What?! I just drive my vehicles. Sometimes I’m moving. Sometimes I’m idling. I’d never own something that couldn’t handle idling for 3 mins in drive-through line. These engines sound positively fragile if that’s what is required to keep them in good working order or this is way overkill.I think that’s the reasoning behind the MS-12633 2 year Vegas Taxi Cab Endurance test.
I don’t idle mine. I cut it off if it isn’t moving except at traffic lights. Drive thrus it’s cut off until I can move up or pull out.
And if it has sit for a couple of days without being driven, I prime it before starting.
But I’ve spent 2300.00 on repairs over 145,000 miles (keep in mind all the labor was me)…..I think that’s pretty good.
Might I also point out…. Look at the pictures I posed closely. Even the surface of the lobes that nothing contacts look pitted/galled. That’s why I’m not so sure is always a lifter as the root cause.
Definitely could be some materials quality with the cams/cores too, absolutely. I just know in terms of the bigger issue, most of the focus has been on the lifters, hence the multiple revisions.Might I also point out…. Look at the pictures I posed closely. Even the surface of the lobes that nothing contacts look pitted/galled. That’s why I’m not so sure is always a lifter as the root cause.
Assuming you still have the old lifters around, can you take them apart? Would be quite interested to see what the rollers, pins and needles look like, given your somewhat unique situation here.Obviously I can’t subject the roller to the same pressures it sees popping a valve open but I ran rollers from the perfect lobes and from the ones you saw and they were identical in smoothness and clearances as felt by hand. Without forensic examination, I can’t say any lifters failed.
I think I mentioned earlier I’ve been a dealer tech for years and have seen some carnage, especially the ones that were driven until they stopped.
The cams that fail also have some lobes that look like mine did without notable lifter failure on that lobe. I’ve also seen these same engines into the 200,000 range without failures. It’s still a debate.
So the consensus here is to stick with something in a Euro formula as in the Valvoline?
I mentioned that before, not sure if you meant me. Anyway, here is a pic....look close and u can see the pin is worn. It is NOT a roller problem, as in the little rollers....Once pin gets worn enough, with enough clearance, the small rollers jam/pile up, and the outside roller stops turning....game over fast. The marks u see on cam are just crappy surface hardening/treatment they use. Have seen that for years going back all the way to 88 or so on 2.2/2.5.....used to see it on them, on the roller cams. See it on other manu. also. They will go quite a while like that, but that said personally I wouldnt reuse it. And the 3.6 tick issue is the same thing, soft pin. Oil will NOT fix any of this.On the rollers, so you put pressure on them while rolling them slowly to feel for any rough spots? Since these wear patterns look to be on the top of the lobes, where pressure will be the highest, and not on the base circle (which is where skating would happen if that were a problem) it does point to either a breakdown of the surface hardening of the lobe itself, or the roller intermittently not rolling in that location.
A dealer tech posted on here in the past and indicated that the cause of failure is poor surface hardening in the pin or roller. The needle bearings begin to produce a small groove in either the centre pin, or the roller. This creates a spot where it can "stick", and this eventually gets larger and larger until it completely stops rolling, at which point the lobe gets wiped-out in short order, as does the roller.
Yup, pretty sure it was you Thanks for chiming in!I mentioned that before, not sure if you meant me. Anyway, here is a pic....look close and u can see the pin is worn. It is NOT a roller problem, as in the little rollers....Once pin gets worn enough, with enough clearance, the small rollers jam/pile up, and the outside roller stops turning....game over fast. The marks u see on cam are just crappy surface hardening/treatment they use. Have seen that for years going back all the way to 88 or so on 2.2/2.5.....used to see it on them, on the roller cams. See it on other manu. also. They will go quite a while like that, but that said personally I wouldnt reuse it. And the 3.6 tick issue is the same thing, soft pin. Oil will NOT fix any of this.
Nope. If anything, the MDS lifters have an easier life when they are just following the lobe and not having to open the valve.Any advantage in disabling MDS for lifter life. My friend has a afm disabler on his Chevrolet. He says it will reduce wear on lifters. Would that be the case on the 5.7/6.4 engines?
You'll never prevent the failure if it's the metallurgical issue that @TeamZero has posted on. If the hardening isn't right, eventually, it's going to fail, regardless of what you put in the pan and regardless of how frequently you change it. The lifters have been revised multiple times now due to this issue, but it really seems like it's just a materials/QC problem, and GM has the same problem, I assume from the same vendor. Hopefully 3rd time is the charm and they've got it sorted now?So the best way to try and prevent this is to maybe go a little earlier on the OCI?
Without personally examining the lobes, it looks like spall debris denting... meaning the dents came after the damaged lobe started shedding material. If this denting preceded lobe damage, then there was contamination that possibly interfered with proper needle roller operation in the lifters, causing skidding.Might I also point out…. Look at the pictures I posed closely. Even the surface of the lobes that nothing contacts look pitted/galled. That’s why I’m not so sure is always a lifter as the root cause.
I wouldn't change anything. The oil did its job. Hopefully new parts will last longer. Not an oil problem.I have a 300C with a 5.7. Surprisingly it’s one of the most reliable vehicles I’ve ever owned….besides my Tacoma (if it wasn’t for rust it WOULD last forever).
I recently turned 145,000 miles and looking at new cars (and used) I decided to keep the 300 and “freshen” it up because I love it so much.
The Achilles heel (cam failure) was really the only thing I was concerned with. I put a new OE cam, lifters, rockers and shafts, timing components, and had the heads re-done.
All the roller lifters were perfect, however I did see some lobe deterioration just starting. See pics.
I’ve used 5-w20 Castrol Edge since new. I’ve switched to the Penzoil (born from NG) because a few on here tell me Castrol has a ****ty base stock.
Does anyone recommend I add a friction modifier? My OCI is about 5-6000 miles. I do drive hard but a lot of highway.
If so, what’s the consensus on a good additive?
TIA
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In my limited new gen Hemi experience the cam metallurgy is very questionable.
I am rebuilding the 6.1 in my 300 and had similar but much lesser wear and damage in my cam and lifters. All the roller lifters seemed flawless, but the cam was wiped out on one lobe only. It had a strange nearly inaudible tap that was very irregular, we thought for sure it was the timing set! Mileage was about 120k.
I had the boyz at Howard's cams make me a new one properly, car is going back together by Christmas I hope!
How do you know cam metallurgy is very questionable? How do you know it's not something else like a lubrication issue or a lifter issue?In my limited new gen Hemi experience the cam metallurgy is very questionable.