Oil weights and grades
TECH Fanatic
Joined: Apr 2005
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From: Just This Side of Damnation
Originally Posted by custom 68
Why is there a time limit on oil say the 6 months? I mean it doesnt go bad. Is it a moisture thing?
Dave
Dave
The time period it takes to use up these additives varies depending on the way you drive. Short trips that don't let your oil heat up and drive off the moisture uses these additives up quickly. Longer drives don't.
Less immediately urgent but still important is the fact that as you drive your car there are places within your engine that produce localized hot spots. Those hot spots in particular, and normal operating temperatures in general, drive off from your oil the lighter and more volatile portions of your oil. As this happens your oil gets thicker. All oils do this but the synthetics do it less than conventional oils.
Add the two together and you get a limited useful life. Your mileage may vary.
Originally Posted by Tranzor_Z28
I like that cowl! 
So how's visability with it? I've been looking at getting a 4" cowl hood, actually...
So how's visability with it? I've been looking at getting a 4" cowl hood, actually...
11 Second Club
Joined: Feb 2003
Posts: 5,524
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From: The South
Originally Posted by spy2520
Visibility is decent. What i like to call "active" visibility because sometimes you gotta move around to see. For the passengers it is a complete obstruction but i dont care. Definitely an attention getter. People keep asking me if it is functional, and if i got a big carb...i think thats funny.
TECH Senior Member
Joined: Nov 2001
Posts: 7,234
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From: Mississauga, Ontario
The three month rule is also something that's old school. My mom does short trips in her car and I've got her on a one year oil change schedule. She only does about 5k during this time. I've got her car running GC 0w30 too.
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Joined: Mar 2004
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Originally Posted by Tranzor_Z28
IMHO, you should really extend that drain interval... using a good synthetic for only 3 months or 3000 miles is like throwing good oil away. Unless its under very harsh conditions (like a mostly track driven vehicle) in which case the use would mandate a unique interval.
For comparison, I go to the track at least twice a month during the season (probably around 12-15 trips to the track in a year, around 60-70 or so 1/4 mile passes) and I change my oil & filter once before race season, and once after... so every 6 months. And my oil comes out looking great even after 6 months of fairly harsh use. In fact I could probably go longer, and just change the filter.
And I'm just using the lowest cost oil Amsoil sells, which is their XL formula. If I used their Severe Service 0w30 or 20w50, I would go with 1 year intervals, change the filter at the 6 month mark.
Point is, synthetic oils are getting better and better, really making the 3 month/3000 mile interval obsolete.
For comparison, I go to the track at least twice a month during the season (probably around 12-15 trips to the track in a year, around 60-70 or so 1/4 mile passes) and I change my oil & filter once before race season, and once after... so every 6 months. And my oil comes out looking great even after 6 months of fairly harsh use. In fact I could probably go longer, and just change the filter.
And I'm just using the lowest cost oil Amsoil sells, which is their XL formula. If I used their Severe Service 0w30 or 20w50, I would go with 1 year intervals, change the filter at the 6 month mark.
Point is, synthetic oils are getting better and better, really making the 3 month/3000 mile interval obsolete.
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Joined: Nov 2001
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From: Mississauga, Ontario
Originally Posted by Hot02SS
I dont care. I still do it every 3 months or 3000 miles, no exceptions.
It's your dime, however you would get the same levels of engine wear if you went 6 months/6000 miles. I've got the oil analysis results which prove this.
