Best Oil to Use?

[TopsailBeach]

I know there are plenty of threads about this, but I'd really like to know what folks are using....my 1986 911 has been fed Castrol 20w50 for the past 15 years, and runs just fine, but is consuming oil at 1 qt/600 miles with a little smoke on decleration. I've read that Shell Rotella T 15w40 is a good heavy duty oil to use to reduce consumption and ash, but I'm thoroughly confused. I hate to change now, but I'd like to do whatever I can to postpone the inevitable top end rebuild. So, what do you use, and why?

[Doug Zielke]

Your 3.2's valve guides are shot, A. J.
Experimenting with oil isn't going to fix them.

(Rotella T is an excellent oil, intended for service in Diesel engines, but also good in gasoline ones.)

[TimT]

I use rotella in my pcar... lots of track miles..no apparent probs

[TopsailBeach]

I'm worried that the valve guides may be going, but I'm not ready to spring for the topend job just yet. The fellow who has worked on the car for the past 15 years tells me that the guides are okay, that it is probably running a little rich, but is still in the spec range for oil consumption and has been that way for a while.

Anyone else using Rotella with good results?

[stormcrow]

I also use Rotella 15 W 40 in my 78 SC Targa. In the past before Rotella, I used Valvoline 20 W 50. At every oil change, I would check the plug and there would be a fine coating of black on the magnet - sort of like sludge - not really sure what it was but no particulate matter. Anyway, since I made the change (this is about my 4th oil change using Rotella) no more black coating - clean magnet.

As far as oil consumption goes, it's all a matter of how hard you drive your car. When I did my first DE a couple of weeks ago, I used a quart of oil at the track event - two days of hard driving.

Normal driving (what's that) I have gone over 1500 miles before adding a quart. What I did notice is that the more high rpm shifting I do in the lower gears (1, 2 and 3rd) , the more likely my oil consumption will go up. I also noticed my valves quited down a bit (they now need adjusting) so that made me happy.

Steve

[usurpah]

I also use Rotella 15 W 40 in my 78 SC Targa. In the past before Rotella, I used Valvoline 20 W 50. At every oil change, I would check the plug and there would be a fine coating of black on the magnet - sort of like sludge - not really sure what it was but no particulate matter. Anyway, since I made the change (this is about my 4th oil change using Rotella) no more black coating - clean magnet.

I have the exact same sludge...also with Valvoline 20w/50.

Question is, is it better that I'm taking the sludge out of the engine every oil change...or is the Valvoline responsible for that sludge...?

- Eric

[stormcrow]

It could be the difference in the make up the oil that probably eliminates it.

Steve

[McDaniel]

Ashland headquarters is located here in Kentucky.
This link might be helpful to you with makeup of product

http://msds.ashland.com/