Fun with a Pentastar 3.6L

Discussion in 'Off Topic' started by ltd02, Aug 18, 2019.

  1. ltd02

    ltd02 Comfortably numb KJ Supporting Member

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    Figured this was off topic but might be interesting to those with a Pentastar 3.6L or maybe the 3.2L that shares many of the same crappy Chrysler parts.

    So I have an Avenger of the 2011 vintage. Only about 115k on it and my daughter drives it around the Albany New York area. We've had it since 2012 and it's been a good ride until the past few weeks. I was fretting about getting the oil changed since I was pushing 8k but only use high end synths and Wix filters (cartridge). She pulls in to our halfway point in the Poconos and its tapping like a SOB... She informs me it started 4 days earlier. I of course thought the worse but it didn't sound like a rod knock. I changed the oil and found some metal in the filter but didn't look like aluminum or copper. Didn't think to check it with a magnet. Only taps when warm.

    Now we knew for a few years (maybe since 2014) about the select few Left heads from 2011 to early 2013 that were not cleaned properly post casting and very bad things happened when the casting sand circulated. Also many have had issues with valve seats in the Left head as well.

    Well this is a tale of rocker arms... Apparently the rocker arms in these things are basically crap. The needle bearings in the roller wear as does the center pin. I spent several hours this weekend tearing into the Avenger and found one of the cylinder number 5 intake rockers completely frozen and depressed enough that it was starting to groove the outer edges of the cam lobe. Now we probably drove this thing about 700 miles since the tapping began and I guess were very lucky. I swapped a Melling in and lucked out since it was far from the chains and I just loosened the caps for a bit of clearance. I checked the rest but they seemed very good and figure WHEN it does this again I'll just change all the rockers and lash adjusters at once. I don't have the cam locks to do all 24 valves as the cams would have to come off.

    My research shows this to be a very common issue with all Chrysler variants with the Pentastar. I also found that the replacement rockers fit the 3.2 liter we see in the KLs. I've seen examples of this issue all the way up to 2017 so far. So just a heads up in case you hear a troubling tapping coming from your 3.6 or 3.2 L engine someday.

    The bad rocker was on the right side buried close to the cowl so here's a pic of the left side showing how nice and clean the internals are with 115k mostly highway miles and oil changes on a 7.5-8.5k interval:

    IMAG0865.jpg

    Anyway just a heads up. I was looking seriously at a 2018 KL but now I probably won't be investing in another Chrysler product when the KJ and Avenger leave the fleet.
     

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  2. LibertyTC

    LibertyTC Well-Known Member Staff Member Moderator

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    Sure makes you wonder about quality control, and no re-calls.
    Do you think it would be best advised to change the oil at 3k miles for the sand casting issue alone?
     
  3. ltd02

    ltd02 Comfortably numb KJ Supporting Member

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    Well I must say that Chrysler extended the warranty to 10 years and 150k for tapping/knocking/cracking issues with the LEFT head. It seems most problems arose early and were more cooling system related. You know how these things like an overheat. I guess the "stuff" would cause cooling circulation issues and often resulted in valve seat issues or heads cracking. This warranty probably would apply if the bad rocker was in the left head if you fussed enough but really the rocker issue is a different problem and one they don't seem to cover except under the original vehicle warranty. I doubt frequent oil changes would do much for sand in the oil passages. I would think that once the stuff started circulating it would be filtered out quickly and not continue to circulate, BUT the damage would already be done to bearing surfaces and cam lobes and crank journals. Of course frequent oil changes wouldn't hurt...
     
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