Replacing lifter adjusters and lower bearings...after only 37K miles!

History:
A couple of weeks ago my son mentioned that he heard anoisecoming from theengine. After a week of investigation, Idiscoveredthat my3.7L has a cold-start knockwhichseemed to disappear after a 3-4 min warm up.Warm startthe engine(within 1-2 hrs after being warmed up), and the knock isnot there. This is obviously similar to othercomments Ive read hereon DF, even though the most common complaints were those with 4.7L.Perhaps the bestway to describe thesound is to say its like having adiesel when idling cold.A slight increase in RMPmakes the knockdisappear. None of the following had any affect – changed oil, filter, plugs and a fresh tank of gas.

Idropped it off at the dealer last week to let them see what they could find.At first, I thought it might be a simple knock sensor, but after reading the Service Manual it was clear that the knock sensors are only used during acceleration. Service initially indicated theycould not hear the knock, but after keeping the car for another day,theyconfirmed the sound, dropped the oil pan andcheckedbearings. Theyinformed me that parts are on the way and that theyintend toreplacerod bearings & lifters (lifter adjusters).

Shortly before the factory3/36ran out (~2 weeks ago), Ithankfullydecided tobuy the7yr, 100k extended service contractfrom Chrysler.... Although the contract pricewas outrageous ($2k), apparently it will be worth every penny!

After drivingmy backuptank (88 K5 Blazer),I suremissmy Dakota.

hlp

 

That Sucks 37K??????

 

What they are doing will not solve the Diesel sound you hear. Its been tried and does not seem to work. I have the same problem, but with my 4.7. I do pray that it does work for you though!

 

It sounds like your dealer is doing this as a precautionary method. Did they actually state what was causing the noise? Is there some sort of wear present?

I have the exact same noise during startup. Most of us have some form of it. It seems to be more pronounced during the summer for me, but I have my windows down then lol.

I consider it normal.

 

MonkeyWrench4000 is right. I have it too, and it comes and goes. Sometimes weeks between issues. Now that I park indoors, when it occurs, I really hear it. The guy beside me has a cummins diesel, and he actually thinks mine was a diesel at first!!!

 

Dealer indicates that there wasmore than acceptablerod bearing clearance which they stated was verified viaplasti-gauge (sp?). I believe that the lifter adjusters are being replaced asa precautionary method as you stated... but thatsjust my opinion at this point. I'll know more afterthe repairs are complete and I have a chance to talk to the tech & service advisor in more detail (later this week).

Over the past week or so I've read all thepost on DF about thisissue.I also have my doubts aboutthis repairresolving the knock. If somehow I end up in the minorityand thisactually fixes the knock issue,whoknows ifit will reappear and when? If the knockcan not be resolved orif it returns,thenI willprobablytrade herin at years end becauseIMHOa2.5 yr oldvehicleshould not sound like our 16 yr oldCaravan.

Viper, you stated that the sound comes and goes... but mine is (hopefully was) very consistent. Every time I start the motor when cold (with 70-95 deg ambient).

Thanksfor thatprayer, hopefully it will work!

hlp

 

Good NewsUpdate:

Picked up the 06 Dakota today… after they replaced all six rod bearings and all12 lifters/adjusters.Service advisor andTech both indicated the cold-engine knock was definitely gone(verified by different 3 cold starts on two different days).Since the knock was consistent, it shouldbe easy to verify tomorrow morning.

Details: The service Tech indicated that two of therod bearings (cylinder 5, 6) had too much clearance but no measurement was given. As for the lifters, he indicated that two of the lifters were bad (one intake and one exhaust from two different cylinders - he didn't recall which cylinder numbers). Heindicated the service order was written up to replace all rod bearings and all liftersto ensure one of the others did not end up withsimilar problems.






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After two full days and a 1/2 dozencold starts, my 3.7L cold-engine knock/Diesel while idling is definitelygone! Now all I hear is the typical Fuel Injector ticks

If anyone else is experiencing this problem andis still underwarranty orservice contract, you can have you service departmentcontact Bob Mayberry Chrysler Plymouth Jeep in Monroe, NC aboutmy service invoice 194372 (see abovepost with invoice JPG). When I called today to thank the service manager(Danny), I askhim for the total cost for this repair. Thetotal ended up being~$1200. Damn glad I decided to buy Chryslers Service Contract.

hlpruner

 

I have the same thing going on. Just noticed rod knock at idle, yesterday afternoon. I think I will take it into the dealer.

 

Damn.

I really don't want to go to the dealer again man lol.

I have been there for so many steering issues....among other things. I am getting a little tired of dedicating so much time to this pickup..