Misfire 3.7, 4.7 Dodge or Jeep – Falling Rocker Arm Problem

10:52 am Chry. 4.7 Problems, Consumer, Jeep
Dennis_and_Truck
Dennis Bandy and his 2007 Dodge Dakota truck
Summary: A severe misfire with a 3.7 or 4.7 Dodge or Jeep vehicle that is accompanied with an engine noise on the top end and backfiring through the intake or exhaust could have a fallen rocker arm. This is becoming a quite common and somewhat puzzling occurrence. Learn what the leading cause of this problem is and if the repair could possibly be covered by the manufacturer’s warranty. Owners of a 3.7 or 4.7, discover what steps can be taken to help prevent this problem from occurring in their vehicles.
A misfire alone doesn’t necessarily mean that a rocker arm has suddenly fell out of place. More common causes of a misfire could be a bad coil, worn plug or plugged injector. However, many 3.7 and 4.7 engines are having problems with the rocker arm falling out of place and this is very disturbing! I personally find this troubling because I own a 2007 Dodge Dakota with a 4.7 V8. When I learned of this increasingly common issue, I set out to find the cause, the fix and steps that I can take to prevent this from happening with my truck. A misfire with a “rocker arm out of place” will be a very severe and notable misfire. There will also be a popping noise that’s most likely a backfire through the intake or exhaust. The rocker arm could be laying on the top of the head – out of commission.
It’s important to know that Chrysler does offer a 7 year/70,000 mile drive-train warranty on some vehicles between 2005 and 2007. Engine or transmission problems may be covered after paying  a $100.00 deductible. Maintenance records are likely to be required because claims for failures resulting from lack of maintenance will surely be denied (i.e. sludge). It’s best to determine if there is any warranty in place prior to starting with “tear down”. Have the VIN number handy and call 800-CHRYSLER (800-247-9753) or 877-IAM-JEEP (877-426-5337). Your local car dealer’s service department will be able to check the warranty status as well.
The first step is to scan for an engine fault code. The CEL (Check Engine Light) will surely be flashing indicating a severe misfire. Flashing CEL’s also mean that if driving continues the catalytic converter can be damaged quickly since there’s so much raw fuel being burned inside it. The fault code will pinpoint the cylinder that has the problem. For example a “P0302″ means the number two cylinder has a misfire. There’s no sense in removing both valve covers because the side can be determined by checking the firing order and locating the bank which has the problem. After the valve cover is removed, inspect for sludge, a broken valve spring and quite possibly a “FALLEN ROCKER ARM”.
Dodge_3.7_Firing_Order
Dodge/Jeep 4.7 Firing Order
 

The general consensus among several master techs that I discussed this problem with is “the main cause of  a fallen rocker arm in a 3.7 or 4.7 is from excessive carbon build up.” Carbon build up on the valve stem can cause the valves to stick momentarily. If the valve sticks for a fraction of a second too long, the rocker arm can be allowed enough clearance to fall. Other causes can be faulty valve seats or worn or defective valve springs.

Preventing Rocker Arms from Falling

One indication of carbon build up is a slight tapping noise. Usually the tapping sound can be more pronounced when cold. Detergents used today in fuel may not be enough to reduce carbon build up on 3.7 and 4.7 engines. Using an additive occasionally may be beneficial as a preventative measure. If the carbon is already built up to the point that there’s tapping, running a fuel injection cleaner through the engine may be more affective. Look at the related links below for the Fuel Injection Cleaner Kit made by OTC that every 3.7 and 4.7 owner should have. One way of knowing for sure how much difference an additive makes is to check the valves through the spark plug holes with a borescope or video camera before and after running the additive or cleaner. When it comes to falling rocker arms in these engines, one thing seems to be for sure… “an ounce of prevention can be worth a pound of cure.”

 

Related Mechanics Specialty Tools

Miller Tools Rocker Arm Remover MLR 8516A

Miller Tools MLR8387 Dodge Valve Spring Compressor

OTC 6689 Chrysler / Jeep Master Cam Alignment Tool Set 

22 Responses
  1. NewTech :

    Date: May 3, 2010 @ 4:59 pm

    I found your video to be very helpful (click here to see the video). I have a 2005 ram 1500 3.7 that kicked the rocker out. On this particular instance the roller locked up on the rocker. So a new cam was also required. The engine still has a loud ticking noise in it. Is this common for these engines or is this the carbon build up you are referring too .
    Thanks in ahead for any help.

  2. dennisb - Auto Tool Sales :

    Date: May 3, 2010 @ 6:22 pm

    NewTech, Ticking can definitely be from carbon build-up, however since the roller locked up I would be concerned that there was lack of oiling on the top end at some point. If after an intake cleaner has been ran through there is still noise, there could be other damage on the top from lack of oiling.

  3. towing new york :

    Date: May 8, 2010 @ 8:06 pm

    Nice post, thank you and keep up

  4. rob :

    Date: May 9, 2010 @ 6:27 pm

    2004 dodge ram 1500 4.7 at idle sounds like a lifter tap. when i raise the rpm the noise goes away. my thought was poor oil delivery to the top of the engine. truck has 68000 on it and i am an oil change nut every 2000 to 2500 miles. also there seems to be a bearing howl from one of the components on the front of the motor everything replaced and the noise persists. maybe from the timing cover????

  5. Chuck :

    Date: May 12, 2010 @ 3:09 pm

    Having spent more time than I care to count or could ever bill for on this problem, be aware that Chrysler has a service alert (not a TSB so if you’re not a Chrysler dealer you’ll never find it) about ‘incorrect’ rocker arm stampings. Long story short, the rocker must snap in hard with the slack adjuster fully depressed. If you’re lucky enough to encounter one of these needing a new rocker stamping nothing else will suffice.

  6. Eli :

    Date: May 31, 2010 @ 9:43 am

    Hydraulic lash adjusters can sometimes wear out given you a ticking noise and mess up your rollers and cams from not having proper lift giving you carbon. There should be no lash between the roller and cam. I just had my cams reground over sized rollers added and solid lash adjusters put in. The machine shop said my lash adjusters were the problem. Also a bit of a head gasket leak from electrolysis on the 3rd cylinder.

  7. Joe :

    Date: August 3, 2010 @ 12:36 am

    I own a 2003 Dodge Ram 1500 with the 4.7. 3 months ago my truck threw 3 seperate rockers (cyl 1, 3, and #8 ) Long story short it cost me $1,200 to have the rockers put back in. Last week it did it again. The shop said it was a known defect and would not honor their guarantee. I used my Haynes manual to walk me through the process. Though it took me almost 2 days to repair both cylinder banks, I was able to do it own my own with limited experience and no special tools. Needless to say I am now saving for a Toyota……

  8. TC :

    Date: November 29, 2010 @ 9:02 pm

    Yup…first noticed hammer sound on startup…after a few runs, sounds got worse then did an oil change with some marvel mystery oil added..hammered constantly then developed misfire..pulled the plugs and found #3 plug fouled..remove valve cover and found rocker arm laying inside. Purchased the valve tool and a replacement hydraulic lash adjuster, installed both and everything works fine…no noise, no misfire, runs like new. 2002 Jeep Grand Cherokee 150K miles…perhaps I should replace the other 15 lash adjusters. Note: Removing the valve cover is the bulk of the work..installing the adjuster and rocker took only a minute. Cranked the engine in a no start condition for 30 seconds to get oil pressure and pump up the lash adjuster. I would estimate removing all rockers and installing new lash adjusters would take only about 15-30 minutes per side once valve cover is removed. Easy fix in this case …

  9. TC :

    Date: November 29, 2010 @ 9:10 pm

    Total cost of repair .. $16.00 for valve cover gasket, $8.99 for lash adjuster. $25.00 dollars and 1 man hour..not bad :-)

  10. TC :

    Date: November 29, 2010 @ 9:17 pm

    of course, if you do all of them, the price increases..tool, adjusters, and gaskets all in all about $250.00 plus 3 man hours..in a shop they’ll charge you 1200.00

  11. Dave :

    Date: December 3, 2010 @ 11:32 am

    I have had the 4.7 rebuilt for my 03 Ram 1500. I have had to take it back twice now because it souns like a diesel at start up. The noise does lessen after warm up but does not go away completely. I spoke to another customer from this shop and they had the same issue. Can anyone help?

  12. robert :

    Date: December 4, 2010 @ 2:48 pm

    I have a 02 jeep with a 4.7l when i got it had a dropped valve seat on the #2 intake valve. we replaced the head with a reman head and the first time it ran 500 miles before it dropped the #8 rocker so we got another head installed it and the same thing happeded on start up this time. I dont know if the head is been shaved too far or if there is a piston problem. any thoughts

  13. dennisb - Auto Tool Sales :

    Date: December 4, 2010 @ 4:16 pm

    I don’t see how the cylinder being shaved too much or why a piston issue would cause this problem.

    Usually the most likely cause of a rocker falling in this motor would be excessive carbon build up on the valve. We can eliminate that in this case since you’ve had two different heads do the same thing. (Obviously the remanufactured heads had new or at least different valve that came installed in them already.)

    Weak valve springs could also cause rocker arm falling as well. Again, this cannot be the problem since you tried two different heads, with different valve springs pre-installed.

    Oiling problems to the head, could be the cause. These 4.7 engines tend to sludge up easily if not kept full of oil and it changed regularly. Also upon first start up, it would take a little time for the oil to prime – it may take even longer for that cylinder if there’s some sludge present. Good Luck.

  14. LOU :

    Date: December 21, 2010 @ 9:55 pm

    Chrysler in Sydney Canada charged me $687.77 to fix my 2004 DAKOTA still under warranty-dec/10/2010. They said rocker arm out of place. Said possibly contaminated fuel, but left the same fuel in tank when it was a carbon build up and just got the run around. Milege on truck 6141. That’s the last for chrysler. I will BUY A
    FORD OR CHEV.

  15. dennisb - Auto Tool Sales :

    Date: December 22, 2010 @ 7:40 am

    Lou, that’s amazingly low miles. However, the warranty would be out due to the age of the vehicle – 3 year 36,000 miles. If you had a 2005, 2006 or 2007 there would have been a chance it would have been covered under the 7 year 70,000 mile drivetrain coverage. I understand your frustration with Chrysler (the 4.7 is actually a Mercedes design) but remember ALL manufacturers have certain problems – see the articles linked below for Ford and Chevy articles, covering some of their issues.

    Ford Problems

    Chevrolet Issues

  16. LOU :

    Date: December 22, 2010 @ 8:52 am

    dennisb. chrysler states this 2004
    DAKOTA,IS STILL UNDER WARRANTY until
    june 2011.thanks for reply.

  17. Garry Hoare :

    Date: February 3, 2011 @ 3:45 pm

    Hi, I have a 3.7 2004 liberty (cherokee in england), Ive had it 4+ years , it has just developed a mis fire, and is now running on only the near side 3 cylinders ,it had a crank sensor fault, but thats bin done, any idea`s guys …….
    Cheers Garry

  18. dennisb - Auto Tool Sales :

    Date: February 3, 2011 @ 8:08 pm

    Gary, the 3.7 and 3.9 V-6 engines shake like crazy even if there’s no misfires. You don’t mention misfire codes. With any OBD II vehicle, that’s the first thing to check for. Then check the basics, coil, injector pulse, spark plugs… compression also if needed. Good Luck

  19. Shadetree :

    Date: February 7, 2011 @ 5:28 pm

    Hi every1. I’m working on an 04 Cherokee with a 4.7. Needed headgaskets replaced. When I pulled valve covers #4 exhaust valve rocker arm was lying in head. I continued with head gasket job removed heads and took to machine shop. They cleaned carbon off valve, reinstalled rocker arm and machined both heads. I put jeep back together. On first startup the same rocker arm came off. Any suggestions?

  20. dennisb - Auto Tool Sales :

    Date: February 8, 2011 @ 9:32 am

    Hey Shadetree, sounds like a very frustrating problem. I wonder about a weak lifter or restricted oil passage. We’ve had many customers buy the Miller tools from us and replace the lifters themselves.

  21. jeff :

    Date: December 13, 2014 @ 1:51 pm

    I have a 2004 ram 1500 with a 3.7 have tapping noise at higher rpms?

  22. dennisb - Auto Tool Sales :

    Date: December 13, 2014 @ 6:02 pm

    Jeff could be lack of oiling or valves. Usually with a lifter problem, the noise would go away at higher RPM’s. Good Luck.

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