Pentastar cam opinions

[Fabulous50s]

I'm really just wondering if I can get away with changing all the roller rockers to the.....cough....updated design. And the cams will live. Wishful thinking. The rear cams are an engine out job.

As well as dealer has a special tool to hold sprockets so cams can be changed without messing with timing chain. Engine has to come out for timing chain which are known to be issue free.

 

[mattd]

You can change the cams with the chain and sprockets in place. There are holders you. An buy. Sets are cheap on Amazon, and work.

 

[SammyChevelleTypeS3]

A few thoughts from my (somewhat) educated opinion having worked in this industry for a few decades.

1. Hardening was better
2. Rollers used to be just a bushing, when they introduced needle bearings is when we started to see failures
3. ZDDP has to play a role here, our anemic oils don't play well with anything flat
4. Cam on bucket is so dead simple and has worked for 40 years. But hardness has to be correct, as well as proper orientation to encourage the bucket to rotate.
5. Rollers have nothing to do with RPM. It is really just a way to have a more aggressive lobe profile (performance) but I suspect Rollers are used to reduce friction and help CAFE to some extent.

Obviously none of that worked for me here....... typical Chrysler quality control....all over the place.

Think you are on to it with each one. One thru five.
Also: This lack of or poor quality control seen today is not just at Chrysler.
Poor manufacturing / design / parts + cheaper materials use all seem to be showing up more in manufacturing across the globe today.

 

[oilboy123]

Had no clue the Pentastar V-6 had these issues. I just did valve cover seals/coils/spark plugs. This being a new to me 2012 F150 3.7 Duratech. It has 207,000 miles, and the cam lobes looked really good. I was expecting worse.

If I was doing it I would be doing new cams and the works. But I would sure hope that the new parts won't put you in the same spot

I hope you get it figured out.

 

[OVERKILL]

Think you are on to it with each one. One thru five.
Also: This lack of or poor quality control seen today is not just at Chrysler.
Poor manufacturing / design / parts + cheaper materials use all seem to be showing up more in manufacturing across the globe today.

Yup, and it's not just roller applications either.

Post in thread 'Toyota 2ZZ-GE intake cam wear, car #2'

Mar 11, 2025

I'm sure ZDDP levels play a role, this is well known. But let's be honest here viscosity must do the majority of the job. Quite simply it keeps such parts apart. When we are down to relying on additives to ensure long component life, something is likely wrong with the entire system. Basic things like way too much mechanical load, viscosity too low, excessive oil temperatures, low oil flow rates and even poor metallurgy (KTM's forged dark chocolate camshafts, cough, cough).

There is a reason I move directly to M1, 15W-50 in my high performance turbocharged engines. Even my old Honda S2000...

• Cujet

• 

But yeah, given the lifter issues with all recent pushrod engines, that we never had back in the 80's and 90's, clearly something has changed. The old roller lifters would last forever, hell, we'd recycle them onto new, much more aggressive camshafts, without giving it a 2nd thought.

Like when FT cores began to come from overseas and people started blaming the oils, claiming they had "no zinc!", while even cams properly broken in and run on HDEO's were failing, I think we are seeing the same thing with the lifters, which is why it's affecting all marques.

 

[Exhaustgases]

A few thoughts from my (somewhat) educated opinion having worked in this industry for a few decades.

1. Hardening was better
2. Rollers used to be just a bushing, when they introduced needle bearings is when we started to see failures
3. ZDDP has to play a role here, our anemic oils don't play well with anything flat
4. Cam on bucket is so dead simple and has worked for 40 years. But hardness has to be correct, as well as proper orientation to encourage the bucket to rotate.
5. Rollers have nothing to do with RPM. It is really just a way to have a more aggressive lobe profile (performance) but I suspect Rollers are used to reduce friction and help CAFE to some extent.

Obviously none of that worked for me here....... typical Chrysler quality control....all over the place.

#1 Yes and materials as well, so absolutely nothing has been improved since those good old days.

#2 Needle bearings were used far back in the old days I will need to research it better.

#3 Aircraft oils have never had ZDDP, and there are mostly flat tappets in small AC engines.

#4 Mostly all very correct, I think though rollers were to fix the manufactures lack of how to make flat lifters work, unlike Lexus that had if figured out.
#5 Oops, I included some of #5 in the #4 line. RPM, my comment on that is just an observation of the engines that seem to have less trouble with the roller tappets.

 

[Exhaustgases]

No cam is hard enough to shrug off roller skidding from a failed needle bearing.

You’ll never see needle bearings in the roller of industrial engines, it is ALWAYS a bushing. You can probably guess why that is.

Yeah if memory is correct the ones used(for industrial engines) were not very small, but they have been used. I will have to research this better and post examples.

 

[OVERKILL]

#4 Mostly all very correct, I think though rollers were to fix the manufactures lack of how to make flat lifters work, unlike Lexus that had if figured out.

Rollers were used to:
1. Reduce friction
2. Enable more diverse lobe profiles with steeper ramps

#5 Oops, I included some of #5 in the #4 line. RPM, my comment on that is just an observation of the engines that seem to have less trouble with the roller tappets.

Cummins ISX:

RPM is not a factor. The old roller Windsors spun much higher than 3K and never had problems. The early HEMI's, before VCT, also didn't have lifter problems.

 

[Exhaustgases]

Good pics, so are those needle bearings on the ISX?

Flat lifters and or buckets, versus the modern roller lifter garbage of now?
The picts from OVERKILL posted above, and the ones in this link what ya think? Oh and there are more under cover flat tappet pics on this site as well, with much higher mileage.

N

Thread '2007 Mazda 2.3 Under Valve cover pics'

Mar 23, 2025

Changed the valve cover gasket on my 2007 Mazda 3 2.3 today. Car has 157k on it, I'm almost certain it had a used engine swapped in at some point prior to my ownership. For the last 6 years 30k miles its gotten annual changes with 5w-30 (last few years its been Chevron Syn-Blend). Looking good to me. What do you all think? It will use roughly 1 qt over a year and 5-7k miles.

• nwjones18
• Replies: 11
• Forum: Mechanical/Maintenance Forum

• 

 

[Fabulous50s]

Found bad lobes on 2 out of the 4 cams on this V6. Exhaust on Left (front) bank, and intake on Right (back) bank. Changed all lash adjusters and roller rockers associated with those cams. $1600 in parts, and all in stock at my local dealer.

I've worked on many many OHC engines with buckets and it surely is rare to see a cam failure which is not associated with lack or lubrication.

Here is a pic from a thread I posted about my wife's Honda which burned a valve at 176k due to carbon holding it open. No perceived valve train wear.

 

[OVERKILL]

Good pics, so are those needle bearings on the ISX?

Flat lifters and or buckets, versus the modern roller lifter garbage of now?
The picts from OVERKILL posted above, and the ones in this link what ya think? Oh and there are more under cover flat tappet pics on this site as well, with much higher mileage.

N

Thread '2007 Mazda 2.3 Under Valve cover pics'

Mar 23, 2025

Changed the valve cover gasket on my 2007 Mazda 3 2.3 today. Car has 157k on it, I'm almost certain it had a used engine swapped in at some point prior to my ownership. For the last 6 years 30k miles its gotten annual changes with 5w-30 (last few years its been Chevron Syn-Blend). Looking good to me. What do you all think? It will use roughly 1 qt over a year and 5-7k miles.

• nwjones18
• Replies: 11
• Forum: Mechanical/Maintenance Forum

• 

I'm actually surprised we don't see more pictures of failed buckets and worn FT cams on here (you can find them, but everybody seems to be moving toward or is already roller). Roller cams/lifters SHOULD last basically forever, which they used to, so it's a rather scathing inditement of the state of the industry that pretty much every major manufacturer has been touched by a problem that historically, wasn't one, before the outsourcing and overseas offshoring bonanza.

 

[tiger862]

Someone needs to figure out how to install a bushing where needle bears are and patient it. I can tell you I would purchase them when mine fails. Heck I might even change them out to save cams. Lol