11th Oct 2016, 15:15
My 2000 Jeep overheated. Got someone to look at it. I needed to replace the radiator cap and went ahead and changed the thermostat, and it was still overheating, so the next thing I replaced was the radiator fan relay switch and that fixed the problem... But now 2 months later I hear a tapping/knocking sound under the hood. What can it be? I do need a oil change. I'm close to 400 miles over the service date and the knocking sound didn't come till after the mileage I needed changing.
11th Oct 2016, 18:50
Maybe the oil level is low. You also ran the car hot; not sure how long. A trick I have done on old cars is to run the heater when in traffic to cool it down. My newer cars with 2 electric fans I run the air. Kicks on fan 2. It's smart to flush coolant ahead of schedule, especially ones with Dexcool.
3rd Oct 2017, 03:42
2000 Jeep Grand Cherokee Laredo 4.0L.
Here in the rust belt, I noticed good and bad under the chassis. The good is the floor boards are not rusted through, but the gas tank skid plate looks like rust hell. A huge chunk is missing in action. The gas tank scares me as it hangs down in the rear like a sack advertising someone to smash into it and kill us both. I ordered a Walmart class 3 hitch that will wrap the back with 1/4 steel tube that may save my life, or at least give me a running start before the Jeep explodes in flames ala the A-Team. For $1000 everything works, new battery and starter, extra chip key and a programmed remote to stop the friggen alarm system from blaring, the tires need to be changed, front rotors and pads done, the rears look OK.
There is a drip leak from the transmission, I think it is an o-ring on the fill tube. I was going to change the trans filter, but added some Lucas conditioner instead. Oil filter looks new, oil is full, oil change oil is not too dark.
I sprayed all the electric connectors with WD-40 and greased all the joints. No squeaks from the drive train, but the 4WD is tweaky, feels like u-joints.
Bad rust on both front fenders, but not the rest of the body.
I think the people that owned it had 800 children, but I scrubbed the fabric and carpets with foaming magic spray and wiped away many boogers, then a good spray down with foo foo made the interior tolerable. I have some leftover wheel paint and clear coat from another jalopy, so the wheels are getting a fresh coat with the old tires still on. Who cares! Out with the old! I have a set of timberline tires on watch, they are made by Omni for the shoe brand as a recycling thing. I think the tires will be OK, cheap as chips!
For all this trouble, the engine and trans work good, 4x4 works, engine is quiet with 175,000; I can tell this has had oil changes. Replaced filters air, fuel, and blasted my neighbors with white Seafoam smoke to clean out the carbon. Oil pressure is nearly 60 PSI, OUTSTANDING! Everything seems to work good, but I haven't taken a long trip yet until I get good tires and the title transferred.
If you have read this far, you have no life, and love old Jeeps :)
23rd Oct 2017, 10:37
Cracked cylinder head from bad batch of heads made from 99-01. Needs to be a class action lawsuit.
4th Apr 2018, 18:25
We should push for a recall. I just bought a 2000 4.0, 146 thousand, a nice car. It started making a funny noise and just quit. It cracked a head, which then lead into a piston blowing. This should be a recall for this; had I known I needed to change the bad 0331 head, I would have done so. Now I'm trying to find a reasonable engine for this.
28th Dec 2018, 03:16
I acquired a 1999 Jeep Grand Cherokee Laredo with 4.0 straight 6 cylinder engine.
Symptoms: Losing radiator fluid but no visible leads?
Came to find out some of these models through this period had the cylinder heads cast in Brazil I think it was. Anyway, they have a thin casting between cylinders 3 and 4. Very common for these to develop a crack.
Solution: Replace the head, rocker arms, push rods - top of engine. About 4 hundred if you can do it yourself.
31st Dec 2021, 01:50
Could be your thermostat is stuck partway open. Just happened to my brother's 2000 Cherokee 4.0L. Coolant backflows and overflows due to the thermostat won't open fully as residual engine heat transfers to coolant. Since the engine is off, the system relies on natural circulation to allow hot coolant to flow to radiator. Coolant volume expands as it heats up. If it heats up faster than the now static radiator can remove heat, the reservoir will fill and overflow. The level then shrinks as the engine cools down and you end up with a lower coolant level in it.
27th Apr 2023, 23:46
The radiators in the Jeeps are too small.
I had a Laredo with a 4.0 liter. I bought it from a friend. He told me it keeps overheating.
One day going through a canyon in California, going up it over heated and red lined. Blew the head gasket. My friend had changed the fan clutch, water pump, thermostat, hoses, fan blades-fan. Still was overheating.
He was off road one day and hit a jack rabbit. Took it to the dealer to fix it. They put a new radiator in it, the same type he had in it. But kept getting hot. When I was driving it thru the canyon and it red-lined and blew the head gasket, at least I was able to coast home.
6th Jun 2015, 20:32
Bought a 2000 JGC from a dealer in 2003 and it's been a great vehicle, never had any major problems and most of the minor problems are easy fixes; figured I'd pass along what I've learned to help anyone who comes across it. I'm not a professional mechanic; these are fixes I've found researching online and via other Jeep owners.
Tail lights: could be several things. Inside the light assembly where the sockets screw in, there are tabs that sometimes don't connect with their corresponding tab on the bulb mount. Using a small screwdriver, pry them up very gently until they are above the plastic housing so that they make good contact with the bulb mount. Also be aware that tightening the bulb mount all the way may misalign the tabs. I used a marker to mark where the tabs were and lined up the marks: no problems with the lights since. I've also heard that shorts can occur with the ground, which is behind the front passenger headlamp (this is via my brother-in-law who is another avid Jeeper).
Slipping transmission: Low fluid. Jeeps need to be at operating temperature on level ground with the engine running to accurately check the fluid (which a lot of mechanics/oil change specialists aren't aware of). I put a little over a quart in mine and it works fine. Where the fluid goes is another matter; my leak is a bad seal/washer at the front of the transmission, but it's so slow I'm not too concerned.
Engine turns off when hot: Mine was the transmission position sensor (replaced twice). The part itself isn't that expensive (less than $100 online last time I looked), but unless you have the right equipment it's almost impossible to install yourself. The two times I've had mine fixed labor was about $200 if I remember correctly. Not ideal, but when your motor runs reliably it's worth it.
I am very happy with my Jeep and will likely buy another one when this one finally bites the dust. Good luck to everyone!