Chad R Posted June 9, 2023 Share Posted June 9, 2023 I just broke a piston in my 2001 Jeep TJ 4.0L. How common is it and has anyone else have this problem. My TJ had 93k on it and very well maintained. Link to comment Share on other sites More sharing options...
FrankTheDog Posted June 9, 2023 Share Posted June 9, 2023 It was a problem with some 96-97’s. They would develop wear around the wrist pin and eventually blow if you didn’t take care of it. Quite possibly that’s what happened to yours. Although the 96 I had was really noisy before it let loose at 82k. Link to comment Share on other sites More sharing options...
FrankTheDog Posted June 9, 2023 Share Posted June 9, 2023 It was a mint 96XJ and l bought it at a junk yard with the piston noise. It was really bad. I drove it home but it let loose before l got there. I had a wrecked 96 with identical mileage and swapped out the engine and transmission and drove it to 355k with no further internal engine problems. Link to comment Share on other sites More sharing options...
Chad R Posted June 9, 2023 Author Share Posted June 9, 2023 It had a little more than the normal 4.0 tick. I thought it was a lifter starting to go bad then all of a sudden it got loud so I thought I lost a lifter. Tore it down no play in valve train. Pulled head to check lifters. A mechanic friend that does engines told me to pull pan just to check and found piston chunks from #5 Link to comment Share on other sites More sharing options...
FrankTheDog Posted June 9, 2023 Share Posted June 9, 2023 Lifters tick. Pistons clack. Hit some of your piston pieces together. You’ll probably recognize the sound. They go bad around the wrist pin. Maybe to much clearance when it was assembled. Or faulty piston castings. Link to comment Share on other sites More sharing options...
FrankTheDog Posted June 9, 2023 Share Posted June 9, 2023 Was this in the Wrangler you just bought? Link to comment Share on other sites More sharing options...
Chad R Posted June 10, 2023 Author Share Posted June 10, 2023 No, my 2001 that I bought brand new. I had to buy that black 01 because I’m a trail guide for the Drummond island Jeep jamboree and I have to be there. We were going to buy the black Jeep anyway but it wasn’t going to until we got back from Drummond. So Wednesday when it was determined that my original 01 was not able to be fixed in time we bought that Jeep because I have to be on Drummond on Monday morning for pre running. Link to comment Share on other sites More sharing options...
FrankTheDog Posted June 11, 2023 Share Posted June 11, 2023 I’m guessing it is a manufacturing defect. I replaced mine with a similar build date and mileage 4.0 that never let loose even after being hydro locked. It wasn’t on the road much longer after that but that was because the body was becoming much to porous. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now