what is is with 02's and blowed up engines?

seems like it's not a matter of IF but WHEN an 02 will wad up it's lump hard. what is it about them that makes them so prone to failure, and what if anything can be done to prevent it, short of replacing the engine with something newer?

never heard of a problem

They have the same prones that the rest of the 3.7's do. With a year more run-time

I just seem to see so many passing by with comparatively low miles (< 100k) and the motors are trashed. were people doing something wrong with the maintainence/oil changes on them? and yet I don't see 03 or 04 MY's with nearly as many blown lumps. in fact I see alot of them for sale with north of 150k on the clock and still on the original engines (or at least so they're claiming.)

Lot of it has to do with maintaining the vehicle. Overhead cam V6 and V8 engines need their oil in good condition. Going too long on a given oil will lead to timing chain shoe wear, chain stretch, and bearing wear. I have witnessed it plenty of times on other engines of similar design. Overheating also plays a factor in it. The vehicles I see with the highest mileage, in general that is, 250k-400k miles, are the ones that the owners took a vested interest in taking care of them. Oil changed regularly, and maintainence done when called for, ie plugs changed, timing belt replaced, etc. Overall, they tend to have the lowest repair expenses. I think you will find that most of the engine failures you are hearing about are related to poor maintainence at some time in the vehicle's life, and could very well be before the current owner bought it.

I have seen the pics and read articles in trade magazines about the dodge hemi engines suffering catastrophic valvetrain failure with low miles, ie bent pushrods and valves, with not alot of miles. Those were tied to owners convinced 20w50 needs to be used in anything running on gas, lol. Lesson here, use common sense, ask questions when in doubt, and follow the oe schedule when all else fails at the least.

the oil return passages are too small, the valve seats / valve locks are of poor design

there are improved parts available, but as far as I know at least prior to 2006, Chrysler didn't implement them

These issues are also the same issues the I4 has and numerous other manufacturers heads.

Just remember, you never really hear about the 9x% that never have a problem, what's worth mentioning? So what you DO hear.. is the percent that have catastrophic failures etc

That's a shame! But i still do not think that you would have problems unless you do the regular maintenance such as oil change, spark plugs, timing belts, air filter and etc. Change the cheap parts so you prevent spending tons on an entire engine!!!

Well no timing belts in the 3.7 V6.

Use the correct weight oil(5w-30 for all years) and actually change it when required(3000 miles) and all the other stuff on time and the chances are the engine will last a long time.Yes you hear all the horror stories on line but that is less then 0.1% of total engine production.


Many think not being ******* the engine will make it last,not true at all.10 years and I take mine to redline at least 10 times a day.

200,000+,change oil at 3000m or less,use Fram or anyother name brand filter. Bounce it off the rev limiter regularly. Knock on wood.

Just my opinion
Anything made by man can go wrong sooner or later, so sure some may "blowup" for one reason or another same with any engine ever built. Some sooner/some later.
People will say the 6 Jeep used for years is junk yet I've ran three up over 260,000 ( one 265,000, other two over 300,000) and no problems at all, never had the valve cover off of any of them.
Maintenance is key no matter if its a lawn mower engine or a fully built/balanced/blue printed BBC.
As far as running them hard, I'm with Troy you have to "exercise " them daily.
One of the first Harleys I had back in the 1970s I rebuilt with the help of an old Harley mechanic, when I got it back together he stopped over and I said something about riding it easy for a few days. His response was "I know how you ride everyday, you've never given it any slack before, so break that :favorites68:shovel in the way you're going to ride it, if its going to come apart, it'll come apart. So break it in right!"
My 3.7 is over 162,000, 03CDKJs is at 186,000, T-Birds is I think 185,000 or so, thats just three off the top of my head with no issues.
Run em till they blow then upgrade!

my 02 2.4l is at 180k with no issues.

I'm with everyone else. Drive it like you stole it and change the oil when you're supposed to. You'll get some miles out of it.

I stopped at a used car lot to look at an 02 sport and 03 limited. The 02 had 150k and the 03 had 180k. Both seemed to run fine and were in good shape. I hope both our JK's last that long or longer. I change oil every 3000, air filter and plugs as scheduled.

Speaking as one of the people who has had engine issues (dropped valve seat), I'm quite certain that my problem was self-induced. I'd gotten into a mass amount of mud when off-roading that coated my radiator. I had overheating issues afterwards, even after cleaning it out - never redlined the temp gauge though. Found out later that I had missed a whole bunch of (now dried) mud between the radiator and ac condenser... but my KJ had been running hot for awhile at that point. I claim complete responsibility for what happened with mine. Luckily I'm very good on OCI's and other maintenance items. All it took was one error.

But also what Jarhead said as well. When researching the fix for my engine problem, we were told by a few seasoned mechanics of the engine design flaws in the 3.7's - steel vs. aluminum construction, etc.

Regardless of all the above, we spent under $300 total to repair my engine, including having the passenger side head rebuilt. It's been doing great ever since and mine will roll over 175K miles by this time next week.

My 2002 Renegade parts truck had the engine blow at 95,*** miles and the p.o said that they had no idea why it just went one day while they were driving it. When I looked in the owners manual i see that they had the dealership do all of the scheduled maintenance (including the oil changed every 3k miles right up until 2k miles before the engine blew) i have no high mileage KJs at the moment though, my 02 Sport has 80K, my 03 and 04 both have around 110K but they all run perfect and get the oil changed every 3k miles

anything can be improved upon - no such thing as perfection

romp on it till it blows, when it does, fix whatever shortfalls the penny pinchers allowed