All through the Clean and Rinse Phases I used dino oil, when I went on my 1st Maintenance Dose for 3000 miles I used Pennzoil Platinum III which is a Group III motor oil so it is not 100% synthetic, for my 2nd Maintenance Dose I put in Amsoil 100% synthetic which is a Group IV motor oil and now I am having some leaks near the rear main seal which was replaced 23,000 miles ago, so for basically 13,000 miles I had used a Group III oil, in 156 miles I have had to add about 6 ounces of motor oil, should I dump this oil and go back to Group III or since I have 6 quarts left keep topping off and on my next oil change go back to Group III oil's maybe with the old seals on an engine with 357,000 miles it might be better, thanks for your help.
Well, as far as synthetic oil is concerned on high mileage cars I have always been told that the reason why seals might start to leak is because the synthetic oil tends to "dry" them out. If that is the case then I would definitely dump the oil and go back dino oil and add 3oz of auto rx as a maintenance dose.
Go back to non synthetic oil and that should stop the leak if the seal is not damaged. I had to go through 3 oil changes with Dino oil before the leaks stopped.
Jim, when I went out tonite I checked the oil as I had been driving around a lot today and the oil level was fine, I will have too get the car up on the lift and take the flywheel cover off and see what's going on, now that the weather is warmer I am going too start driving the car too work everyday and see how things are going, I changed the oil last Sunday and did not drive it much meaning there was a few days that I did not take the car out, who knows maybe with the miles I have on the car the PCV can only handle so much, I remember looking at the breather and it was a little colored so maybe the foam element in the breather is getting a little clogged, I may need too change it, I think that I have another one so I will put it on tommorow, the car is not smoking on startup, this leads me too believe that if it sits too long then some oil may seep into the combustion chamber, I am only on my 2nd Maintenance Dose so it may take some time before everything is where it should be, the other issue I have is a slight coolant leak on the lower radiator hose, this started happening after I took my heater core out too get better acces to my spark plugs, at the time I put in a stewart thermostat that had 3 holes drilled in the thermostat too relieve pressure but it ran too cool so I took it off, I will need too drill 1 hole in the thermostat and see how it goes, I also changed my intake manifold so I no longer have an EGR valve so maybe some more pressure in the engine,so for now I will just keep an eye on the oil level and see how things go. I also know that not driving the car much is bad for the seals.
I checked the oil level again today and it is fine, I will just keep an eye on the oil level from time to time, also noticed the oil color on the dipstick after 300 miles into 2nd Maintenance Dose is somewhat of a amber gold color, a little bit darker than when I last checked it meaning the oil on the dipstick does not have a clear color so maybe some cleaning going on who knows,but time and mileage will only tell.
