On 9/24 I started up my Nitro in the garage and I heard a knocking noise. It didn't go away even after several minutes. I called the dealer service team and they had me bring it in right away. The knocking noise was confirmed. My mileage thus far was 9274 miles. It was the service teams first experience with any Nitro. They were honest in letting me know it may take around 2 weeks to get to the bottom of things. After tearing down the engine they had found that in cylinder 6 the rocker arms and lifter were "collapsed". I don't even know how to change a tire so I don't know what that meant. But they fixed it for me by replacing them. I picked up my Nitro on the evening of 10/4. It sounded and ran great but after a short trip later on that very same evening the noise started again when I started the nitro. The dealer couldn't get my car into the shop until after the Columbus Day weekend, and it's still there now. They had let me know that they found that the parts they replaced in the same cylinder were broken again and they found issues in another cylinder as well. I'm told they have now replaced the whole "head assembly" on both sides (whatever that means). They wish to drive the car a little more before I pick it up this time. It will have been in the shop for 2 weeks on this occasion. I have pulled out the info sheet on the lemon law though I really don't want to. I don't want another car, I just want that one fixed. Anyone out there with issues like this? I welcome your feedback.
Collapsing Lifters/Rockers
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wow sorry to hear that bro, never had an issue with mine other than the roof rack cracking and the antenna.
This is the first that I have heard about this issue.
The good news is that you are getting 2 new heads (these are the top parts of the engine that contain the valves. Cam springs etc ---- all the stuff that broke.
Your dealer is taking the best approach here. I thing you should be OK once he does this. he is giving you half of a new engine rather than tinkering with the problem--- a good move for you.
Ken
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That's great they are replacing both cylinder heads. Sounds like you've go a proactive dealer and service department willing to go the extra mile for you. Also the fact they want to keep you vehicle a couple of extra days before giving it back to you says a lot for their commitment to getting the repair correct and your satisfaction.
On the other side of the coin, I don't understand why citizens of the US pull out the lemon law card right away when they have a few little problems with their vehicles. Collapsing lifters isn't a big deal, seen it numerous times. Its possible, and only your dealer and your copy of the repair order will say, but maybe on a few of the lifters were replaced when all of them should have been. You know tolerances are followed when engine components are manufactured, but that doesn't mean they are always perfect. When you find a perfect vehicle that never breaks down call me. What am I saying, put the lemon law to rest and, give your dealer and its mechanics a chance to fix right for you.
As a professional trouble-shooter, when I see the same failure more than once it is often due to incomplete diagnosis. They found the item that failed, but not the cause for the failure. If the same hydraulic lifter/damper failed there may be an oiling problem to that area. I am not real familiar with the 3.7 long block assembly, but there needs to be the proper supply of oil for any hydraulic lifter to work. If there is a temperature related oil supply failure to that area it will be real hard to diagnose or locate. Possibly a crack in the oil passage in the head or block that allows the pressure to drop to that rocker after the engine heats up? (Real hard to find, how do you warm up and run an engine with rocker cover off, or measure the oil pressure in an area where there is no place to attach a gauge?) On the plus side - I used to be real skeptical of dealerships tearing down or replacing whole engines because the wiring and hoses in years past were so complicated and poorly documented that it was almost impossible to reassemble correctly. After doing the same on several vehicles from the late '90's and up I am finding things much less cluttered and logical than before. I agree that the dealership is working for you and I think that if you give them a chance they will come through for you.
J
J
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539 Posts
Actually OldGuy, the original poster has the 4.0L R/T engine, not the 3.7L, but the rest of your post would apply to both engines.
I hope this doesn't turn into a common problem with that engine.
I hope this doesn't turn into a common problem with that engine.
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I have a mild knock at idle too, I hope it isn't the same problem.
I've just picked up the Nitro from the shop and so far it sounds and feels great. I suppose only time will tell whether or not it isn't something devastating such as a crack in the block and so on. Sure hope this isn't a trend. I really appriciate your input and advice to me with my troubles. Thank you very much to everyone. I'll keep you posted.
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Yes please do! (no noise in mine yet)
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wow you guys are scaring me!!!
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I feel better, mine feels as strong as ever. Must be the injectors.
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4.0Liter Engine in the R/T only
Remember the original poster of this thread has the R/T with the 4.0L engine, so all of you 3.7L engine SXT and SLT Nitros relax. This problem is doubtful to effect you. The 3.7 engine has been around a lot longer than the 4.0L that is in the R/T. IIRC, the R/T engine is a new design and not the same as the 4.0L that has been in the Jeep line-up of vehicles for many years.
Remember the original poster of this thread has the R/T with the 4.0L engine, so all of you 3.7L engine SXT and SLT Nitros relax. This problem is doubtful to effect you. The 3.7 engine has been around a lot longer than the 4.0L that is in the R/T. IIRC, the R/T engine is a new design and not the same as the 4.0L that has been in the Jeep line-up of vehicles for many years.
I recall that I saw a TSB on this somewhere.
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TSB???
Really? Let us know if you find it and I will have my dealer check my R/T for any damage or potential trouble.
It was something about valve spring replacement I think, but it seems related.
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Thx for the info Bear!!
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