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New motor oil wear problems on older engines
- Thread starter Ecomike
- Start date
- Location
- NJ, U.S.A.
I do - Nothing in my little fleet is less than 5 years old - my TDI is five an a half now, though that's not old enough to be affected by this. However, two of them are old enough that this whole ZDDP thing is preying on my mind.scorpio_vette said:
Those two are my '92 XJ (~222K, owned since December 1997) and my '84 Omni (~140K, owned since about Easter of 1992) - neither of which are DDs any more, mind you, but I'm not exactly comfortable with the idea of switching either over to synthetics, given their ages.
I will continue to read this thread with interest, to see how things develop.
Synthetic in the SM grade will have the same zinc and phos levels as conventional. Again, none of you really stretch out the oil long enough to deplete the additive packs. Most of you are 5k and under oil changers ...or so I imagine. 5k is an extended drain to some people who are trapped in the 3k/3m prison.
mikegronholz
NAXJA Forum User
- Location
- Fort Worth
No sooner did i post that she isn't "crying" than i crawl underneath and find a "film" :doh: ... so this weekend .. out with the syn, and in with the dino. i think I am going to do dino Rotella and a bottle of Lucas.
mikegronholz
NAXJA Forum User
- Location
- Fort Worth
RyanM said:Lucas and its 5ppm of zinc
Not using it for zinc ... hoping it will help gets the seals sealing again 100%. The o'Reilly's by me still has cases of STP Blue ... I'd go that route if i feel the need for a zinc additive. I am going to run 3000 on Rotella dino and do a blackstone ... that will show where that oil stands.
JNickel101
NAXJA Forum User
- Location
- Alamogordo, NM
Anyone care to summerize this "short" thread?
I'm in the USAF, and at our Auto Shop, they have a pretty big selection of oils....was looking and most were SM and SL.....the RP 10w40 was only SL....but their 10w30 was SM/SL....Castrol GTX was also SM/SL.....
I'm in the USAF, and at our Auto Shop, they have a pretty big selection of oils....was looking and most were SM and SL.....the RP 10w40 was only SL....but their 10w30 was SM/SL....Castrol GTX was also SM/SL.....
bewilderedbeast
NAXJA Forum User
- Location
- Seattle
mikegronholz said:
You might want to give Auto-RX, sometimes it will slow down or stop weeping or leaking seals. My rear main has been weeping a little, not a lot, just enough to wet the bottom of the oil pan. Auto-RX has almost made that stop. Almost, but not quite.
mikegronholz
NAXJA Forum User
- Location
- Fort Worth
Sure ... there are 2 major frames of thought ...JNickel101 said:Anyone care to summerize this "short" thread?
I'm in the USAF, and at our Auto Shop, they have a pretty big selection of oils....was looking and most were SM and SL.....the RP 10w40 was only SL....but their 10w30 was SM/SL....Castrol GTX was also SM/SL.....
1) We're all freakin screwed ... your motor will die tomorrow if you run SM oil
2) SL, SM ... whatere ... it's oil
Those are the extremes ... it's seems to be all about the zinc. I just got off the phone with yet another oil company ... Shell this time. The chemist (not a customer service guy apparently ... man was he spuing alot of words i had never heard) basically said this "I would love to see definitive prrof that 1000ppm and 1200ppm caused different amounts of wear. He echoed exactly what was said abouve ... it is all rpm\sping rate based. He sadi in a stock built engine, he would expect 1000ppm and 1200ppm to wear the exact same ... assuming we consumers follow the propaganda that his own company has convinced us to do ... change oil often. He said if you change at 3000mi, most quality oils on the market have not even begun to breakdown.
So ... there you go. The way i'm starting to look at it is this (much like the head cracking issues) ... we are the internet savvy users of the XJ ... BUT we are a VERY SMALL subset of total users out there. If we show a 10% failure of x, when we are about 2% of total users, then effectively we show a representative rate of failure of .2%. Just like a political poll ... if you "randomly select" 100 liberal leaning people and ask them Bush's approval rating, your numbers are skewed. We are the small population with an extreme focus. There will be literally thousands upon thousands of XJ, TJ, ZJ owners out there that will pull in to a *gulp* Jiffy Lube and say "fill 'er up" and will never know to ask anything buy the price. They may last 300000 miles, maybe not. Only time will tell. So, I'm putting dino back in mine in hopes of easing the seaping on the synthetic. I'm using rotella cause it's inexpensive and easy to come by.
- Location
- MilkyWay Galaxy
Some of you (an I am not naming names) need to back to my original post, post #1 and follow the link
http://www.lnengineering.com/oil.html
and look at the large number of oil analysis test results posted and the ZN & P average concentrations for each of the four specs we have been discussing, as well as the concentrations in various brands. Please note that the results list the date of the sample and the Spec (SL/SM or CI-/CJ-4). Also note that although ZDDP is consumed, the elemental Zn and P is not, so the oil test results for Zn & P concentrations in used oil are going to be very close test results for the original new oil.
Havoline 20W50 API SM Dyno oil was less than 500 ppm of Zn and P.
From the middle of that linked page at:
http://www.lnengineering.com/oil.html
I quote:
"How did you determine the recommended 0.12% Zn and P level (ZDP, a.k.a. ZDDP)?
There are many excellent SAE technical papers on the subject, but the one I found most interested was from 1977 titled "Cam and Lifter Wear as Affected by Engine Oil ZDP Concentration and Type." There is some background that is needed to shed light on their results. First of all, there are different types of ZDPs. There is an Aryl ZDP which is the most stable form. There is also an Alkyl ZDP which although is not as stable, exhibits the best wear protection.
In various fleet tests, it was determined that the best performance was from oils containting all Alkyl ZDPs or predominantly Alkyl ZDP blends. They also looked at the performance of "ashless" oils (0.03-0.05% Sulpherated Ash) vs oils with normal levels (0.11% or higher) and it would appear that oils with lower ash levels needed more ZDP to provide the same level of protection.
I bring this up since the newest CJ-4 and SM oils require significantly lower ash levels, less than 0.10%. Across the Indianapolis, Pheonix, and Los Angeles taxi fleets observed, oils with 0.11-0.13% Alkyl ZDP resulted in the lowest combined and average cam wear measured. Levels of wear remained low with oils with Alkyl ZDPs as high as 0.19%.
The oils that had at least 0.07% Alkyl combined with 0.05% Aryl performed just as well as oils with higher Alkyl only ZDP levels, suggesting some sort of synergistic properties of the decomposition products of the Alkyl/Aryl blend. Comined ZDP levels of the Aryl and Alkyl blend were min. 0.12%. Our assumption with choosing a minimum Zn and P levels of 0.12% is on the assumption that the best combo of ZDPs are being used for wear performance, not longer drain intervals.
More recently, in the development of the IIIG sequence, developers went so far as to say that there was no need for the VD and VE sequences for testing of OHV (overhead valve) engines because these engines are not commercially available as new anymore and do not refect the needs of more modern engines.
In a SAE paper titled "How Much ZDP is Enough?" from 2004, the resulting trend of decreasing phosphorus is as a direct result of observations that modern engines, with lower spring pressures and lighter vavletrain, including multiple intake and exhaust valves, seems to require only .03% Ph to prevent wear. It was further documented that by increasing to 180 lbs of spring pressure with a .03% ZDP resulted in 267 mil of wear where with .05% ZDP concentration tests resulted in 26 mil of wear. That same .05% oil with just 205 lbs of pressure resulted in 153 mil of wear, requiring .095% ZDP to reduce wear, resulting in just 16 mil. The ZDP requirements of a motor oil are directly proportional to
valvetrain spring pressure.
Most older SOHC and pushrod aircooled Porsche engines have significantly more pressure, as a stock street pushrod Porsche 356 or 912 engine exceeds these levels of spring pressure compared to the levels of pressure on modern engines, for which oils are tested for.
Newer oils will continue this trend, leaving older engines with fewer and fewer choices for motor oils compliant with the requirements of these older valvetrains, hence our recommendations for using oils with higher levels of ZDPs as substantiated by earlier testing sequences and the results on engines similar to our older aircooled Porsches."
Ok, so what is the OEM 4.0, Renix and HO valve spring pressure?
) need to back to my original post, post #1 and follow the link http://www.lnengineering.com/oil.html
and look at the large number of oil analysis test results posted and the ZN & P average concentrations for each of the four specs we have been discussing, as well as the concentrations in various brands. Please note that the results list the date of the sample and the Spec (SL/SM or CI-/CJ-4). Also note that although ZDDP is consumed, the elemental Zn and P is not, so the oil test results for Zn & P concentrations in used oil are going to be very close test results for the original new oil.
Havoline 20W50 API SM Dyno oil was less than 500 ppm of Zn and P.
From the middle of that linked page at:
http://www.lnengineering.com/oil.html
I quote:
"How did you determine the recommended 0.12% Zn and P level (ZDP, a.k.a. ZDDP)?
There are many excellent SAE technical papers on the subject, but the one I found most interested was from 1977 titled "Cam and Lifter Wear as Affected by Engine Oil ZDP Concentration and Type." There is some background that is needed to shed light on their results. First of all, there are different types of ZDPs. There is an Aryl ZDP which is the most stable form. There is also an Alkyl ZDP which although is not as stable, exhibits the best wear protection.
In various fleet tests, it was determined that the best performance was from oils containting all Alkyl ZDPs or predominantly Alkyl ZDP blends. They also looked at the performance of "ashless" oils (0.03-0.05% Sulpherated Ash) vs oils with normal levels (0.11% or higher) and it would appear that oils with lower ash levels needed more ZDP to provide the same level of protection.
I bring this up since the newest CJ-4 and SM oils require significantly lower ash levels, less than 0.10%. Across the Indianapolis, Pheonix, and Los Angeles taxi fleets observed, oils with 0.11-0.13% Alkyl ZDP resulted in the lowest combined and average cam wear measured. Levels of wear remained low with oils with Alkyl ZDPs as high as 0.19%.
The oils that had at least 0.07% Alkyl combined with 0.05% Aryl performed just as well as oils with higher Alkyl only ZDP levels, suggesting some sort of synergistic properties of the decomposition products of the Alkyl/Aryl blend. Comined ZDP levels of the Aryl and Alkyl blend were min. 0.12%. Our assumption with choosing a minimum Zn and P levels of 0.12% is on the assumption that the best combo of ZDPs are being used for wear performance, not longer drain intervals.
More recently, in the development of the IIIG sequence, developers went so far as to say that there was no need for the VD and VE sequences for testing of OHV (overhead valve) engines because these engines are not commercially available as new anymore and do not refect the needs of more modern engines.
In a SAE paper titled "How Much ZDP is Enough?" from 2004, the resulting trend of decreasing phosphorus is as a direct result of observations that modern engines, with lower spring pressures and lighter vavletrain, including multiple intake and exhaust valves, seems to require only .03% Ph to prevent wear. It was further documented that by increasing to 180 lbs of spring pressure with a .03% ZDP resulted in 267 mil of wear where with .05% ZDP concentration tests resulted in 26 mil of wear. That same .05% oil with just 205 lbs of pressure resulted in 153 mil of wear, requiring .095% ZDP to reduce wear, resulting in just 16 mil. The ZDP requirements of a motor oil are directly proportional to
valvetrain spring pressure.
Most older SOHC and pushrod aircooled Porsche engines have significantly more pressure, as a stock street pushrod Porsche 356 or 912 engine exceeds these levels of spring pressure compared to the levels of pressure on modern engines, for which oils are tested for.
Newer oils will continue this trend, leaving older engines with fewer and fewer choices for motor oils compliant with the requirements of these older valvetrains, hence our recommendations for using oils with higher levels of ZDPs as substantiated by earlier testing sequences and the results on engines similar to our older aircooled Porsches."
Ok, so what is the OEM 4.0, Renix and HO valve spring pressure?
200lbf (force) there is no spec for the seat pressure ..but I imagine it's quite low. That's from the 1999 FSM. It's, naturally, the same for the 2.5
I think that you anoint our beloved 4.0 with too many magical potent powers that it does not have in terms of valve train load.
I think that you anoint our beloved 4.0 with too many magical potent powers that it does not have in terms of valve train load.
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..and they asked G'Kar, "What is truth ..and what is God?"
G'kar explains:
“ If I take a lamp and shine toward the wall, a bright spot will appear on the wall. The lamp is our search for truth, for understanding. Too often we assume the light on the wall is God, but the light is not the goal of the search, it is the result of the search. The more intense the search, the brighter the light on the wall. The brighter the light on the wall, the greater the revelation upon seeing it. Similarly, someone who does not search, who does not bring a lantern with him, sees nothing. What we perceive as God is the by-product of our search for God. It may simply be an appreciation of the light, pure and unblemished. Not understanding that it comes from us, sometimes, we stand in front of the light and assume we are the center of the universe. God looks astonishingly like we do. Or we turn to look at our shadow and assume all is darkness. If we allow ourselves to get in the way, we defeat the purpose - which is use the light of our search to illuminate the wall in all its beauty and all it flaws, and in so doing, better understand the world around us. ”
Again, G'Kar is asked, "Yes, but what is truth and what is GOD?"
G'Kar, realizing the futility says, "Truth is the river ..and God is the mouth of the river."
Be afraid. Be very afraid. - Genna Davis in The Fly
G'kar explains:
“ If I take a lamp and shine toward the wall, a bright spot will appear on the wall. The lamp is our search for truth, for understanding. Too often we assume the light on the wall is God, but the light is not the goal of the search, it is the result of the search. The more intense the search, the brighter the light on the wall. The brighter the light on the wall, the greater the revelation upon seeing it. Similarly, someone who does not search, who does not bring a lantern with him, sees nothing. What we perceive as God is the by-product of our search for God. It may simply be an appreciation of the light, pure and unblemished. Not understanding that it comes from us, sometimes, we stand in front of the light and assume we are the center of the universe. God looks astonishingly like we do. Or we turn to look at our shadow and assume all is darkness. If we allow ourselves to get in the way, we defeat the purpose - which is use the light of our search to illuminate the wall in all its beauty and all it flaws, and in so doing, better understand the world around us. ”
Again, G'Kar is asked, "Yes, but what is truth and what is GOD?"
G'Kar, realizing the futility says, "Truth is the river ..and God is the mouth of the river."
Be afraid. Be very afraid. - Genna Davis in The Fly
- Location
- MilkyWay Galaxy
OK since you have problem with the word "thickness" let's call it surface density to be more precise. Surface density being defined as the number of molecules, or moles per unit surface area. The higher the ZDDP concentration (up to about .19% as the upper limit point from what I recall reading) the higher the surface density of ZDDP molecules in potentially high wear areas, and thus the less wear in those areas.geeaea said:
I already posted reasons earlier why the ZDDP consumption rate is not truely linear in the real world (versus lab engine trials under controlled conditions) and why it is not affected only by cumulative engine revolutions (RPM times elapsed time)
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Mike ...there is a decay rate. The incremental or decremental aspect of it can only manifest itself in length of service. Think about it.
If you admit that zddp is sacrificial ...(enough evidence for anyone to accept) ..then there is a point where there is less of it (in its usable form = there's no "uptake" of the fundamental zinc and phos = they do, however, volatilize). That sensibly leads most to reason that a 1200 ppm starting point ....or a 900 ppm starting point are GOING to resemble each other in effective worth AT SOME POINT in the OCI.
We then would sensibly reason that it's down to a matter of length of OCI that will determine your TRUE level of viable zddp in the oil. Naturally, if you start with more ...you'll end with more ...but you'll be dealing with "less" of it from the first time you bump the key ..and every revolution after that until you drain it out.
Go ahead and put both levels (900/1200) on any decay curve that you want. Use exponential if you want. Now plot that over a given mileage (make it up) ..there IS - by any reasonable analysis, going to be somewhere on the graph where the lines occupy the exact same coordinates on one plane. They will occupy it at different "times" (mileages) ..but THEY WILL BE AT THE SAME LEVELS IN CONCENTRATION.
I'm saying that you're (typically) draining your oil before EITHER of those levels are damaging to your engine. If you're a 3k/3m prisoner ...you've (most likely) got more active zddp than someone running SL out to a sensible OCI.
If you can throw a bucket of water on that notion ..I'll end my contributions to this minor matter (imo). I have enjoyed, and do admire, your apparent ability to find only that which tends to support this notion and your complete rejection of offered, anxiety easing, information. A tip of the hat to you, sir
Cheers
If you admit that zddp is sacrificial ...(enough evidence for anyone to accept) ..then there is a point where there is less of it (in its usable form = there's no "uptake" of the fundamental zinc and phos = they do, however, volatilize). That sensibly leads most to reason that a 1200 ppm starting point ....or a 900 ppm starting point are GOING to resemble each other in effective worth AT SOME POINT in the OCI.
We then would sensibly reason that it's down to a matter of length of OCI that will determine your TRUE level of viable zddp in the oil. Naturally, if you start with more ...you'll end with more ...but you'll be dealing with "less" of it from the first time you bump the key ..and every revolution after that until you drain it out.
Go ahead and put both levels (900/1200) on any decay curve that you want. Use exponential if you want. Now plot that over a given mileage (make it up) ..there IS - by any reasonable analysis, going to be somewhere on the graph where the lines occupy the exact same coordinates on one plane. They will occupy it at different "times" (mileages) ..but THEY WILL BE AT THE SAME LEVELS IN CONCENTRATION.
I'm saying that you're (typically) draining your oil before EITHER of those levels are damaging to your engine. If you're a 3k/3m prisoner ...you've (most likely) got more active zddp than someone running SL out to a sensible OCI.
If you can throw a bucket of water on that notion ..I'll end my contributions to this minor matter (imo). I have enjoyed, and do admire, your apparent ability to find only that which tends to support this notion and your complete rejection of offered, anxiety easing, information. A tip of the hat to you, sir
Cheers
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corbinafly
"Mmmm. More please."
- Location
- lakewood,ca
In your analysis you assume that only a certain amount of zddp can be in "decay mode" at any given time. But is that the case? Maybe the higher levels of zddp would equate to higher ppm of it being decayed at any given time. Meaning more of it is in use. I'm just thinking out loud here, but until someone can show that, regardless of the % of zddp in the system, only a finite amount of it can be in "use" at any given time/point, your argument might not be valid.geeaea said:Mike ...there is a decay rate. The incremental or decremental aspect of it can only manifest itself in length of service. Think about it.
If you admit that zddp is sacrificial ...(enough evidence for anyone to accept) ..then there is a point where there is less of it (in its usable form = there's no "uptake" of the fundamental zinc and phos = they do, however, volatilize). That sensibly leads most to reason that a 1200 ppm starting point ....or a 900 ppm starting point are GOING to resemble each other in effective worth AT SOME POINT in the OCI.
We then would sensibly reason that it's down to a matter of length of OCI that will determine your TRUE level of viable zddp in the oil. Naturally, if you start with more ...you'll end with more ...but you'll be dealing with "less" of it from the first time you bump the key ..and every revolution after that until you drain it out.
Go ahead and put both levels (900/1200) on any decay curve that you want. Use exponential if you want. Now plot that over a given mileage (make it up) ..there IS - by any reasonable analysis, going to be somewhere on the graph where the lines occupy the exact same coordinates on one plane. They will occupy it at different "times" (mileages) ..but THEY WILL BE AT THE SAME LEVELS IN CONCENTRATION.
I'm saying that you're (typically) draining your oil before EITHER of those levels are damaging to your engine. If you're a 3k/3m prisoner ...you've (most likely) got more active zddp than someone running SL out to a sensible OCI.
If you can throw a bucket of water on that notion ..I'll end my contributions to this minor matter (imo). I have enjoyed, and do admire, your apparent ability to find only that which tends to support this notion and your complete rejection of offered, anxiety easing, information. A tip of the hat to you, sir
Cheers
Thoughts??
Kyung
sjkimmel99
NAXJA Forum User
- Location
- Phoenix, Az
Here's an interesting article:
http://www.revsearch.com/dynamometer/rollervsflattappet.html
This guy claims that Schubeck flat tappet lifters are made of a material that resists or is impervious to wear. Also points to a Hughes Engines company as selling an "extreme pressure" oil additive.
Schubeck's web site, in the "solid lifter" section gives some marketing blather about their lifters. I called the number at the bottom of the page but it just rang.
http://www.schubeckracing.com/index.html
Hughes Engines here:
http://www.hughesengines.com/
show both the oil additive as well as a lifter with an oiling hole in the bottom. Hmm, it's a solid lifter so that'd be a pita to deal with.
The oil additive is $9.50 per pint (treats 5 quarts) but it only talks about moly as the additive. Get a bit over $1 off by the case.
http://www.revsearch.com/dynamometer/rollervsflattappet.html
This guy claims that Schubeck flat tappet lifters are made of a material that resists or is impervious to wear. Also points to a Hughes Engines company as selling an "extreme pressure" oil additive.
Schubeck's web site, in the "solid lifter" section gives some marketing blather about their lifters. I called the number at the bottom of the page but it just rang.
http://www.schubeckracing.com/index.html
Hughes Engines here:
http://www.hughesengines.com/
show both the oil additive as well as a lifter with an oiling hole in the bottom. Hmm, it's a solid lifter so that'd be a pita to deal with.
The oil additive is $9.50 per pint (treats 5 quarts) but it only talks about moly as the additive. Get a bit over $1 off by the case.
sjkimmel99
NAXJA Forum User
- Location
- Phoenix, Az
The Hughes Engines site has some "tech" articles that talk about the oil additives and explains why the moly in their additive works.
One of the articles contains a link to a Shell Canada FAQ about Rotella:
http://www.shell.ca/home/content/ca-en/shell_for_businesses/lubricants/rotella/cj4/cj4_faq.html#20
question #20 - will there be less zddp in Shell Rotella in 2007 - answer: yes. They then go on to say that CJ-4 rated oils provide improved performance over CI-4+ anyway.
question #19 - will you produce CI-4+ oils - answer: yes, under the Rimula brand if there is sufficient demand from customers.
One of the articles contains a link to a Shell Canada FAQ about Rotella:
http://www.shell.ca/home/content/ca-en/shell_for_businesses/lubricants/rotella/cj4/cj4_faq.html#20
question #20 - will there be less zddp in Shell Rotella in 2007 - answer: yes. They then go on to say that CJ-4 rated oils provide improved performance over CI-4+ anyway.
question #19 - will you produce CI-4+ oils - answer: yes, under the Rimula brand if there is sufficient demand from customers.
Let me share some notes from Red Line about zddp.
Lubricants Notes from Redline
By Roy Howell, Chief Chemist, Redline Synthetic Oil Company, Formerly of Lubrisol, 7 April 1992
Notes taken by Jack L. Poller.
The surface gets plated with either Iron Phosphate or Iron Sulfate, both of which are softer than the base Iron. This chemical reaction occurs in the 300 to 400 F range, and the Zinc is a temperature controlling carrier (controls the temperature at which the reaction occurs. When the two metal surfaces come in contact, a small amount of the surface plating is 'scraped' off of the surface. This is replenished by more ZDP contact with the metal. This action prevents the metals welding through heat generated by high friction contact. The ZDP in the lubricant may last up to 20,000 miles.
So, we have a FIFO type thing with a full magazine to "refill" the gap.
So, I reassert that a lower zddp starting level will mean that you will have less latitude in length of OCI.
This is somewhat, IIRC, supported in the current pushrod engines offered by DC. They spec SM oil over 5000 mile OCI's ..as opposed to most everyone else, with roller valve trains can go much further (although this is not a given just because they have roller valve trains).
Lubricants Notes from Redline
By Roy Howell, Chief Chemist, Redline Synthetic Oil Company, Formerly of Lubrisol, 7 April 1992
Notes taken by Jack L. Poller.
The surface gets plated with either Iron Phosphate or Iron Sulfate, both of which are softer than the base Iron. This chemical reaction occurs in the 300 to 400 F range, and the Zinc is a temperature controlling carrier (controls the temperature at which the reaction occurs. When the two metal surfaces come in contact, a small amount of the surface plating is 'scraped' off of the surface. This is replenished by more ZDP contact with the metal. This action prevents the metals welding through heat generated by high friction contact. The ZDP in the lubricant may last up to 20,000 miles.
So, we have a FIFO type thing with a full magazine to "refill" the gap.
So, I reassert that a lower zddp starting level will mean that you will have less latitude in length of OCI.
This is somewhat, IIRC, supported in the current pushrod engines offered by DC. They spec SM oil over 5000 mile OCI's ..as opposed to most everyone else, with roller valve trains can go much further (although this is not a given just because they have roller valve trains).
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heyhar
NAXJA Forum User
- Location
- PA (near Poconos)
I looked at the links, and noticed that Castrol's 'high mileage' oil had high levels of what the others are lowering. Would these be a safe bet? Also, would a 'high-mileage' or 'older vehicle' type of oil do a nice job of swelling the main seals? A few years ago, I ran a few oil changes of partial synthetic oil in hopes of increasing gas mileage in my '92. All I increased was the stain in my driveway. From not burning or leaking a drop to about a quart every oil change (3k miles). It's been sitting since an accident in Jan., but it should be ready to go in about a week, so I need to put a fresh shot of oil in. I've started using Castrol 10-40 in my '96, as it dosen't say 'gas saver' in the little circle, as do the lighter grades. Any suggestions would be appreciated. Thanks, Ray.
