight,

these were all diagnosed at different times after the Jeep devolved DW. As you can see the WJ can be a finicky little shit when it comes to the front end. The rear three link can be another PIA and cause drivability issues.

 

[shelbyluvv]

My buddy has one, and at 120k all of his computers that run the fuel injection and transmission have crapped out, or so the dealer says, wants $2500 to replace them. I replaced the solenoid pack and valve body in the trans, and it still won't shift. Takes off in 3rd and stays there.
We have replaced the ecm with 4 junkyard units, and decided that they must have been there because of bad ecm's. So he took it to the dealer to have one put in, and the charged him $1000 or so for it, and the jeep ran fine for a month, around 600 miles or so, then started the same crap. So back to the dealer, and they say that now it's a different computer, and they won't promise that will fix it unless he pays to replace the ecm again, as well as some other module, so back to the $2500 mark. The jeep is now sitting at his house and he is DD'ING the 93 xj he has with over 200k on the dash.
...

Check the wiring going into the doors from the body wiring harness. Look for broken and cracked wires. Mine did the same thing. Lost all power to the OHC, no heater, radio, dome lights staying on or not working at all, relays randomly clicking behind the dash, not starting, not shifting and a bunch of other weird little issues.

Mine had broken wires in all 4 door harnesses. This was causing wires to ground out on the body and was freaking the BCM out. I repaired all the wires, disconnected the battery and touched the terminals together for 30 seconds, then fired it up. all the problems went away.

 

[thechief86]

Thanks! I'll let him know, he really loves his wj but has thought of getting rid of it for less than a grand just because he couldn't figure out what's wrong with it.
Never would even think that the transmission problems could start at the door jams, lol.