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mcware 02-08-2011 10:58 AM

2002 jeep wrangler engine failure
I own a 2002 jeep wrangler that had an engine failure. it has 67000 mile on it. at the last oil change, i switched to castrol synthetic oil. after about 1000 mile the engine failed. the oil turned to a gum like substance. i have owned the jeep since new, always serviced it faithfully and it has never been in the mud. it is a 4.0 litre. any suggestion. :confused:

InfernoGirl 02-08-2011 12:08 PM

Pretty sure switching to synthetic is a bad idea on an older vehicle. I think it loosens all the build up and probably is what created the crud. I'm sure others with more knowledge than I will chime in soon. Sorry about your bad luck. :(

KCrisp 02-08-2011 06:43 PM

I've switched to synthetic in many older engines and never had a problem. If you have been using modern oil and changing it as recommended you just don't have a big build up of gunk to become loosened/dissolved. What "failed" in the engine, exactly? No cracks in block or head or leaky head gasket contaminating the oil with coolant?

JDsDream 02-08-2011 07:24 PM

My first thought was the head gasket. Is there oil in the coolant or vice-versa? Did it overheat before it failed? Were there no signs that it was about to go?

ratuna 02-08-2011 07:36 PM

Who has been doing your oil changes? You or a Goofy Lube type place?

jefferyfghezzi 02-08-2011 08:26 PM


mcware 02-09-2011 10:57 AM

I wasn't driving, so i will tell you what my wife told me. Driving down the interstate, engine light came on, and then a loud band. No sign of overheating before the failure. Started pulling parts off yesterday, and found a hole in the side of the block. Haven't removed the pan yet, but sounds like a rod came loose. No oil in the radiator or coolant. I changed my oil myself using 10w30 pennsoil, before switching to synthetic.

jefferyfghezzi 02-09-2011 03:31 PM

Sounds like you spun a rod bearing and broke the rod. With only 67,000 miles on the JEEP I would probably look for remanufactured short block. Your crankshaft more than likely is scored. A salvage yard engine is good too,but I wouldn't want more than about 70,000 miles or so on it. Not knowing how it has been maintained I would be tempted to rebuild it just for the peace of mind. If you opt for remanufactured I wouldn"t want 10 or 20 under on the main or rod journals. I have gone 30 over and had no problems on the mains ,but I did have problms on the rod jounals.Thats just me.

PTaylor 02-09-2011 03:34 PM

you can get another engine pretty cheap, just the basic engine, and transfer everything from it to the new engine.

or sell it to me as is....

Tomb Raider 02-09-2011 03:39 PM

67k blows! Sorry for the loss! Never had issues with changing to synthetic in all my vehicles, old and older. Having worked in a race engine shop...sometimes things just happen, and specific causes go un found!

buckstom 02-09-2011 05:46 PM

Even used engines aren't cheap
There are so many engine failures that even a used engine will cost $1200 to $1600. I looked everywhere and Advance Auto had the best price. They give a year unlimited mileage warranty on the engine itself. The labor is on you.

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