Toyota 2ZZ-GE intake cam wear, car #2

[ProbeGT]

In late 2021 I discovered a wiped intake camshaft on one of my 2ZZ-GE equipped Pontiac Vibe GTs. https://bobistheoilguy.com/forums/t...intake-cam-wear-bad-oil-or-bad-filter.348741/ . I replaced the intake camshaft and 4 rocker arms and adjusted valve lash. After extensive research, I concluded that the root cause was inadequate ZDDP content in API 5W-30 oils used (SM, SN, SP). The car calls for 5w-30 API SL.

FFWD to now, I'm doing the same job on my other Vibe GT. This intake camshaft is again wiped although it's not quite as bad as it was on car #1. This car wasn't driven as hard. As was the case with the 1st car, the exhaust camshaft is perfectly fine and all cam journals and cam caps are in excellent shape. The difference this time around is that on the 2nd car, all intake valve clearances were prefectly in spec, 0.13mm on all 4 cylinders (spec is 0.08-0.18 mm). This is a confirmation that valve clearances are not the issue. API 5W30 oil was the problem all along after the arbitrary 800 PPM ZDDP limit was imposed with API SM.

I switched to high ZDDP 0W40 oils in both cars back in 2021. In these high-revving engines, there's no substitute for proper levels of ZDDP (over 1000 PPM). Higher viscosity also helps keep the cam lobes lubricated at RPMs over 8,000. For track use, I'd go up to xW50 or xW60 as some owners already do.

 

[tig1]

I haven't had that problem in this engine. My 2007 Ford fusion with 328K. This pic was about 2-3 weeks ago.

 

[ProbeGT]

I haven't had that problem in this engine. My 2007 Ford fusion with 328K. This pic was about 2-3 weeks ago.

This issue is specific to the Toyota 2ZZ-GE engine used in Lotus Elise, Toyota Celica GTS, Toyota Corolla/Matrix XRS and Pontiac Vibe GT. This engine, developed by Yamaha, revs up to 8,600 RPM and utilizes VVTL-i (similar to VTEC) with dual cam lobes. The high profile cam lobe rides on a slipper pad (not roller) and is under high stress at high RPM, requiring high anti-wear lubrication.

Most engine designs, yours included, do not rev that high and are not affected.

 

[tig1]

This issue is specific to the Toyota 2ZZ-GE engine used in Lotus Elise, Toyota Celica GTS, Toyota Corolla/Matrix XRS and Pontiac Vibe GT. This engine, developed by Yamaha, revs up to 8,600 RPM and utilizes VVTL-i (similar to VTEC) with dual cam lobes. The high profile cam lobe rides on a slipper pad (not roller) and is under high stress at high RPM, requiring high anti-wear lubrication.

Most engine designs, yours included, do not rev that high and are not affected.

Truly. That's why I select engines in my cars that are designed for the long haul. Can the higher ZDDP effect the cats?

 

[OilStainedNapkin]

I haven't had that problem in this engine. My 2007 Ford fusion with 328K. This pic was about 2-3 weeks ago.

View attachment 267474

Truly….a result of 10k mile ocis on mobil 1 for over 40 years, truly

 

[ProbeGT]

Truly. That's why I select engines in my cars that are designed for the long haul. Can the higher ZDDP effect the cats?

0W40, 5W40, 10w40, 15W40 oiis and higher viscosities are NOT subject to any ZDDP limits and yet we're not seeing any widespread cat failures. IMO the "cat card" was just an excuse to force the ZDDP reduction in lower viscosity oils because of false environmental agenda.

In any case, I have had zero issues with running 0W40 oil with up to 1,400 PPM ZDDP (Zinc and Phosphorus). Still running original cats, no CEL codes.

 

[slacktide_bitog]

It doesn't look that bad, and it probably isn't really that much of a problem, especially since most of them will rust before the cam can ever wear enough for anything bad to happen, and of course, the odometer stops at 299999 anyway

M1 0w40 seems like a good choice for the 2ZZ, and that same oil is widely used on the track as well.

For those who want to stay with a 30, there are probably some higher ZDDP oils in 5w30 and 0w30, such as RP HMX or HPS, Redline, VR1, Amsoil, and others.

This issue is specific to the Toyota 2ZZ-GE engine used in Lotus Elise, Toyota Celica GTS, Toyota Corolla/Matrix XRS and Pontiac Vibe GT. This engine, developed by Yamaha, revs up to 8,600 RPM and utilizes VVTL-i (similar to VTEC) with dual cam lobes. The high profile cam lobe rides on a slipper pad (not roller) and is under high stress at high RPM, requiring high anti-wear lubrication.

Most engine designs, yours included, do not rev that high and are not affected.

Do Hondas have these kinds of problems? Does a K20 from an RSX Type-S or Civic Si have that kind of wear? Or the S2000's F20C? They also go above 8000 rpm

 

[ProbeGT]

It doesn't look that bad, and it probably isn't really that much of a problem, especially since most of them will rust before the cam can ever wear enough for anything bad to happen, and of course, the odometer stops at 299999 anyway

I only have 132K on the ODO so a new camshaft and a set of new rocker arms is worth doing. Got the whole OEM kit from Toyota for $300. Plus about $80 for a set of new valve shims and a many hours of my free labor

M1 0w40 seems like a good choice for the 2ZZ, and that same oil is widely used on the track as well.
For those who want to stay with a 30, there are probably some higher ZDDP oils in 5w30 and 0w30, such as RP HMX or HPS, Redline, VR1, Amsoil, and others.

Currently running Castrol 0W40 in car1 and Amazon Basics 0W40 in car2. I like the AB due to it's 1,250 PPM ZDDP. I have a big stash of M1 0W40 and 5W40 from Walmart clearance and a huge stash of AB from Amazon clearance. Will stick with AB in car2 and start using M1 in car1. Let's see how they compare 50k miles later!

Do Hondas have these kinds of problems? Does a K20 from an RSX Type-S or Civic Si have that kind of wear? Or the S2000's F20C? They also go above 8000 rpm

Honda's VTEC uses rollers on both low and high cam lobes. Toyota's VVTL-i uses a roller on the low cam lobes but a slipper pad on the high cam lobes. That's where the wear occurs. I will admit that VTEC is a superior design compared to Toyota's VVTL-i, even though I'm a Toyota fan at heart.

Pictured below, Toyota rocker arm, slipper goes against high cam lobe, roller goes against low cam lobe. Worn part on left, new part on right. Below that, a Honda K20/K24 rocker arm assembly...all rollers. Better.

Toyota:

Honda:

 

[Cujet]

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 turbo, which was never designed to operate on such oil. The S2000 engine is tough, and well known for tolerating just about anything. But after years of issues racing and running lower viscosity oils, and two Honda water pump engine failures on the 'required' oil, I started to understand that here in FL temp matters. A lot.

My current car, the F-Type with AJ-126 engine has known shortcomings. Despite being designed for 0W-20 cam, chain and bearing issues are popping up. Jag DLC coated the cam followers (shims and buckets) to ensure they don't wear out quickly with the uber thin oil. But guess what happens? The DLC wears through. No amount of magic additive fixes this. Viscosity does.

Note: I'm not at all convinced ZDDP, moly or Ti additives do anything when cam components are DLC coated.

 

[Cujet]

I'd also like to add that it is my opinion that a wide viscosity spread oil, such as 0W-30/40, may also not be the correct way to achieve adequate viscosity for highly loaded parts. A subject of extensive discussion here on BITOG, with many posters correctly noting there are different quality VII's and shear rates vary between engines, uses and formulations.

Again, here we are often starting with a very low viscosity oil and bolstering it with additives to ensure it performs 'like' something else. Hoping we get the same protection as a 'straight 40'. Time after time, this is shown to be wrong.

With the level of wear you are seeing, a 'slight change' is not likely to be adequate.

 

[twX]

ZDDP breaks down over an OCI and eventually stops being effective. You've been doing 9k mile OCIs. Based on the all the varnish and evidence of sludge, this was too long.

Here's a figure from a study done by Toyota using a 5S-FE engine with flat tappets (SAE 2000-01-2053). After 5,000 km, remaining ZDDP drops to 20% (200 ppm P) and friction increases a lot. MoDTC degraded almost as quickly.

Flat tappet cams run hot due to friction. More friction means hotter and thinner oil films, which would probably result in more wear even if there was still enough ZDDP to form a protective film, which there probably isn't.

 

[ProbeGT]

ZDDP breaks down over an OCI and eventually stops being effective. You've been doing 9k mile OCIs. Based on the all the varnish and evidence of sludge, this was too long.

Since I discovered the high cam wear in 2021, I have been doing oil changes every 4,000-4,500 miles, using only fully synthetic xW-40 oils with high ZDDP content (as per VOA). There is some varnish but I saw no evidence of sludge in the 2nd car. As I mentioned, I inspected both intake and exhaust cams and all the cam caps. There is no evidence of wear on the exhaust camshaft, none. On the intake camshaft, the low lobes are perfectly smooth, only the high lobes have wear. All cam caps are in excellent condition with minimal wear.

Here's a figure from a study done by Toyota using a 5S-FE engine with flat tappets (SAE 2000-01-2053). After 5,000 km, remaining ZDDP drops to 20% (200 ppm P) and friction increases a lot. MoDTC degraded almost as quickly.

Interesting. This contradicts hundres of UOAs that do not suggest such a drastic drop in the amount of Zn and P remaining in used oil. I wonder who's right. One thing to remember is that the 2ZZ-GE engine is not a true flat-tappet engine. Based on my driving style, 98% of the time the cams run on rollers on the low profile lobes at RPMs under 6,200. So the depletion of ZDDP will be nowhere near Toyota's torture test. Still, based on this data, I will consider reducing OCI even further to 3,000 miles. I have a big oil stash so it won't cost me anything. Just the cost of the filters.

Flat tappet cams run hot due to friction. More friction means hotter and thinner oil films, which would probably result in more wear even if there was still enough ZDDP to form a protective film, which there probably isn't.

This is probably true. Hence the switch to higher viscosity in addition to using oil with higher ZDDP content.

 

[twX]

This contradicts hundres of UOAs that do not suggest such a drastic drop in the amount of Zn and P remaining in used oil. I wonder who's right.

When ZDDP breaks down, the elemental Zn and P will stay in the oil and so it will make no difference on a UOA. The study used more a advanced measurement technique.

Based on my driving style, 98% of the time the cams run on rollers on the low profile lobes at RPMs under 6,200. So the depletion of ZDDP will be nowhere near Toyota's torture test.

ZDDP will still break down even if it's not actively being used in an anti-wear role. It's an anti-oxidant and will break down while performing that function. I don't know how much faster it would deplete in a flat tappet engine, but it might not make a huge difference.

 

[Blinker]

This sounds like a Toyota problem. You even switched to what you thought was a more appropriate oil high ZDDP 0W-40 and it still wiped out the cam…

 

[JAG]

The shear rates in the valvetrain can significantly exceed 1e6/s, so there is a large temporary loss of viscosity in oils with a large amount of VIIs. Even using HTHS doesn't give a great indication of the viscosity there, though it is better than using kinematic viscosity. High base oil viscosity matters a lot. 0W-40 is a grade I would generally avoid in such a situation, along with 5W-50, and 10W-60.

 

[ProbeGT]

This sounds like a Toyota problem. You even switched to what you thought was a more appropriate oil high ZDDP 0W-40 and it still wiped out the cam…

That's inacurrate. Both cars ran 5W30 for the first 110K miles until 2021. The camshafts were already wiped from that oil. I fixed car1 back in 2021 but didn't get to car2 until now.

 

[BMWTurboDzl]

ZDDP breaks down over an OCI and eventually stops being effective. You've been doing 9k mile OCIs. Based on the all the varnish and evidence of sludge, this was too long.

Here's a figure from a study done by Toyota using a 5S-FE engine with flat tappets (SAE 2000-01-2053). After 5,000 km, remaining ZDDP drops to 20% (200 ppm P) and friction increases a lot. MoDTC degraded almost as quickly.

Flat tappet cams run hot due to friction. More friction means hotter and thinner oil films, which would probably result in more wear even if there was still enough ZDDP to form a protective film, which there probably isn't.

View attachment 267517

Sulfur levels in todays fuels are significantly lower compared to the late 1990's- early 2000's. NVM that we don't know the specificity of the test itself to draw any conclusion as to relevance in real world operation.

 

[53' Stude]

This sounds like a Toyota problem. You even switched to what you thought was a more appropriate oil high ZDDP 0W-40 and it still wiped out the cam…

That’s a bold faded lie and you know better.

 

[OVERKILL]

Sulfur levels in todays fuels are significantly lower compared to the late 1990's- early 2000's. NVM that we don't know the specificity of the test itself to draw any conclusion as to relevance in real world operation.

Also, (lack of) phosphorous retention was a thing, which is why it's now tested for. 81% is the minimum required for API SP, there was no retention requirement back with API SL.

Also, just add the SAE's summary of the cited study, emphasis added:
The deterioration of the friction reducing properties of engine oils containing molybdenum dithiocarbamates (MoDTCs) in service was studied. A quantitative analysis of MoDTCs and zinc dithiophosphates (ZDTPs) remaining in aged oils revealed that ZDTPs were consumed faster than MoDTCs. The consumption rate of ZDTPs was slow in the presence of MoDTCs and peroxide-decomposing antioxidants. The frictional properties of aged oils were evaluated with a reciprocating friction tester (SRV tester). The friction coefficient measured with the SRV tester was correlated to the properties of the aged oils, such as the TAN increase, TBN, and concentration of remaining ZDTPs.

ZDDP decomposes under heat and pressure to produce a phosphate glass to protect surfaces from wear. This will of course reduce the amount of the ZDDP compound in the lubricant over time. We see similar behaviour with Boron, which is consumed over the course of an OCI, though with ZDDP, the liberated zinc stays in the lubricant and the phosphate glass, as it's sacrificed to prevent wear, also ends up back in the oil (which is why we do not see meaningful reductions in their elemental content in UOA's), while more of the compound reacts with the surface to keep the sacrificial layers in place.

The study noting that the consumption rate of ZDDP is slow when in the presence of moly reaffirms what we've discussed on here in the past RE: the synergistic relationship between moly and ZDDP, which work together to reduce wear.

 

[Lawnman23]

This issue is specific to the Toyota 2ZZ-GE engine used in Lotus Elise, Toyota Celica GTS, Toyota Corolla/Matrix XRS and Pontiac Vibe GT. This engine, developed by Yamaha, revs up to 8,600 RPM and utilizes VVTL-i (similar to VTEC) with dual cam lobes.

A Yamaha-designed, Toyota-manufactured Japanese engine in a Pontiac Vibe...

That's a wild pedigree

Cool engine though, never knew about it till now.