5.7 failure

[D Reed]

Hey all, I have a 2011 Ram 1500 with the 5.7 HEMI. I bought this truck with 36k on the clock. I have all the receipts from faithful service work that was performed by his local dealer. The engine started to have a clacking noise on deceleration that started at about 50k. The noise would start when coming to a stop and would stop like a switch when the speed hit 10 mph or so. Also I noticed it would not make this noise when in tow mode, ( that disables the MDS system.)

Well the truck has always run great, had the oil changed with Mobile 1 every 5k. and the noise never got any worse. Fast forward to 87,000 miles and the noise has gotten worse all of a sudden. When cruising down the road on "tip in", the engine will make a noise like it spun a rod bearing. The noise lasts about 3 seconds then stops. It will not make the noise in Tow Mode.

So now I have about 88,000 miles on the truck and I have developed a skip on cylinder 2. Now, I am 51 years old and I am an ASE, and Ford certified Technician with over 30 years experience. This skip starts when I get the RPMs up to about 3k and then it will skip real bad, then if I go real easy on the throttle the skip will totally go away and run perfectly. It wont skip again until I take off quickly and run it up to 3k.

Well this weekend I decided to pull the cam and lifters and low and behold, I found the lobe on #2 totally smoked. I found the lifter spun sideways in the plastic holder and wore out the cam. The roller was not frozen either. Why didn't this thing skip all the time? I don't get it. Does it have something to do with the MDS lifter set up? ( I have the MDS turned off with a tuner)

Well I installed the new cam and lifters this past weekend. It took about 20 hours and it runs great!

Just don't understand why it didn't skip all the time, if this was a regular engine like a small block Chevy or Ford it would have skipped like crazy and popped through the intake.

 

[Random_Walk]

Question (asked in total ignorance) - did the 2011 models not have a 6yr/60k powertrain warranty?

Congrats on finding/fixing the issue though... that's gotta be a bear to tear into and replace.

 

[blackbetty14]

When you loose a cam lobe the engine doesn’t really notice it till mid and high rpms or it doesn’t become noticeable to you until those rpms. When the rpm is high enough and a loss of power aka a dead cylinder becomes apparent.

Besides that the stock PCM has a pretty large tuning window and it can cover up some pretty serious leaks in the exhaust or vacuum side.

The lifter could have also dislodged from the plastic tray and reorientated itself and could have done it again (maybe why it went away for a while).

I think the bigger picture is your lucky the metal didn’t take out the bearings/motor and this prob could have been found a lot sooner if you cut the oil filters open during 30k of oil changes that you performed (5k changes means 6 chances you could have spotted metal in the filter).

 

[TXCOMT]

Congrats on finding/fixing the issue though... that's gotta be a bear to tear into and replace.

Amen...now that's a true tech! Do you live in North Texas? I could use a new best friend with your special set of skills!

TXCOMT

 

[Burla]

m1 5w20?

 

[D Reed]

BlackBerry I think your correct in saying the ecm probably masked it with fuel trims. I can remember doing worn cams back in the 80s and they skipped bad all the time with worn lobes. No pcm to adjust fuel

 

[D Reed]

Amen...now that's a true tech! Do you live in North Texas? I could use a new best friend with your special set of skills!

TXCOMT

Live in Western Ma

 

[Hemi_Express2013]

You know, I've become a firm believer in opening up the oil filters, burla, that's a new thread. The pcm can mask a lot of issues till all the damage is great enough, then you are in for a new motor. It seems once the lifters move in there plastic retainers, if your not inspecting the oil filters, game over!