Extended OCI Issues
- Thread starter Gebo
- Start date
- Status
It depends very heavily on the driving profile.
One cannot make generalizations based solely on miles.
When I still ran my car on long-trips for most of the time with very few cold starts, idle time etc. I extended my OCIs to 9,5k miles.
But now that I mainly do city-driving, I cut them to about 5-6k miles again.
A good value to go by is ~200 engine operating hours until you do an oil-change.
Using dino oil, I'd stick closer to the 100-150 hour mark.
Also there are some engines that can cope better with longer OCIs than others due to their construction.
One cannot make generalizations based solely on miles.
When I still ran my car on long-trips for most of the time with very few cold starts, idle time etc. I extended my OCIs to 9,5k miles.
But now that I mainly do city-driving, I cut them to about 5-6k miles again.
A good value to go by is ~200 engine operating hours until you do an oil-change.
Using dino oil, I'd stick closer to the 100-150 hour mark.
Also there are some engines that can cope better with longer OCIs than others due to their construction.
Last edited:
Originally Posted by DrDanger
So the Russian oil forum I go to says: Cheap group I oil is a seal conditioner/sweller.
Try adding a quart of cheap dino.
I kind of fixed a slight power-steering leek with a mineral Dex II, not 100%, but level stays on full.
They also see 1-2% of Group I (VOA spectroscopy) in Valvoline Maxlife, they bet its there for that seal conditioning. I kind of believe them on that one...
You make some very interesting points. Thank you!
I PM'd you.
So the Russian oil forum I go to says: Cheap group I oil is a seal conditioner/sweller.
Try adding a quart of cheap dino.
I kind of fixed a slight power-steering leek with a mineral Dex II, not 100%, but level stays on full.
They also see 1-2% of Group I (VOA spectroscopy) in Valvoline Maxlife, they bet its there for that seal conditioning. I kind of believe them on that one...
You make some very interesting points. Thank you!
I PM'd you.
Originally Posted by Gebo
You can see I try keep my cars for the duration. I only use OEM Toyota/Lexus parts and fluids (even brake fluid and batteries). For the majority of their lives (so far) my oils have varied from Amsoil to Redline to Schaeffers etc. Good oils with 5-10K OCI's.
My 4Runner and my '98 LS 400 started leaking oil from valve cover and cam seals and finally has progressed to staining the driveway.
I started listening to AGCO Podcasts and they are staunch proponents of 3K OCI. Here is a copy and paste from their website:
The most common cause of failure with valve cover gaskets is a lack of maintenance. With extended oil changes, we may deplete engine oil additives that help keep valve cover gaskets pliable.
Without this protection, gaskets and seals get hard and may start to leak.
What is your opinion of this statement? Are we being duped by our owner's manual instructions and our focus on oil analysis?
Greetings-
I read on this forum, just several days ago, modern seal materials are unaffected by any seal enhancers, additives. So, assuming this is true, the likely cause is simply old age. Things don't stay new or last forever.
You can see I try keep my cars for the duration. I only use OEM Toyota/Lexus parts and fluids (even brake fluid and batteries). For the majority of their lives (so far) my oils have varied from Amsoil to Redline to Schaeffers etc. Good oils with 5-10K OCI's.
My 4Runner and my '98 LS 400 started leaking oil from valve cover and cam seals and finally has progressed to staining the driveway.
I started listening to AGCO Podcasts and they are staunch proponents of 3K OCI. Here is a copy and paste from their website:
The most common cause of failure with valve cover gaskets is a lack of maintenance. With extended oil changes, we may deplete engine oil additives that help keep valve cover gaskets pliable.
Without this protection, gaskets and seals get hard and may start to leak.
What is your opinion of this statement? Are we being duped by our owner's manual instructions and our focus on oil analysis?
Greetings-
I read on this forum, just several days ago, modern seal materials are unaffected by any seal enhancers, additives. So, assuming this is true, the likely cause is simply old age. Things don't stay new or last forever.
Gebo.....Toyota/Lexus gaskets & seals harden & leak with age, Nothing to do with OCI.
Valve Cover gaskets & Cam seals are maintenance items on Timing Belt Toyotas! Be thankful you don't have a FIPG leak on a newer chain engine!!
Valve Cover gaskets & Cam seals are maintenance items on Timing Belt Toyotas! Be thankful you don't have a FIPG leak on a newer chain engine!!
Originally Posted by willbur
Originally Posted by Gebo
You can see I try keep my cars for the duration. I only use OEM Toyota/Lexus parts and fluids (even brake fluid and batteries). For the majority of their lives (so far) my oils have varied from Amsoil to Redline to Schaeffers etc. Good oils with 5-10K OCI's.
My 4Runner and my '98 LS 400 started leaking oil from valve cover and cam seals and finally has progressed to staining the driveway.
I started listening to AGCO Podcasts and they are staunch proponents of 3K OCI. Here is a copy and paste from their website:
The most common cause of failure with valve cover gaskets is a lack of maintenance. With extended oil changes, we may deplete engine oil additives that help keep valve cover gaskets pliable.
Without this protection, gaskets and seals get hard and may start to leak.
What is your opinion of this statement? Are we being duped by our owner's manual instructions and our focus on oil analysis?
Greetings-
I read on this forum, just several days ago, modern seal materials are unaffected by any seal enhancers, additives. So, assuming this is true, the likely cause is simply old age. Things don't stay new or last forever.
Well, if I may delicately add, I don't assume reading something on this forum makes it true. LOL
I do love most of the discussions and wide range of opinions.
Originally Posted by Gebo
You can see I try keep my cars for the duration. I only use OEM Toyota/Lexus parts and fluids (even brake fluid and batteries). For the majority of their lives (so far) my oils have varied from Amsoil to Redline to Schaeffers etc. Good oils with 5-10K OCI's.
My 4Runner and my '98 LS 400 started leaking oil from valve cover and cam seals and finally has progressed to staining the driveway.
I started listening to AGCO Podcasts and they are staunch proponents of 3K OCI. Here is a copy and paste from their website:
The most common cause of failure with valve cover gaskets is a lack of maintenance. With extended oil changes, we may deplete engine oil additives that help keep valve cover gaskets pliable.
Without this protection, gaskets and seals get hard and may start to leak.
What is your opinion of this statement? Are we being duped by our owner's manual instructions and our focus on oil analysis?
Greetings-
I read on this forum, just several days ago, modern seal materials are unaffected by any seal enhancers, additives. So, assuming this is true, the likely cause is simply old age. Things don't stay new or last forever.
Well, if I may delicately add, I don't assume reading something on this forum makes it true. LOL
I do love most of the discussions and wide range of opinions.
Hmm. 20 years is a long time. An oil change is what, $20 or so? So over 300k one could do 100 oil changes or 50; 50 times $20 is a grand. Seems like a valve cover gasket is less than a grand, so I wouldn't want to use a short OCI just to save on a VC gasket. But. A rear main seal could be more costly.
Of course, who keeps cars for 20 years?
What I don't get is why it's common for valve cover gaskets to go out, while oil pan gaskets don't seem to fail at the same rate. Higher heat? Or maybe I'm just wrong in that impression, maybe oil pan gaskets go out just as frequently.
Of course, who keeps cars for 20 years?
What I don't get is why it's common for valve cover gaskets to go out, while oil pan gaskets don't seem to fail at the same rate. Higher heat? Or maybe I'm just wrong in that impression, maybe oil pan gaskets go out just as frequently.
Originally Posted by willbur
So...the replies you read so far are true? But not the one I referenced? Why bother posting
Wilbur, I apologize. I didn't mean my post the way you took it. What I am trying to say is that I don't believe everything I read on this forum.
I believe you read what you said you read on this forum and I believe you when you said you assumed it was true.
That's why I am asking what you think of the "pink" sentences in my post.
I'm sorry. I want you to post your thoughts.
So...the replies you read so far are true? But not the one I referenced? Why bother posting
Wilbur, I apologize. I didn't mean my post the way you took it. What I am trying to say is that I don't believe everything I read on this forum.
I believe you read what you said you read on this forum and I believe you when you said you assumed it was true.
That's why I am asking what you think of the "pink" sentences in my post.
I'm sorry. I want you to post your thoughts.
Originally Posted by supton
Hmm. 20 years is a long time. An oil change is what, $20 or so? So over 300k one could do 100 oil changes or 50; 50 times $20 is a grand. Seems like a valve cover gasket is less than a grand, so I wouldn't want to use a short OCI just to save on a VC gasket. But. A rear main seal could be more costly.
Of course, who keeps cars for 20 years?
What I don't get is why it's common for valve cover gaskets to go out, while oil pan gaskets don't seem to fail at the same rate. Higher heat? Or maybe I'm just wrong in that impression, maybe oil pan gaskets go out just as frequently.
Cam seal replacement labor on my car is very expensive as well. They gotta remove the cams.
I plan on keeping most of my cars for 20 years. Til death do us part...
Hmm. 20 years is a long time. An oil change is what, $20 or so? So over 300k one could do 100 oil changes or 50; 50 times $20 is a grand. Seems like a valve cover gasket is less than a grand, so I wouldn't want to use a short OCI just to save on a VC gasket. But. A rear main seal could be more costly.
Of course, who keeps cars for 20 years?
What I don't get is why it's common for valve cover gaskets to go out, while oil pan gaskets don't seem to fail at the same rate. Higher heat? Or maybe I'm just wrong in that impression, maybe oil pan gaskets go out just as frequently.
Cam seal replacement labor on my car is very expensive as well. They gotta remove the cams.
I plan on keeping most of my cars for 20 years. Til death do us part...
Last edited:
I messed up my original post and once I saw it, I could not edit it.
Here is how my original post should have read. Nothing else should have been included:
I started listening to AGCO Podcasts and they are staunch proponents of 3K OCI. Here is a copy and paste from their website:
The most common cause of failure with valve cover gaskets is a lack of maintenance. With extended oil changes, we may deplete engine oil additives that help keep valve cover gaskets pliable.
Without this protection, gaskets and seals get hard and may start to leak.
What is your opinion of this statement? Are we being duped by our owner's manual instructions and our focus on oil analysis?
Here is how my original post should have read. Nothing else should have been included:
I started listening to AGCO Podcasts and they are staunch proponents of 3K OCI. Here is a copy and paste from their website:
The most common cause of failure with valve cover gaskets is a lack of maintenance. With extended oil changes, we may deplete engine oil additives that help keep valve cover gaskets pliable.
Without this protection, gaskets and seals get hard and may start to leak.
What is your opinion of this statement? Are we being duped by our owner's manual instructions and our focus on oil analysis?
What got me to thinking things can affect the seals and gaskets is the apparent success AT-205 has in certain situations.
I started my experiment last night by dumping a bottle in my warm crankcase and driving 1 1/2 hours.
I'll take it on another family Thanksgiving trip today to try and get a bunch of hours on it. We will know within
a week or so by looking at my driveway if the leaks have stopped.
My other question is what constitutes a "modern" car? 1980+ 1990+ 2000+ 2010+
Why do a lot of true mechanics by trade follow shorter OCI's than what is recommended in most owners' manuals? I know 4 and none of them go over 5K with synthetic oil.
See, back in the 1990's, I was an Amsoil devotee and was running 10K OCI's. Fast forward to 2000's (and this forum) I started learning things. Going forward to 2010's I started
changing things. Today, it's like some things I always thought were true may not be true at all.
I am so thankful for this forum. It is a wonderful help to me.
I started my experiment last night by dumping a bottle in my warm crankcase and driving 1 1/2 hours.
I'll take it on another family Thanksgiving trip today to try and get a bunch of hours on it. We will know within
a week or so by looking at my driveway if the leaks have stopped.
My other question is what constitutes a "modern" car? 1980+ 1990+ 2000+ 2010+
Why do a lot of true mechanics by trade follow shorter OCI's than what is recommended in most owners' manuals? I know 4 and none of them go over 5K with synthetic oil.
See, back in the 1990's, I was an Amsoil devotee and was running 10K OCI's. Fast forward to 2000's (and this forum) I started learning things. Going forward to 2010's I started
changing things. Today, it's like some things I always thought were true may not be true at all.
I am so thankful for this forum. It is a wonderful help to me.
Originally Posted by Gebo
What got me to thinking things can affect the seals and gaskets is the apparent success AT-205 has in certain situations.
I started my experiment last night by dumping a bottle in my warm crankcase and driving 1 1/2 hours.
I'll take it on another family Thanksgiving trip today to try and get a bunch of hours on it. We will know within
a week or so by looking at my driveway if the leaks have stopped.
My other question is what constitutes a "modern" car? 1980+ 1990+ 2000+ 2010+
Why do a lot of true mechanics by trade follow shorter OCI's than what is recommended in most owners' manuals? I know 4 and none of them go over 5K with synthetic oil.
See, back in the 1990's, I was an Amsoil devotee and was running 10K OCI's. Fast forward to 2000's (and this forum) I started learning things. Going forward to 2010's I started
changing things. Today, it's like some things I always thought were true may not be true at all.
I am so thankful for this forum. It is a wonderful help to me.
I have used Amsoil on and off for years. My current SUV with an Ecotec GDI engine, I will not go over 3k due to fuel dilution. Viscosity shears from 30W to 20W, Boron depletes by 80%, TBN drops significantly within 2k miles. Once it hits 5% dilution I change it.
GDI is one reason auto technicians follow shorter OCIs, especially Chevy and GMC techs.
What got me to thinking things can affect the seals and gaskets is the apparent success AT-205 has in certain situations.
I started my experiment last night by dumping a bottle in my warm crankcase and driving 1 1/2 hours.
I'll take it on another family Thanksgiving trip today to try and get a bunch of hours on it. We will know within
a week or so by looking at my driveway if the leaks have stopped.
My other question is what constitutes a "modern" car? 1980+ 1990+ 2000+ 2010+
Why do a lot of true mechanics by trade follow shorter OCI's than what is recommended in most owners' manuals? I know 4 and none of them go over 5K with synthetic oil.
See, back in the 1990's, I was an Amsoil devotee and was running 10K OCI's. Fast forward to 2000's (and this forum) I started learning things. Going forward to 2010's I started
changing things. Today, it's like some things I always thought were true may not be true at all.
I am so thankful for this forum. It is a wonderful help to me.
I have used Amsoil on and off for years. My current SUV with an Ecotec GDI engine, I will not go over 3k due to fuel dilution. Viscosity shears from 30W to 20W, Boron depletes by 80%, TBN drops significantly within 2k miles. Once it hits 5% dilution I change it.
GDI is one reason auto technicians follow shorter OCIs, especially Chevy and GMC techs.
Originally Posted by Gebo
Cam seal replacement labor on my car is very expensive as well. They gotta remove the cams.
I missed that these are VVTi UZ engines.....The O-ring in the VVT Phasers are a known leak point & are easily misdiagnosed as Cam Seals!
Cam seal replacement labor on my car is very expensive as well. They gotta remove the cams.
I missed that these are VVTi UZ engines.....The O-ring in the VVT Phasers are a known leak point & are easily misdiagnosed as Cam Seals!
Originally Posted by Gebo
What got me to thinking things can affect the seals and gaskets is the apparent success AT-205 has in certain situations.
The AT-205 SDS shows it to be 100% glycol ethers (solvents). Any chemists here to explain what it might do to rubber seals?
What got me to thinking things can affect the seals and gaskets is the apparent success AT-205 has in certain situations.
The AT-205 SDS shows it to be 100% glycol ethers (solvents). Any chemists here to explain what it might do to rubber seals?
Originally Posted by clinebarger
Originally Posted by Gebo
Cam seal replacement labor on my car is very expensive as well. They gotta remove the cams.
I missed that these are VVTi UZ engines.....The O-ring in the VVT Phasers are a known leak point & are easily misdiagnosed as Cam Seals!
Thank you for that info! How can I know this? Or can I? I am relying on a mechanic's diagnosis.
Gosh, I hope I ain't being lied to by my mechanic.
He's been really good but he found oil in the spark plug holes in my sons 09 Highlander and said he'd have to remove the heads to fix the leak. He said those tubes have come loose from the head. I asked him why he couldn't just replace those spark plug grommets. He said that would only be a 30% chance in fixing that oil seeping in the spark plug holes. I felt funny with that answer and now I'm feeling funny with the leaking cam seal diagnosis.
I'm losing confidence. Clinebarger, If you can help me, I would forever grateful. I'm hoping I ain't being deceived but if I am I need to know it now. My mechanic is a Lexus Master Tech and came highly recommended.
Originally Posted by Gebo
Cam seal replacement labor on my car is very expensive as well. They gotta remove the cams.
I missed that these are VVTi UZ engines.....The O-ring in the VVT Phasers are a known leak point & are easily misdiagnosed as Cam Seals!
Thank you for that info! How can I know this? Or can I? I am relying on a mechanic's diagnosis.
Gosh, I hope I ain't being lied to by my mechanic.
He's been really good but he found oil in the spark plug holes in my sons 09 Highlander and said he'd have to remove the heads to fix the leak. He said those tubes have come loose from the head. I asked him why he couldn't just replace those spark plug grommets. He said that would only be a 30% chance in fixing that oil seeping in the spark plug holes. I felt funny with that answer and now I'm feeling funny with the leaking cam seal diagnosis.
I'm losing confidence. Clinebarger, If you can help me, I would forever grateful. I'm hoping I ain't being deceived but if I am I need to know it now. My mechanic is a Lexus Master Tech and came highly recommended.
Originally Posted by doitmyself
Originally Posted by Gebo
What got me to thinking things can affect the seals and gaskets is the apparent success AT-205 has in certain situations.
The AT-205 SDS shows it to be 100% glycol ethers (solvents). Any chemists here to explain what it might do to rubber seals?
I got to do more driving hours before I check for spots in the driveway. It's been raining so much I couldn't check it now anyways. I got 2 long drive hospital visits next week so I'll have 10 hours running the AT-205 by next Wednesday.
Originally Posted by Gebo
What got me to thinking things can affect the seals and gaskets is the apparent success AT-205 has in certain situations.
The AT-205 SDS shows it to be 100% glycol ethers (solvents). Any chemists here to explain what it might do to rubber seals?
I got to do more driving hours before I check for spots in the driveway. It's been raining so much I couldn't check it now anyways. I got 2 long drive hospital visits next week so I'll have 10 hours running the AT-205 by next Wednesday.
Originally Posted by Ihatetochangeoil
The NEWEST car I have is 15 years old. It runs, stops, steers and sounds like a new car, and leaks nothing. THAT being said, it is BITOG maintained; I've got slightly more than 1/2 your miles...150K+, I've replaced valve cover gaskets, oil pan gasket, transmission oil cooler lines, PS fluid lines, heater hoses & heater core, serpentine belt, water pump, A/C compressor & evaporator core, etc., anything that leaks or breaks...
I agree with simple_gifts, it is simply Old car issues. My opinion is that no amount of oil change frequency is going to preserve old valve cover gaskets. On my "old car" I love that everything works and the icing is it's paid for.....and yes, it has a few dents and dings and I could care less who parks next to me....I love it. BTW, I use Amsoil for all fluids, even grease and PS fluid, and I change oil ~10-12K, after all, I'm using the best oil on the market.
Simple facts: older cars REQUIRE more maintenance.
Now this^^^is a post I like because it is truthful. I can't stand the...I have 300,000 miles on my car and all I've done is oil changes, garbage. It's not real. Give me the real story, the whole story, every time.
I took a Honda Accord to 289,000 miles. It takes a whole lot to get a car that far. Everything eventually leaks. And when it does? You can either fix it or don't. It's that simple.
Right now we have a 2008 Honda CRV in the family, it has 139,000 miles...the tranmssion leaks, and the rear differential leaks. I won't fix either because it leaks where the units split in two, it's not a simple repair like a valve cover or pan gasket. So I'll just make sure the Fluid is full and drive. But if I could fix it I would.
The NEWEST car I have is 15 years old. It runs, stops, steers and sounds like a new car, and leaks nothing. THAT being said, it is BITOG maintained; I've got slightly more than 1/2 your miles...150K+, I've replaced valve cover gaskets, oil pan gasket, transmission oil cooler lines, PS fluid lines, heater hoses & heater core, serpentine belt, water pump, A/C compressor & evaporator core, etc., anything that leaks or breaks...
I agree with simple_gifts, it is simply Old car issues. My opinion is that no amount of oil change frequency is going to preserve old valve cover gaskets. On my "old car" I love that everything works and the icing is it's paid for.....and yes, it has a few dents and dings and I could care less who parks next to me....I love it. BTW, I use Amsoil for all fluids, even grease and PS fluid, and I change oil ~10-12K, after all, I'm using the best oil on the market.
Now this^^^is a post I like because it is truthful. I can't stand the...I have 300,000 miles on my car and all I've done is oil changes, garbage. It's not real. Give me the real story, the whole story, every time.
I took a Honda Accord to 289,000 miles. It takes a whole lot to get a car that far. Everything eventually leaks. And when it does? You can either fix it or don't. It's that simple.
Right now we have a 2008 Honda CRV in the family, it has 139,000 miles...the tranmssion leaks, and the rear differential leaks. I won't fix either because it leaks where the units split in two, it's not a simple repair like a valve cover or pan gasket. So I'll just make sure the Fluid is full and drive. But if I could fix it I would.
Last edited:
- Status
Similar threads
