common wj jeep problems

[Chad]

Most common problems with 4.0L and 4.7L jeeps. From my experience owning two WJ jeeps.

1. Oil leaks from rear main seals, valve covers and oil pan. High mileage oil seems to help. Rebuild with new gaskets

2. Burns oil at higher mileage. High mileage oil and or thicker viscosity oil seems to help. Rebuild engine.

3. 45rfe transmission problem : Solenoid makes noises when shifting gears or coming to a stop in neutral.

4. Transfer cases tend to leaks. Rebuild, replace or keep filling up with fluid.

5. Power steering pumps leak like a siv from the hoses and leak onto sensors creating other problems. New redesigned pump and hoses fixes the problem.

6. Carbon buildup in throttle body- a design flaw – periodically clean the throttle body with throttle body or carb cleaner, use chevron techron additive once a year.

7. Throttle position and idle air control sensors fail. New sensors installed as needed.

8. Bad sludge in the oil fill cap and valve cover- Design flaw with the pcv system. Updated pcv valve and synthetic oil changed every 5000 miles remedies the problem.

9. Lifter/ lash adjuster tick on cold startup- 5w30 motor oil and replace lifters/lash adjusters.

10. solenoid clicking- EVAP solenoid makes annoying noise when car is running. People on google says its normal and dont worry.

Topic

[EricTheCarGuy]

Thank you for actually reading the description of the thread and posting useful information here. It is appreciated. 😉

[WILLIAM MOORE]

Thank you for the info, I own a 2000 wj 4.7 and it is pushing 145,000 miles and I have a few of those issues, leaking valve cover gaskets, sludge on oil cap, burning oil at times putting blue smoke out the exhaust, but not often. power steering line leaking. now in January I switched over to High Mileage Oil and noticed a big difference in oil consumption. before i was adding 3-4 quarts between changes. I changed over on 1/2/16 and only had to ad half a quart so far. I am a bit nervous with going with thicker oil in this motor with that many miles so I have been sticking with 5w30. It runs like a dream and my only issue with it is I have a slight miss that I only feel at idle and seems to go away when I use fuel injector cleaner or a fuel system cleaner but when I fill the tank back up it comes back like clock work, with no C.E.L. And a leaking real axle seal on the passenger side. Another common issue with the WJ is the blend doors breaking and the power window motors going bad. Other then that I love my WJ.

[Chad]

Hey thanks for your comment. Appreciate your input. My advice to you is to keep up on all the schedule maintenance. Thats the most important thing to keep your car lasting. Change out your every 50,000. Transfer case fluid every 30,000. Do a tune up: new 02 sensors, Replace your air filter, new pcv valve, all 8 spark plugs and a new fuel filter will make it run like a top again. I just did that to mine and boy it runs so much better now dude. Also good choice with the synthetic 5w30 thats perfect! Stick with the high mileage oil and a good filter is a great plan too. Change every 4-5k miles. You can bump up to 10w30 in the summer but dont go any higher than that the engine was designed with closer tolerances for 5w30 or 10w30 viscosity.These jeeps are pretty good cars mine has been a pleasure to go on vacations with. Good luck and keep me posted on if you have any questions! 🙂

[Chad]

and if you have any questions or want to chat im an ase certified mechanic and am more than happy to have a chat with you (949) 842-0678 is my number! 🙂

[wafrederick]

The 4.7 also has problems with the valve seats dropping,installed loose from the factory.If you find one that the valve seat come loose and break into pieces,throw the intake manifold away and buy a new one.The little pieces get into the intake and the intake manifold can’t be taken apart to clean it out.Timing chain problems too and is expensive to replace timing chains in it.The 4.0,1999 to 2004,piston problems and the head was casted wrong.

[Author]

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