Which Failed First? Cam, Lifter, or Guide

[Zpeedstr]

2014 Ram 5.7 Hemi with 150K miles. Always Mobil1 every 5K miles.
Cam and Lifter and Guide failed. Which failed first?
The cam is grooved by the roller with the lifter rotated 90 degrees. The lifter roller still rolls. The plastic guide cracked. The crack might be the failure mode or the result of the lifter rotating. The lifter is MDS and the MDS activation pin is rotated inside the lifter and not functional. The cam lobe might have worn down first causing the failure.

 

[J-13GTP]

Its been said that the pins in the roller go first. Ive also read that there has been a forging issue with cams that caused their hardness to be an issue. Some also say that its design is the failure point. With the cam sitting higher in the block, lubrication becomes a problem which then leads to the failures seen. I think its combination as a whole.

 

[QwikKota]

Is that plastic guide all the keeps the lifter from rotating in the bore?

 

[Wild one]

Is that plastic guide all the keeps the lifter from rotating in the bore?

Yes

 

[QwikKota]

Yes

That raises a lot of eyebrows but I imagine it has something to do with allowing the roller to find it's natural path on the lobe and not over constraining the alignment which could cause excess wear. Still dumb though, hah.

 

[Hemi_Guy]

2014 Ram 5.7 Hemi with 150K miles. Always Mobil1 every 5K miles.
Cam and Lifter and Guide failed. Which failed first?
The cam is grooved by the roller with the lifter rotated 90 degrees. The lifter roller still rolls. The plastic guide cracked. The crack might be the failure mode or the result of the lifter rotating. The lifter is MDS and the MDS activation pin is rotated inside the lifter and not functional. The cam lobe might have worn down first causing the failure. View attachment 565975View attachment 565976

You know with all these (including mine) cam and lifters being replaced on these Rams. Seems like a class action lawsuit should be filed.

 

[hangover101]

It would help if they had pressurized oil around the lifter body. MDS delete lifters .060 hole in the solenoid block off plugs between the O rings

 

[Wild one]

You know with all these (including mine) cam and lifters being replaced on these Rams. Seems like a class action lawsuit should be filed.

There was,and it didn't turn out the way we wanted. Search my name,i posted a video on it a couple days ago.