Cold start engine wear?

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If the statement that" most engine wear occurs at startup" is true , shouldn't we run lower viscosity winter weight oils if your diesel is in a cold environment at startup? I know there are engineers and motor head guys here and I am curious about your thoughts.
 
In a couple more years I should have a few more UOA under my belt to show how semi synthetic 10w30 works year round in my ISB6.7. I only have 2 so far on a relatively fresh engine.
 
. The cold and warmup phase increased wear is much more than just the oil. We have 5W and 0W-XX oils on the market now. Cold start and warm up wear is caused by fuel wash down in the cylinders due to less than ideal combustion. The pistons are oval when cold, measure them so there is more blow by washng the oil from the cyl walls. The metals have not expanded from the heat so the engine is looser. Looser equals more wear etc. Also some of the additive package elements workbest when hot.
 
Your numbers would be important living in Canada.Look forward to seeing them.I presume it gets hotter in Kansas in summer. That 30 number has me concerned for August. My tractor is an hst and I run it at about 2000 rpm .In alot of ways it operates like a gen set.
 
Originally Posted by Rglossip
If the statement that" most engine wear occurs at startup" is true , shouldn't we run lower viscosity winter weight oils if your diesel is in a cold environment at startup? I know there are engineers and motor head guys here and I am curious about your thoughts.

All oil is very thick when not at the operating temperature. There is no wear issue with any winter grade oil unless it is so very cold that the oil gels and cannot flow to the pump pickup tube. A 0W, or a 5W or a 10W or a 15W rated oil at startup will not affect wear. An oil with a better winter rating is not "thin".

Having said that, you do not reduce wear with thinner oils. You decrease fuel consumption with them, and if cold and you make it easier for the engine to start.
 
Definitely didn't know that.I can plug my tractor in.From that perspective that will help alot.
 
I think we tend to blow the cold start up wear out of proportion here. Modern oils and improved engine designs and fuel management protect engines a lot better against cold start wear than they did a few decades ago. Yes there is more wear when an engine first starts, but it isn't like the engine is grinding itself away every morning when you fire it up. Case in point, when I started driving, a car with 100K was considered pretty much done or due for a some engine work. Engines today can easily double or triple that without any major engine work.
 
Originally Posted by rideahorse
Shouldn't be an engine in North America or Canada running if you believe that cold starts ruin engines.

Canada is in North America.
 
Is that in Merica?
Originally Posted by benhen77
Originally Posted by rideahorse
Shouldn't be an engine in North America or Canada running if you believe that cold starts ruin engines.

Canada is in North America.
 
Originally Posted by benhen77
Originally Posted by rideahorse
Shouldn't be an engine in North America or Canada running if you believe that cold starts ruin engines.

Canada is in North America.



Canada puts the North in North America lol.
 
Originally Posted by Rglossip
If the statement that" most engine wear occurs at startup" is true , shouldn't we run lower viscosity winter weight oils if your diesel is in a cold environment at startup? I know there are engineers and motor head guys here and I am curious about your thoughts.
Engineers at Toyota, Mazda, Ford, Subaru, GM, BMW-Mini, Mercedes, Jaguar, and VW-Audi say to use 0w20 in a lot of their engines. They like the "0w" part, and they think the "20" part is OK. They would recommend 10w-30 if they didn't like 0w and 20 so much. --------- Side with them on the issue, as they have studied it a lot. --- Maybe they are afraid of warranty claims when somebody starts up at -20 F. Above zero F, there seems to be little reason to have the 0w cold rating part (could be 5w).
 
Originally Posted by paoester
Originally Posted by Rglossip
If the statement that" most engine wear occurs at startup" is true , shouldn't we run lower viscosity winter weight oils if your diesel is in a cold environment at startup? I know there are engineers and motor head guys here and I am curious about your thoughts.
Engineers at Toyota, Mazda, Ford, Subaru, GM, BMW-Mini, Mercedes, Jaguar, and VW-Audi say to use 0w20 in a lot of their engines. They like the "0w" part, and they think the "20" part is OK. They would recommend 10w-30 if they didn't like 0w and 20 so much. --------- Side with them on the issue, as they have studied it a lot. --- Maybe they are afraid of warranty claims when somebody starts up at -20 F. Above zero F, there seems to be little reason to have the 0w cold rating part (could be 5w).


Exactly. I don't know why people continually think they can outsmart the people that built the engines.
 
Originally Posted by paoester
Originally Posted by Rglossip
If the statement that" most engine wear occurs at startup" is true , shouldn't we run lower viscosity winter weight oils if your diesel is in a cold environment at startup? I know there are engineers and motor head guys here and I am curious about your thoughts.
Engineers at Toyota, Mazda, Ford, Subaru, GM, BMW-Mini, Mercedes, Jaguar, and VW-Audi say to use 0w20 in a lot of their engines. They like the "0w" part, and they think the "20" part is OK. They would recommend 10w-30 if they didn't like 0w and 20 so much. --------- Side with them on the issue, as they have studied it a lot. --- Maybe they are afraid of warranty claims when somebody starts up at -20 F. Above zero F, there seems to be little reason to have the 0w cold rating part (could be 5w).

Maybe the engineers bosses also like the money the company gets paid from CAFE credits that the 16 and 20 grade oils give in the form of slight fuel savings over a 30 or 40 grade oil. FTR 5W30 is recommended more than 10W30, it has been that way for several years now.
 
Sure it's a balancing act with some factors we don't even know about.
I'm happy to run it to end of warranty and think about something else then.
 
The whole topic of high wear at start up is total bunk in today's engines.
Macro data shows it's an overblown topic. There's zero proof that it's an issue, and actually hasn't been for many, many years.
There are short-trip commuters that see lots of cold start cycles and they might have 5x the starts that my car sees (I typically only start it 2x a day; once in to work and once home - 30 miles each way).
Are their wear rates 5x mine? No way in Hades.

We had an 1995 Villager back in the day; got it new and ran it to 245k miles. Ran UOA experiments on it trying to understand how OCI duration and use affect wear. It was the wife's van and when the kids were young it was the perfect example of the quintessential soccer mom ride. Short trips, lots of cold starts, etc. It should have been the perfect example of high-wear, if you believe the oil companies and the owner's manual (3k miles for "severe" service were the recommendation). I wanted to experiment, though ... actually started moving out to 5k mile OCIs; no resulting wear issues. Then 10k miles; still no wear issues. Ran some 15k mile OCIs; again no issues. The wear rates were coming down as the OCIs went up. And ... We would take it out to AZ from IN every other Thanksgiving to see the in-laws. Long hauls of 12 hours at steady state; often a 5k mile round trip with all the various side trips of sight seeing. Guess what ... ???
The wear rates never budged; they were what they were. Didn't matter than I ran longer OCIs. Didn't matter than we change operational patterns. The wear rates were fairly steady. There is always variation involved; things are not totally stagnant. But the amount of "normal" variation FAR exceeds the variation from the type of service factors typically induced in use. Life happens, and the engines generally don't care. They shed what they shed, and you're not typically doing much to alter it.

In all the macro data I have, there is zero proof that staring an engine repeatedly makes for a lot of wear. That might have been true 50 years ago when oils were not great and manufacturing of engines was not not great in terms of tolerance controls and machined surfaces. However engines made in the last few decades, as well as the improvements in lubrication, just make this a non-issue; it's a topic that is based in the same age-old rhetoric as is the 3k mile OCI.

If someone has proof (real world data that is not just hearsay) I'll entertain the conversation. But all the facts I have seen show it's a moot point. After all, I have over 15,000 UOAs from all manner of engines and applications; cars, trucks, tractors, generators, etc. Use in FL, AK, AL, CA, MN, ME, TX, AZ, etc. You name it, I've probably got a UOA that represents it well. And the data tells me that multiple starts does NOT induce a shift in wear rates that is discernible in the grand scheme of use. There are a few exceptions I have seen, but even the shift in wear is not enough to make a mountain out of the mole-hill. I've seen wear rates go up as much as 50%, but you have to keep that in perspective ... when an engine averages 2ppm/1k miles, then the use pattern shifts to 3ppm/1k miles, it's not like that engine is suddenly going to blow up, or fail in the next decade. Wear rates today are so low on most engines that even major shifts in wear (again, these are rare) still do not result in wear rates high enough to be of any concern whatsoever. Your car will either rot or be destroyed in a wreck far sooner than the engine will die from wear cause by start-up.
 
Originally Posted by dnewton3
The whole topic of high wear at start up is total bunk in today's engines.
Macro data shows it's an overblown topic. There's zero proof that it's an issue, and actually hasn't been for many, many years.
There are short-trip commuters that see lots of cold start cycles and they might have 5x the starts that my car sees (I typically only start it 2x a day; once in to work and once home - 30 miles each way).
Are their wear rates 5x mine? No way in Hades.

We had an 1995 Villager back in the day; got it new and ran it to 245k miles. Ran UOA experiments on it trying to understand how OCI duration and use affect wear. It was the wife's van and when the kids were young it was the perfect example of the quintessential soccer mom ride. Short trips, lots of cold starts, etc. It should have been the perfect example of high-wear, if you believe the oil companies and the owner's manual (3k miles for "severe" service were the recommendation). I wanted to experiment, though ... actually started moving out to 5k mile OCIs; no resulting wear issues. Then 10k miles; still no wear issues. Ran some 15k mile OCIs; again no issues. The wear rates were coming down as the OCIs went up. And ... We would take it out to AZ from IN every other Thanksgiving to see the in-laws. Long hauls of 12 hours at steady state; often a 5k mile round trip with all the various side trips of sight seeing. Guess what ... ???
The wear rates never budged; they were what they were. Didn't matter than I ran longer OCIs. Didn't matter than we change operational patterns. The wear rates were fairly steady. There is always variation involved; things are not totally stagnant. But the amount of "normal" variation FAR exceeds the variation from the type of service factors typically induced in use. Life happens, and the engines generally don't care. They shed what they shed, and you're not typically doing much to alter it.

In all the macro data I have, there is zero proof that staring an engine repeatedly makes for a lot of wear. That might have been true 50 years ago when oils were not great and manufacturing of engines was not not great in terms of tolerance controls and machined surfaces. However engines made in the last few decades, as well as the improvements in lubrication, just make this a non-issue; it's a topic that is based in the same age-old rhetoric as is the 3k mile OCI.

If someone has proof (real world data that is not just hearsay) I'll entertain the conversation. But all the facts I have seen show it's a moot point. After all, I have over 15,000 UOAs from all manner of engines and applications; cars, trucks, tractors, generators, etc. Use in FL, AK, AL, CA, MN, ME, TX, AZ, etc. You name it, I've probably got a UOA that represents it well. And the data tells me that multiple starts does NOT induce a shift in wear rates that is discernible in the grand scheme of use. There are a few exceptions I have seen, but even the shift in wear is not enough to make a mountain out of the mole-hill. I've seen wear rates go up as much as 50%, but you have to keep that in perspective ... when an engine averages 2ppm/1k miles, then the use pattern shifts to 3ppm/1k miles, it's not like that engine is suddenly going to blow up, or fail in the next decade. Wear rates today are so low on most engines that even major shifts in wear (again, these are rare) still do not result in wear rates high enough to be of any concern whatsoever. Your car will either rot or be destroyed in a wreck far sooner than the engine will die from wear cause by start-up.


thumbsup2.gif
I've said it a few times, startup wear gets blown way out of proportion here. With over 15K UOA's I'd say you have more than enough to prove your point.
 
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