Player0

Because I don't read carefully enough, I accidentally added two quarts of synthetic 5w20 to my dino 20w50 in the 944 when doing the last oil change. The wife's SUV takes the thin stuff. All oil was Castrol.

Is there any reason I should drain all this perfectly good oil and take it to the recycle bin? I hear that mixing synth and dino might cause extra sludge build up. I also worry that the 5w20 is leak out of every seal I have. Or... does it just mix with the 20w50 and make it a bit thinner. Given than winter is approaching, maybe that's not such a bad thing?

Anyway, should I just run it, maybe change it early say 2000 miles or something? Any other advice here?

Going to have to get some big orange stickers or something so I don't do this again.

ZR8ED

Is the 44 a track car? weekend street cruiser or dd?
Track car..dump the oil.
Hard street driving...dump the oil
Easy street driving..drive the car, change the oil ahead of schedule and give yourself a slap on the wrist.

morghen

take it out, put a fresh one in...castrol is cheap anyway.

odurandina

no.

don't mix ultra thin with thick summer oil. good mixes of oil...

and that dyno oil can easily cause sludge buildup regardless.


winter in cold climates: straight 0w50 or a mix of 0w50 with 5w50, 10w40, or 0w40.


winter in the sunbelt:

straight 0w50 or 5w50.... or a mix of straight 0w50 with 5w50, 10w40, or 0w40.


fall; 0w50/15w50 mix or 5w50/15w50 mix.


summer; 15w50.


btw,

i wouldn't run 20w50 (20w55) unless i doing saturday driving at the track.

John_AZ

Basic chemistry. If you mix a thin weight 5w-20 with a thick 20w50 you get +-13w35 to 15w40 (2 mix with 4).

If this is the weight you want in your '86 turbo for the winter you are OK.

Castrol and other oil companies make semi synthetic oils. Mix synthetic and conventinal.

http://www.castrol.com/castrol/gener...tentId=6003233

I use 20-50 Castrol GTX year round in AZ. Summer temps of +100* average 109 times a year.

John

bordin34

Dont worry about it if anything the thinner oil will help the car start and protect a cold engine in the winter.
I personally wouldnt run anything as thick as 20w-50 when it is cold out.
In the summer I run rotella t5 10w-30, in the winter I use full synthetic rotella t6 5w-40. I used rotella in everything I own its additive package is far superior to a normal motor oil.
My car has around 100k miles on its original engine and doesnt leak oil even with the synthetic.

333pg333

10w/30 in the Summer? Interesting...

bordin34

Thats what I normally do but it depends on what I have on hand. Right now I think I have 4qts Rotella T6 and 2qts Rotella T5 and I use T1 to top it off. So I'm around 7w-37

Player0

In hindsight, I don't know why I added the 20w50 either. I meant to get a different oil for the winter. I had intended to do a few track days this summer which is why I bought the 20w50. Plus I have just spent dozens of hours replacing every single little oil seal and cleaning years of burnt sludge off of things so I guess subconsciously I just didn't want it to leak anymore.

I'm in Boston and want to drive it a little on the warmer, nicer days in the winter. It will be above 0F but 20W50 is probably a bad idea. I don't want to start another oil war thread, but will go read one of the other ones.

I'm a little gun shy on synthetics since the last 'porsche mechanic' put synthetic 5w30 in to it and charged $180. But it just leaked out everywhere. I'm particularly troubled by the rear main which may or may not have been leaking. I'm hoping it was the cam tower gasket causing the mess back there.

Anyway, mine might be a little too much like 'swiss cheese' for a thinner synthetic.

odurandina

if you want the perfect oils to run.

Mobil 1 0w50 Racing Oil or 5w50 Rally Oil winter.
Mobil 1 5w50 Rally Oil sping/fall.
Amsoil 15w50 summer.

i preach thin oil all day. and during the winter, if you don't want to spend the extra cash to get Mobil 1 0w50 or 5w50, then run some 10w40 or 0w40..... it's not the perfect oil to be running in the car, but the cold start protection is there... i've been running my engine hard for 5 years using this model and @ 160 k miles the engine still doesn't burn hardly any oil and pulls hard... i wouldn't recommend putting in 30 weight oil. dino or synthetic.... why ? becuase all the cold start protection for our particular engines (and the only advantage of a 30 weight oil) is already present in Mobil 1 0w40, 0w50 and 5w50 (and other brands') synthetics.

for the winter, Mobil 1 0w50 Racing Oil is the best protection money can buy.




update;

here's to fine wine and the world's best oil... but $16.30 is a bit steep.

http://www.mobil1racingstore.com/mo1ra0w.html


$13/quart...

http://www.nissanraceshop.com/produc...Fao7OgodHjwALQ



gasoline and oil prices are insane.

maybe the president needs to go.


.

bordin34

Or on a budget Rotella will work just as well and it has a normal detergent package.

bonus12

[quote=

Fintro11

Don't mix oils, the chemical reaction can lead to some pretty nasty stuff. Drained a gear case where a person mixed oils in the barrel it was boiling... Better off draining it

FRporscheman

You're fine. The key is oil pressure. If you have more than 2 bar at all times then it's OK. It's best to keep it over 1 bar at the very minimum. Mixing oil is a common practice.