OOOPS!!Wrong oil!!!
Safety Car
Joined: Jan 2005
Posts: 3,675
Likes: 58
From: Hayward (Bay Area) CA
Read the manual. It says 10-30 is just fine, or can be used as a substitue for 5-30, when the weather is below freezing. Check out your Vette book. You made no mistake... Its just fine. Dont worrry about it. Infact, I did my first oil change since I bought the car. I put in Mobil 1 10W-30W.
Race Director
Joined: Aug 2000
Posts: 11,470
Likes: 762
Originally Posted by Biggieflan
I was doing the routine oil change on 97' Coupe 6spd, everything was going normal as always during an oil change. The only problem was when I was cleaning up and throwing away the oil bottles I noticed the viscocity of the oil I got was 10w-30....I had already finished the oil change and started the car...My question is, will this affect the engine? It seems to be a little slugish. And should I perform an engine flush before I change the oil?
the frickin' car is toast. you better sell it fast. as a good friend and co-forum member, i'll take it off your hands for $50. 
seriously, nothing to worry about -
Le Mans Master
Joined: Mar 2002
Posts: 6,885
Likes: 2
From: Corpus Christi TX
Originally Posted by Dave68
According to a Mobile 1 tech support engineer I spoke to, using 10W-30 is NOT advantageous during hot weather compared to 5W-30. He went on to say that Mobile has found that most engine wear occurs at startup - even when startup temps are in the 70s. (0W and 5W oils flow better at startup temps.) In fact, this Mobile rep. told me he is using 0W-40 Mobile 1 in his vehicle (Texas). The big fallacy that spreads quickly is that 10W-30 protects better than 5W-30 (same brands). This is absolutely false. In fact, one of the best oils for any part of the country is German Castrol 0W-30. The "30" indicates a measure of high temperature protection and the "0W", the low temp flow ability.
Bottom line: If you have installed 10W-30 by mistake, it probably doesn't buy you much in the long run to drain it now, but at the next oil change be sure to replace it with at least a 5W-30 synthetic oil. Other good options are the Castrol (European) 0W-30 and Mobile 1's 0W-40. In the long run, these are better choices than a 10W-30.
Bottom line: If you have installed 10W-30 by mistake, it probably doesn't buy you much in the long run to drain it now, but at the next oil change be sure to replace it with at least a 5W-30 synthetic oil. Other good options are the Castrol (European) 0W-30 and Mobile 1's 0W-40. In the long run, these are better choices than a 10W-30.
translation:
mobil over produced 5w30/0w40 and has a tremendous surplus
haha, just kidding. I run redline 10w30 here in DFW all year long. Just had a compression test done on my motor and it's as strong as ever. 33K miles and tons of rev limiter-kissed 1/4 mile action.
