ORVBulletHoles

Hi there, newb here.

So far I have done my reading and I can come up with the following:

- When was transfer case fluid done?
- When were timing chains done?

From my other cars I'm guessing chains every 80 - 100k kilometers (sorry not sure about miles I am Canadian) and maybe the same for transfer case fluid.

I understand these are the major service areas..any other vital areas to check for these vehicles?

Looking to get into the V8 but I hear it's not the greatest V8 and the V6 is just as good, any truth to this? I want to put a nice exhaust on it I hear a lot of nice setups on YouTube.

Also I am willing to pay a little more and get into an '06 or '07 but I wonder if these are as good? I hear people say the previous generation is better.
Basically these two generations are in my price range ($3000 - $10,000). Another reason I'd rather go a generation down is to have more $$$ leftover for upgrades.

If I do pull the trigger on one of these I probably won't lift it but just put slightly bigger tires on it, exhaust, cold air intake, etc., and focus on stuff like dash cam and navi because I plan to do a few drives down to the states so it has to run smooth on highways and be functional, not looking to off-road. That being said, any must-have upgrades you guys recommend? i.e. Popular aftermarket billet parts for engine components that fail often etc. or chips?


Thanks a lot for any help!

Bustedback

2004 was the last year for the solid front axle. IFS can be expensive and tricky to lift for larger tires. The 4.0 I6 is as bullet proof as they come. Kinda down on power, but last forever. The 4.7 V8 has power, but does not handle abuse well at all. Run it low on oil or overheating it once is all it takes to turn into a boat anchor.

dave1123

I've no direct experience with the 4.7 or the 3.7, but it has come down thru my grapevine that the timing chain guides are plastic and if they break from a worn chain, can let the chains jump timing and break thing like valves and pistons.

ORVBulletHoles

Thanks for the info guys
So I think I like the sound of the inline 4.0L Inline 6 motor.
Bulletproof is always good in my books and come to think of it, it'd be better for gas mileage. If the V8 is that fragile I'd rather not bother because most of these are over 200,000k kilometers.

Noted about the timing chain guides. I think these usually get changed out with the chains service? Any ideas on how long they last? Again, I'm guessing every 80 - 100k kilometers based on the V6 Volkswagen I used to own.

Any other things to look out for with these 02 - 04 Grand Cherokees?

Thanks a lot!

Bustedback

Don't expect great, or even good gas mileage out of the 4.0, it's probably only a mile or two per gallon better than the V8. The best I have ever got in my ZJ was 22mpg on the freeway at stock height and tires. Once I lifted it and put 32's on it I'm lucky to get 15mpg. You don't buy a Jeep for gas mileage.

ORVBulletHoles

That's a shame but o well I guess you don't buy these things for the gas mileage heh.

ORVBulletHoles

Just found this gem, answered my own question.
Transfer case fluid for Quadra-Trac II and Quadra-Drive transfer cases is every 24mos.
http://www.wjjeeps.com/service/maintenance_wj.htm

Incidentally no replacement of timing chains is recommended until it's way over 150k more like 200k miles, during major overhaul. Also, 4.0 i6 is not an interference engine so even at worst case scenario and the timing chain slips a tooth somehow or breaks my understanding is there should be no slapping of pistons and valves (I guess that's why they say 4.0 i6 is bulletproof).

i remember I used to have a VR6 Golf and the VR's had timing chains and you'd hear them long before it was really time to have to change them so, I think unless we are talking super-high mileage motors that have been beaten hard I should be okay.

Fred/N0AZZ

I have an 04 WJ with the 4.7HO V-8 engine has 229,000 mi and running very strong had over 200,000 on it when I bought it but it looked and drove like new.


The 04 is the newest Grand I personally would own for reasons listed above. Avoid the 99-02 4.7 engines as they were prone to more problems, changes were made in 03 for the better in them.


Mine does use a drop of oil when I change it every 6 mo. or 6.000 mi. I have owned it now for over 6 yrs. only issue was recently was a TPS had to be replaced.

ORVBulletHoles

Thanks for your input.
What changes occurred with the '04 that makes it less issue-prone than the first few years? Also what's TPS?

So yours burns a bit of oil? Ever had it pressure tested? Or do they all burn a bit of oil?

Bustedback

Every engine uses some oil, it just happens. A quart in 3000 miles is considered normal.

dave1123

TPS= throttle position sensor.

I'd be concerned if my engine didn't use any oil. A quart between oil changes is normal.

rzldzl

4.0 is a better motor, yeah...but the trans behind it is hot garbage

also check the blend door

ORVBulletHoles

Understood about the oil.
TPS - throttle position sensor, got it.

Regarding the 4.0 tranny - can you elaborate more on why it's no good?
Is the tranny with the V8's better?

Having a weak tranny is something I'm def. not interested in.

I liked that the i6 was bulletproof - is there any year where the motor and the tranny are equally sturdy?
Blend door - what's that?

rzldzl

google 42re trans in the 4.0 wj

google 545re trans in the 4.7 wj

choose your gamble....i want a 04 overland red (4.7)

blend door...in the dash, door operates the hot/cold for your hvac....$1500 to take the dash apart to fix it, or diy it for ~$50

the blend door broken is very common, surprised you havent 'read' aboot it yet

ORVBulletHoles

Do you mean 545rfe? Most of the information I found is about 545rfe not 545re. Looks like people's experiences are varied and it comes down to maintenance, although the 545rfe is supposedly stronger b/c it has 3 instead of 2 sets of planetary gears. (If properly maintained). A deeper aluminum pan and transmission cooler upgrade are recommended for it.

The 42re has the lowest torque rating at 2 so I guess that's why it's weak. But again people's experiences are varied. They say you can rebuild it with 44re internals but the 44re won't bolt directly on. That sounds like a PITA.

I guess the bottom line is find a vehicle with service records that has been maintained. That being said, the V8 mated to the 545rfe sounds like a better choice provided the motor has been maintained and not turned into a boat anchor as mentioned above.

I've been mostly reading about motor maintenance so the blend door didn't come up. I have read 'aboot' it though!
http://www.jgcparts.com/JeepHeater.html

So if she only blows cold now I have my solution, thanks for the info!