T.Williams

Im actually posting this for a buddy of mines 98 ls1, he bought the car about a month ago and we brought it to my house that day and put it on the lift and changed the oil, and the car was totally dry not a leak anywhere with 150,000 miles on the clock. We dont have any idea what kind of oil the previous owner used. I have always ran royal purple full synthetic 10w 30 in mine, so we done the same on his. We put the car back up on the lift yesterday for the first time since the oil change and found that the oil pan seemed to have a pretty good leak all the way around the seal, and was blowing back on the trans. pan a little. The only thing that really came to mind was maybe that the oil that was used by the previous owner prob. was not a full synthetic so it was a little thicker weight oil. I guess that royal purple being full synthetic manged to find its way out the oil pan gasket. Anybody got some ideas or what to do, or just go ahead and pull the pan.

jsteele90

iTrader: (13)

switching to a synthetic in a car that has had regular oil ran in it will usually result in leaks. pull the pan if you want " have fun". or just switch back to regular oil at the next oil change. or maybe the owner cleaned the bottom of the motor really well before selling it!!

T.Williams

What would be a good oil to use after using royal purple.

O2Form

Try some Pennzoil 10-30 high mileage oil.

BIG_MIKE2005

iTrader: (116)

I really dont see why everyone runs synthetic on these cars. Good ol' 10w30 dino oil does just fine. I have ran Castrol GTX 10w30 year round in my car & when we pulled the heads at 100k miles it still had stock cylinder cross hatchings & no ridge at the top of the cylinder either. Hold oil pressure great & doesnt cost me $70 a oil change either.

Toss some regular oil back in it & keep on driving.

redbird555

iTrader: (14)

From the reviews and tests I've seen done on royal purple you may as well just use diesel fuel to lubricate the motor the uoa's show that RP is terrible after 1000 miles. If your going to run dino oil you cant go wrong with just about any good brand. Pennzoil yellow bottle is good stuff and I personally favor the 10w30 valvoline vr1 oil it has a little bit higher zinc ~1360ppm iirc as opposed to ~900ppm that regular oil does

TheSilverOne

iTrader: (22)

Yeah at that mileage going from regular oil to synthetic, the gaskets will definitely leak. With my cars that I wanted synthetic in, but had regular oil in before, I converted one quart at a time per oil change. And synthetic oil changes on these cars definitely don't cost 70 dollars

Mr Incredible

ANY modern, name-brand 5w-30 or 10w-30 conventional oil is a good oil to run. Change at 3k-5k miles and don't agonize over it. The only modifier to that would be if you have a built engine that your run the **** out of. They you could go to a 40w without worrying about it.

More expensive is not always more better.

chris95lt1ta

I work for a jiffy lube and I use pennzoil 10w30 high mileage I already have leaks from everywhere planning buying a rebuild kit and fixing it but that's my advice

sleepy_z

iTrader: (8)

I agree...

O2Form

I go 6k on regular yellow bottle Pennzoil, car runs great, doesn't leak a drop and the oil still looks clean when its changed. I may start going 7500, oil has gotta alot better in the past few years. The days of 3-5k oil changes is a thing of the past.

BlackGasGuzzler

iTrader: (3)

Dino oil breaks down faster in high heat conditions. The wear compound is used up a lot quicker as well.

Anything but Royal Purple. That stuff is garbage. Amsoil is my oil of choice, but, if you want something cheaper, Wal-Mart does sell 5 quart containers of Mobil-1 for like $23-26. I run that (even though it's not top choice) when I'm too lazy to go to the Amsoil dealer.

dying at your comment about Royal Purple.

Oil has gotten better, but I've had changes on other cars at around 8k-10k where even Amsoil looks bad. The filter is just as important as the oil. Crappy looking Dino/Synthetic may still retain adequate wear compound after longer oil change intervals, but why risk it? If you run a good filter (high filter rate efficiency) it'll also clog faster and you'll have to do a change.

O2Form

I disagree on the filter, you can easily go 10-15k on the filter.

LS6427

iTrader: (2)

Synthetic oil = joke

I'm creeping up on 160,000 miles on my built 427ci......all its ever gotten was 20w50. Its purring like a kitten, runs great.

All these engines need is regular cheap *** off the shelf oil.

Change it every 3,000....done deal.

PERIOD.

About the leaking oil pan gasket......go around and snug all the pan bolts. My 1998 started showing a little seapage last year and I snugged all of them and then cleaned it up. No more leaking.

.