I posted this in the additives forum but I figured it was relevant here as well.
I drive a Subaru and Subarus are notorious for leaky seals. Right now my 15 year old Subaru (85,000 miles) is nice and dry. I recently changed the valve cover gaskets and the previous owner did the cam seals. I would like to keep it dry. As such, I have been running high mileage oils with seal conditioners and, specificaly, the Quaker State HM oil. It was rated pretty highly on the motoroilevaluator.com site. But I would like something better for my car and I wanted longer OCIs. So I have switched to Mobil 1 High Mileage. Of all the synthetic high mileage oils, it rated out the best, although the Valvoline full synthetic was pretty high too.
But now I am hearing that Mobil 1 may not be good for Subarus. The main complaint is that it leaches out metals and particularly copper. On the additives forum they said that the copper would come from the bearings. Perhaps the cases where copper was high were when M1 was used in a newer engine. I have also read that new engines tend to leach out metals until they are fully broken in.
Also, people have complained that 5W30 M1 has a tendency to shear at high RPMs. I don't normally rev my engines so I not too concerned.
The reports on M1 being bad for Subarus came from the Nasioc website. Several people who have had their engine bearings go on them were using M1 at the time and blamed it on the oil. I honestly can't tell you how many of them were running turbos or how many of them regularly revved the [censored] out of their engines on a regular basis. I'm sure the oil saw stress in these cases and I'm sure the bearings did as well. However, you don't ever want to just turn a blind eye to such reports.
What I am guessing is that these guys really pushed their engines in more ways than just one. I'm also guessing that they were running them in hot weather and/or using 5W30 standard M1. It is possible that they did experience shear in their oil due to the use conditions and the same use conditions were stressing the bearings. If all of my assumtions are true, they probably would have been fine with 5W40 or 10W40 M1 but they pushed the limits on the 5W30.
Going to a 5W40 and, specifically, Redline 5W40 would seem to be good from both standpoints of shear and damage to metal parts. But then I would lose my seal conditioners. The 40W would help with shear and our summer temps can get over 100F for a few days but, when we do, I don't stress my car. We see temps below 0F far more often. That is one reason I want synthetic and a 5W one at that. I have also read that older engines (mileage, not age) like heavier oils since the bearing passages open up. I'm not sure if my 85K mile engine is there yet though. Also, this engine is known for tight passages by design. So frequent low temperatures and tight passages (assuming they are still tight) are both good reasons for running 5W. The main reasons for wanting 5W40 versus 5W30 would be the aforementioned shear, the handful of 100F days we get and the possibility that my engine passages have opened up.
The M1 5W30 HM I am now using is a bit of a comprimise since the additive pack raises the HTHS and the warm viscosity. Perhaps that is good enough to accomodate the reasons I gave above for wanting to move to a 5W40.
But here is my question, can I add something to the Redline oil to make it into a high mileage oil? I am thinking of the following:
1. Lubegard Bio-Tech Engine Oil Protectant
2. ATP AT-205 Re-seal
3. Lubro-Moly Motor Oil Saver
4. Justice Brothers Engine Stop-Leak
I am thinking of adding one of these in less than full strength amounts to just get some conditioning versus a leak fix which I don't really need at this time. I also looked at Auto-Rx but they specifically said it shouldn't be added to ester based oils (group V) due to competition for coating the metal surfaces.
Thoughts? Ideas? Suggestions?
Even if M1 5W30 HM is good enough for my purposes, I am still academically curious as to whether or not Redline 5W40 could be modified into a psuedo-HM oil by adding the products I mentioned above. The Lubegard and Lubro-moly products seem to have a good reputation and the ATP product specifically states that it conditions seals and does not swell them like solvents will.
I drive a Subaru and Subarus are notorious for leaky seals. Right now my 15 year old Subaru (85,000 miles) is nice and dry. I recently changed the valve cover gaskets and the previous owner did the cam seals. I would like to keep it dry. As such, I have been running high mileage oils with seal conditioners and, specificaly, the Quaker State HM oil. It was rated pretty highly on the motoroilevaluator.com site. But I would like something better for my car and I wanted longer OCIs. So I have switched to Mobil 1 High Mileage. Of all the synthetic high mileage oils, it rated out the best, although the Valvoline full synthetic was pretty high too.
But now I am hearing that Mobil 1 may not be good for Subarus. The main complaint is that it leaches out metals and particularly copper. On the additives forum they said that the copper would come from the bearings. Perhaps the cases where copper was high were when M1 was used in a newer engine. I have also read that new engines tend to leach out metals until they are fully broken in.
Also, people have complained that 5W30 M1 has a tendency to shear at high RPMs. I don't normally rev my engines so I not too concerned.
The reports on M1 being bad for Subarus came from the Nasioc website. Several people who have had their engine bearings go on them were using M1 at the time and blamed it on the oil. I honestly can't tell you how many of them were running turbos or how many of them regularly revved the [censored] out of their engines on a regular basis. I'm sure the oil saw stress in these cases and I'm sure the bearings did as well. However, you don't ever want to just turn a blind eye to such reports.
What I am guessing is that these guys really pushed their engines in more ways than just one. I'm also guessing that they were running them in hot weather and/or using 5W30 standard M1. It is possible that they did experience shear in their oil due to the use conditions and the same use conditions were stressing the bearings. If all of my assumtions are true, they probably would have been fine with 5W40 or 10W40 M1 but they pushed the limits on the 5W30.
Going to a 5W40 and, specifically, Redline 5W40 would seem to be good from both standpoints of shear and damage to metal parts. But then I would lose my seal conditioners. The 40W would help with shear and our summer temps can get over 100F for a few days but, when we do, I don't stress my car. We see temps below 0F far more often. That is one reason I want synthetic and a 5W one at that. I have also read that older engines (mileage, not age) like heavier oils since the bearing passages open up. I'm not sure if my 85K mile engine is there yet though. Also, this engine is known for tight passages by design. So frequent low temperatures and tight passages (assuming they are still tight) are both good reasons for running 5W. The main reasons for wanting 5W40 versus 5W30 would be the aforementioned shear, the handful of 100F days we get and the possibility that my engine passages have opened up.
The M1 5W30 HM I am now using is a bit of a comprimise since the additive pack raises the HTHS and the warm viscosity. Perhaps that is good enough to accomodate the reasons I gave above for wanting to move to a 5W40.
But here is my question, can I add something to the Redline oil to make it into a high mileage oil? I am thinking of the following:
1. Lubegard Bio-Tech Engine Oil Protectant
2. ATP AT-205 Re-seal
3. Lubro-Moly Motor Oil Saver
4. Justice Brothers Engine Stop-Leak
I am thinking of adding one of these in less than full strength amounts to just get some conditioning versus a leak fix which I don't really need at this time. I also looked at Auto-Rx but they specifically said it shouldn't be added to ester based oils (group V) due to competition for coating the metal surfaces.
Thoughts? Ideas? Suggestions?
Even if M1 5W30 HM is good enough for my purposes, I am still academically curious as to whether or not Redline 5W40 could be modified into a psuedo-HM oil by adding the products I mentioned above. The Lubegard and Lubro-moly products seem to have a good reputation and the ATP product specifically states that it conditions seals and does not swell them like solvents will.
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