Three rocker arms thrown out on 2015 5.7L 113k miles

Thursday when I started up the engine, it was made a ticking noise and the check engine light blinked on and off. This did not sound good. I drove slowly to the nearest garage about 5 miles away.

The mechanic put the computer on the engine and it was misfiring on one cylinder. They tried replacing the coil and spark plug for that cylinder but that did not fix the issue.

They pulled the valve cover off and found that 3 rocker arms were thrown out, CAM shaft has damage, cannot find one of the spacers, it's probably in the bottom of the oil pan.

Mechanic recommends installing a new cylinder head.

My question is, why at 113k miles did this happen?

I bought the truck as a Certified Pre-Owned vehicle from a dealer. It had around 60k miles. Since purchase I've had oil changes every 5000 miles.

A few months after I bought the truck, the dealer did the cam tower oil leak repair (at no charge) - installing proper gaskets on both sides.

Will the cylinder head replacement fix the issue? Is the other cylinder head likely to throw rocker arms as well?

 

I don't think this is a widespread problem with the 5.7's. There have been some here that have had them fail as well, but I don't know if anyone has pinpointed the reason for the failure. Did your mechanic explain why he wanted to replace the head on the side that failed?

 

@07DCLimited had to google what is a valvetrain! Thanks for the response. Looks like I need to talk with the dealer.

 

@TILLY Mechanic does not have an idea why it happened. Though I need to tell him about the cam tower work, which could provide a clue.

He wants to replace the head as it is about the same cost to replace the head as to do the work to repair the existing head, and there is damage to the cam shaft.

 

That sounds reasonable to me. Tell him about the cam tower work you had done, and have him recheck all the Rocker/Followers on the other side before he buttons it up. Hopefully this will be the last time you'll have to deal with this. Good luck.

 

@TILLY yes, that makes sense. Will talk with him on Monday about the other side

 

Wow! First I’ve heard of this so I did a quick Google search and you’re definitely not the first… That doesn’t instill confidence. I sometimes let my truck sit for a week to two weeks at a time. I hope this doesn’t happen to me. Good luck with the repair!

 

@7DCLimited hahaha!

 

Broken valve springs have been an issue for several manufacturers. I’ve read of some Toyotas having the issue in the 5.7. Dodge and GM have also had issues. I think the real culprit here is shitty steel. Poor materials to make the parts with. Valve springs get a lot of cycles.

 

Likely the culprit......... Dealer goofed something up when they did the cam tower gaskets. Anything is possible if they didn't get it right.

Does the Tundra even have rocker arms???!!! I would think NO, it is a top mounted camshaft with a follower (lifter) that pushes down on the valve......

I do NOT see rocker arms......... Cam over follower (lifter), though it looks like there may be a short rocker under the camshaft.

 

The cam lobes ride on small rollers below the cam. I guess they are considered rockers/followers.


Edit:
After re-reading the OPs post, is the mechanic sure it it isn't a broken valve spring? That's what cooked the engine in the YouTube video I clipped above. Did it drop any of the valves into the cylinder? That could mean more than a new head.

How long ago was the cam tower work done? If it was 50k miles ago, hard to blame that as the cause.

Edit again: do our trucks not have cam bearings?

 

@Retroboy1989 Yes! that guy @IDoCarsalldaylong does great teardown videos! https://www.youtube.com/watch?v=l_1zeSsoOK0

 

He is no Davin with Hagerty Redline Rebuilds, but it was ok.

 

@Retroboy1989 Davin is in a different class for sure.



Toyota is saying that they do not warranty repairs beyond 1 year. So it's tough luck. Oh well, at least the local garage is excellent.

 

Good that you have a trustworthy shop to help with these repairs. Did they find any broken valve springs?

 

What retains those things? Sounds like the cam got chewed up by the failure?

 

Given the repair history I’d suspect the cam tower/ cam structure was loose.

also can happen with roller follower bearings failing, broke valve spring, low oil pressure and even high oil pressure.

 

@blanchard7684 right. I talked with the Service Manager at a nearby well regarded Toyota dealer (not the dealer that did the work on the cam tower). I asked him what he would do if this were his truck, he said get the cylinder head replaced on the one side, pull the valve cover off the other side and make sure everything was torqued down properly. So he essentially agrees that the probable cause is improperly torqued components after the repair.

 

The cam retains them. I replaced a bad cam follower on my daughters 3.2 Jeep Cherokee. They are notorious, the “Pentastar tick”. Was a really easy job thankfully due to which one failed. The needle bearings in the roller on the cam follower disintegrate on those. Then the cam sees wear due to the cam follower, well, not following.

 

(nervously watches his 2015 that is approaching 113k .... but no tower repairs!)

 

A competent mechanic that doesn’t cut corners can handle a job like that with no issue. I have a buddy that works on high end European and Japanese cars who I trust with my life. Where you at in the North? I’m from central NY, if you’re in the area I can refer you to him.