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New oils, bad for old cars!!

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Very interesting, I have had problems with my car and after a lot of frustration traced it to the cam and lifters. I did not want to believe a car with 45K would have this problem. So, does anyone have the address where I can send the repair bill to Uncle Sam? /ubbthreads/images/graemlins/confused.gif
 
In the first two post of gjh link it says that diesel motor oil like delo and synthetic redline oil have enough zinc, but if you go to the bottom (3rd) John Deere link it gives a list of how much zinc is in the major brands. It says that Redline and Delo have no zinc.----What to believe???
 
I have seen one brand advertise that it is the right oil for high mileage cars; I think it is Quaker State. I wonder if it has more zinc than the non-high mileage oils?
 
Other good diesel oils are Mobil's Delvac and Pennzoil's Long-Life...I have used both in the past and, according to my oil samples from my engines, they hold their viscosity better than Shell Rotella...at least in OTR diesel service with extended drain intervals.
 
A quick search of the mobil 1 spec sheet shows zinc as part of their formulation https://neptune.spacebears.com/cars/stories/oil-life.html . I have been using their 15-50w in the summer & 10-30 in the winter with excelent results. Oil consumption is minimal, my magnetic drain plug is super clean & most of all , oil pressure is very stable from hot to cold and highway to idle. I have used Castrol in the past but have always found lower oil pressure readings & a noisier valve train . I'm sure it does it's job but a good sign of an oil doing it's job would be good viscosity recovery after high rpm runs or stable readings on hot days. I never got that.

I also broke a new engine in a couple of years back with Penzoil & then after 1,000 miles went to Mobile 1. No problems so far with cam shaft wear. That usually shows up real fast on the drain plug. I am definitly a Mobil1 believer and I don't see any reason it would not work in the LBC's we own. Many owners reported excessive leaks when Mobil1 was used and that is probably due to the thinner weights. Try the 15w-50 and this should improve your results , although if you have an oil leak thick oil does not fix the problem nor should it.
 
I spoke to a Lucas Oil representative today regarding this problem. They have been promoting their oil stabilizer as an assembly lube for a couple of years. The feedback has been excellent. They have more recently introduced a high performance assembly lube that is supposed to be better yet.
They also market a 15w-40 oil that is rated for diesel engines which is also receiving good feedback as a break-in oil.
I've been using their products for several years with what seem to be good results. I won't know until the motor comes out.
I hope this is a cure for this problem.
 
So after absorbing this information it seems like most of the concern is for rebuilt engines? What about the 99% of us who have engines that have been rebuilt a while ago, or who have never had a rebuild? Is there a solid recommendation for exactly which oil and wieght that should be used ? I have a 72 TR6,about 100,000 miles, rebuilt at about 80-85,000 miles. What EXCACTLY should I use?
 
I run Mobil 1 5-40 diesel rated oil in my 6. The engine was rebuilt about 15k miles ago. Pretty much any diesel rated oil should work with a flat tappet engine because it has the Zinc needed to provide adequate sheer protection. Typical diesel engines have a 20:1 compression ratio and the wrist pins are apparantly a problem if you don't run oil with enough Zinc. Another option is to run some camshaft lube in your regular gasoline rated oil (valvoline 10_40 or 20-50 for example) by adding a 4 oz bottle of GM camshaft and lifter prelube (PN 12345501) when you change oil. I'm currently rebuilding an AH 3000 engine and the plan is to break the engine in using a conventional quality motor oil + the GM camshaft prelube for a few thousand miles. Once we're satisified the engine has been properly run in, we'll convert to a Mobile1 diesel rated oil. Since the seals are all new it should be OK as far as leakage is concerned.
 
Some of this has been blown totally out of proportion and is unecesarrily alarmist.

Another factor that has not been discussed here is the fact that for a while there were a bunch or very poorly made tappets being sold. There was a glut of cheap asian produced solid lifters that flooded the market a few years back (2000-2001) and caused all sorts of cam failures that had nothing to do with the oils used. This was not only a problem with our cars but hit the muscle car crowd pretty hard as well. The muscle car crowd uses solid lifters in their very hot street and race motors. Otherwise most of them have switched over to hydraulic lifters for the majority of applications.

The problem of bad lifters has been pretty much worked out. I have personally seen two sets of bad lifters (one set being in my own engine). In both cases that I witnessed the lifters/tappets were replaced with higher quality items that were tested for appropriate hardness (Rockwell) before sale. In both cases I witnessed, the lifter began to disintegrate but the cam lobes were completely unharmed.

The reduction in zinc levels in oils can have an effect on the ultra high performance engines with very radical lift cams and the resulting higher pressures they develop at the cam/lifter interface. Castrol has stated publicly that their oils, especially 20W50, are fully backward compatible and more than meet the needs of solid lifter engines that are still primarily as the manufacturer intended. They also say that current oils are tested to a higher degree than older oils which adds to their confidence that their modern oils are just fine in our old technology engines. So they are saying that stock engines should have no fear of the reduced zinc levels. (As long as the rest of the internal engine parts are up to snuff, but that is not the oil companies problem)

Really, any of our cars that are still streetable, even with higher lift cams, should encounter no problems. Engines built with truly radical camshaft lift numbers, essentially cams designed for racing, should use oils designed for racing as they still contain the appropriate levels of zinc. If you are feeling especially worried about it then you can also use racing oils in your street car to maintain those levels of zinc or add some cam break in lube with every oil change. Though the effectiveness of the latter is debateable as to just how much the break in lube can mix with the oil and provide a consistent form of protection.

The reason zinc levels have been reduced is that they have found the zinc to have a detrimental effect on catalytic converters and thus the content of engine oils become a contributing factor in emissions. Several diesel oils still contain zinc but they are slated to cut back on zinc content as well again due to tightening emissions regulations. Which will eventually leave racing oils as the only oils available that do not have to worry about the emissions ramifications.

Bottom line, good old Castrol 20W50 should still serve well with no problems. But if you are worried, then by all means use Racing formula oils, some diesel oils will work just fine as well or try adding some cam break in lube with each oil change. Peace of mind can often be worth the extra money.

/ubbthreads/images/graemlins/cheers.gif
 
GM also supposedly has an oil additive that has the right stuff. My question is, is this only a concern for an engine during break in or well after that too?
 
[ QUOTE ]
Some of this has been blown totally out of proportion and is unecesarrily alarmist.

...

Bottom line, good old Castrol 20W50 should still serve well with no problems.
/ubbthreads/images/graemlins/cheers.gif

[/ QUOTE ]

What about Castrol 10W40? This is what I usually use.

This reminds me of what happend in the UK when they stopped selling leaded gas. Everyone was in a panic about getting the hardened valves (or whatever it was), but over here in N.A we've been using unleaded gas for a long time with the regular valves without any problems.
 
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