Ok, Lets Talk Oil!

[DohertyCM]

ALRIGHT...GET YOUR DUCKS IN A ROW>..

I have a 74 911 2.7 CIS.....

What is the best oil to run in my motor......

Standard or synthetic?

How about grade and weight?

What about brand?

Now I have downloaded the OIL BIBLE and gone thru that...
BUT I want to know from the rest of the porsche community.

What are the downfalls of Synthetic? Will it leak more?

My mechanic seems to think so....This needs to be addressed correctly because 14 quarts of oil is nothing to make a mistake on with the prices we have these days.

What say you ?

[gduke]

Royal Purple Racing 41

It's 10w40

[Steve@Rennsport]

Originally posted by DohertyCM
What is the best oil to run in my motor......

Standard or synthetic?

How about grade and weight?

What about brand?

Now I have downloaded the OIL BIBLE and gone thru that...
BUT I want to know from the rest of the porsche community.

What are the downfalls of Synthetic? Will it leak more?

My mechanic seems to think so....This needs to be addressed correctly because 14 quarts of oil is nothing to make a mistake on with the prices we have these days.

What say you ?

Great question!

Many variables at work here that frame the answer:

1) Quality & type of seals, gaskets and O-rings used in your motor.

2) Type of use

3) Local temperature ranges

Generally speaking, GOOD synthetics keep the engine's internals far cleaner and in some cases, exhibit less wear. Some of this depends on oil temperatures, too.

I'd recommend:

Mobil 1 15w-50
Kendall GT-1 20w-50 (non-synthetic)
Valvoline VR-1 20w-50 (non-synthetic)

Change the oil every 3K to 4K, use Mahle filters, use a proper front oil cooler and that 2.7 will last a very long time.

[real550A]

I ran Mobil 1 15w50 in my 3.2 for 3 years with zero leaks ever.
That said, I'm going with the Kendall 20w50 in my new E 2.4 when it's done.

[Hugh R]

Calling Lubemaster

Castrol GTX 20-50 for my socal car.

[gr8fl4porsche]

Originally posted by DohertyCM
[B]
What are the downfalls of Synthetic? Will it leak more?B]

Possibly.

I have had small to large leaks erupt on several mid mileage cars of various makes when switching to synthetic.

Could be coincidental, but I don't use it except in newer motors. Lots of manufacturers still recommend dino oil or a blend.

[DohertyCM]

I use the GTX 20w50 also along with the Lucas oil treatment. What a difference the Lucas made!. But believe it or not the Castro didnt rank very well. Thats why I posed the question.
Lots of good input so far, keep it coming.

[Dan in Pasadena]

Originally posted by Hugh R
Calling Lubemaster

Castrol GTX 20-50 for my socal car.

I'm using the same in my 2.7. Unfortunately, I do not have an oil cooler at all!

Steve @ Rennsport, Just curious....you recommend Kendall over Castrol, any specific reason?

[1982911sc]

I used to run Dino...castrol 20-50...my wrench recomended synthentic especially for DE and hard driving....I switched and my car runs about 5-10 degrees cooler...no leaks or anything...but I really wonder if it is worth the extra cash as I change my oil annually with less than 3000 miles per year...good question all together.

[aigel]

Sythetic is the way to go. But the leaks are a fact, your mechanic knows that from experience. Only if you just resealed the engine would I recommend you switch to synthetic. Even after partial reseal on my engine, I didn't dare.

George

[greg bradbury]

Valvoline GP50 which is a 25W50. mechanics advise

[David E. Clark]

I use Castrol GTX 20/50 High Mileage in my 1973 2.4 MFI. Short trips and idling make the car run rich so I'm looking for a little more protection and help in keeping the seals in good shape. That's what I'm hoping anyway.

[rfuerst911sc]

I have run 20w50 Valvoline,Kendall,Shell conventional all with what appears to be good results. My last oil change ( last week ) I went with 15W40 Shell Rotella T dino oil as there were quite a few posts on Pelican that recommended this oil. It was suggested that the 15W40 would run cooler, time will tell.

[charleskieffner]

our train of thought after running castrol gtx with no problems, is to give our spoiled baby mobil one. motor just resealed 3 days ago, and we figure what the hell, give it the best and see what leaks. also we are going to run oil for 7500 miles while changing filter at 3750 miles. it is being used for DE's and trips w/g/friend only so it will take awhile to rack mileage on. ran the snot out of it yesterday after changing g-50 over to mobil one syn and it shifts even better. after also spending 3 1/2 hours with mega buck mega pressure steam cleaner at hunting buddies shop on rack, it runs a hell of alot cooler than it ever has after cleaning/degreasing from bow to stern. pain in the keester but well worth it! cosmoline should be banned from the planet. used restaurant degreaser and wd-40 (ie. took a bath in it) degreaser safe for stainless steels alum mag etc. bought at smart final. $20 bucks for 2 one gallon jugs which was injected by steam cleaner.

[1982911sc]

The meth must be flowing pretty freely in Arizona! Just kidding Charles...I too saw the temp drop with synthetic.

[Steve@Rennsport]

Originally posted by Dan in Pasadena
I'm using the same in my 2.7. Unfortunately, I do not have an oil cooler at all!

Steve @ Rennsport, Just curious....you recommend Kendall over Castrol, any specific reason?

Hi Dan:

First,..You need an oil cooler on that 2.7 if you expect it to live,....

I do not use, nor recommend any Castrol motor oils due to camshaft wear issues. I simply cannot take the chance anymore with customer engines.

YMMV, of course,....

[Wil Ferch]

Shell Rotella-T synthetic ( class 111 synthetic..doesn't leak)..5W-40


Wil

[swa911]

Castrol 20-50

[pwd72s]

Hell, even my lawnmower uses synthetic!

[kach22i]

Originally posted by pwd72s
Hell, even my lawnmower uses synthetic!

I took that crappy fake stuff out of my 911, I had a bottle left over. I put it in the old lawnmower - only thing it's good for.

Synthetic for new and newly rebuilt engines.

Dino for the old guard.

Looking at trouble if you disregard my words.