When you purchase that new OLD vette, is there any advantage to multiple oil changes to clean it out a bit? Most of the time after I change the oil in my other cars, it continues to look clean and fresh on the dipstick for awhile. When I changed the oil in the vette, it didn't take long to look dirty on the dipstick. This is also the first time I have used Mobil one. (I would guess it should look like regular oil)

Who knows what kind of maintanence these cars have before they end up in our hands, right? Any thoughts?

 

I agree. I changed mine after first 1000 miles of MY driving it.

 

Some people use SeaFoam in the oil and run it for a couple days or so and then flush the oil... But be aware that cleaning up whatever sludge may be in there can also cause leaks to be exposed... I 've never used it but I have read Mobil 1 may have some extra detergents and that will also cause the darkness you are seeing - in which case it may very well need to be changed sooner...

EDIT: Of course there is no reason you need to use expensive oil like Mobil 1 for flushing - or even at all as long as you maintain your car well - no matter what anyone else may say - no car should go more than 3k without a change - I believe my fiance has already ruined her Tiburon by listening to her dad that believes in the manuals... Now I do her oil, but before the first time (that I did it) it got to the point where the engine strained real hard and sounded real bad (not that these "rice burners" sound good anyway) - after the change it was a night and day difference in performance but not what it used to have... - - -

but again - look through the threads on oil leaks that start after switching to a synthetic oil or after using detergents - if the gaskets and such aren't sealing right on their own you may very well expose a LOT of leaks... I know...

The bottom line is you may need to change it sooner now, but switching back to a regular oil - perhaps Castrol GTX or something may keep the oil cleaner and have less risk of exposing leaks... I will be going back to Castrol GTX tomorrow as I switched to Castrol Syntec last time and the next day I had lost a LOT of oil (typically there would never be any oil on the ground) - but after the change I could park for a few minutes and have a noticeable amount under the car... it seems to have slowed down a little bit now that it is at midway on the dipstick. I will see if switching back helps anything - then I will re-post...

 

There are certainly no disadvantages to frequent oil changes when dealing with an unknown. If it darkens quickly, keep changing it until it ceases to do so and then go on a reasonable schedule. If you seriously suspect neglect and/or are sure of it, run a couple of changes of good diesel oil through it such as Rotella or Delo 15w40. These are higher in detergent content and are excellent for cleaning. Don't do any extreme or extended high RPM driving while using them though. At higher RPMs, higher detergent oils tend to foam more and this could lead to a momentary breakdown in lubricating abilities during such periods.

 

There are no real disadvantages to changing it often, but you could be wasting money by doing it too often without knowing of what problems might be there. Also, just because it turns black doesnt mean there's a major problem.

If its a 92, then it should have had Mobil 1 in it, in which case it shouldnt be gunked up internally (which'll make the oil turn black quick). I'd recommend changing out the M1 within 3000mi and no further, and be sure to use a good filter. If you don't drive it that much, be sure to change once a year at least. Do that religiously until its not turning black, then you can go longer (5K range if the mileage isnt too high).

If you want to be sure, one way or the other, send your oil off for testing and you'll find out what problems might be in that engine.

I always do every bit of routine maintenance as soon as I get any new car, you never know how good the previous owner treated it.

 

I don't disagree with any of the above, and I'd say it can't hurt to do a couple of "early" oil changes on a good, old, "new" Corvette that you buy.

However, recognize this: different engines are designed, engineered and built differently (no surprise there). Some engines, from brand new, after a couple of hundred miles on "new oil" will look dirty. It isn't the condition of the new engine, it's the design and execution.

I had a car that, for the 175K miles I owned it (from new in '98 until '03), when you put in new oil (especially synthetic oil), you could take out the dipstick at 1000, 3000, and 5500 miles and it looked almost new. So close in fact that it was tough to tell, visually. I've never had a car like that one before or since.

But I'm fairly certain there are others out there like that one.

 

I also agree.

When i got my 85 last Oct,the first thing I did was change the oil & filter,use a can of motor flush for 20 minutes and changed the O & F again the same day.And again after the oil got dark( approx 400-600 mi).

I usually get a new car every 4 years(Last was 03 Honda S2K) and when I do,I get several new oil filters in the deal and go home and change the O & F.Even new machines may have a little metal debris in the engine.

My theory is Oil is cheap,engines are not.

\DB2
Carolina