Can I use 10w-30?
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Former Vendor
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From: Tampa FL
St. Jude Donor '07-'08-'09-'10-'11-'12'-'13-'14-'15
Can I use 10w-30?
I know the manual and the cap say 5w-30 but can you use 10w-30 safely in temperatures from 40-110 degrees? I am in NC and it gets cold but not really cold. I am asking because I realize that the oil is probably a little thicker since it is a higher number and my ported and shimmed oil pump pushes 45psi under load and 75-80psi under WOT. Would it cause the oil pressure to be too much with thicker oil? This is probably stupid but I just want to make sure?.............no one ever accused me of being smart............oh yeah, except my Mom 
Thanks Mom 
Thanks Mom
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St. Jude Donor '16
I run 10w30 in all mine...
Thread Starter
Former Vendor
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From: Tampa FL
St. Jude Donor '07-'08-'09-'10-'11-'12'-'13-'14-'15
Originally Posted by budmont
Main difference is when its cold not hot
Cajun
Drifting
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From: hamilton nj "Life's tough......It's even tougher if you're stupid."-John Wayne
Originally Posted by joghotrod
It will flow just fine. The 5w30 will flow slightly better but at that temp. it won't matter. Jimmy
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Melting Slicks
Joined: Apr 2002
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From: Clever, MO aka SOMO
I've always used 10W30 Mobil 1 here in San Diego county. I always let me car idle for a few minutes and let the oil temp reach at least 100 deg. before even backing out of my garage.
Melting Slicks
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My stroker motor uses so much oil I am going to a DINO oil for a while to try and use like a 10-40 valvoline and see how it looks, we have noted on some of the bigger cams etc in the big stroker motors that 0-30 and even 5-30 synth oil does not seem to be working as well as noted on cam bearings etc, I will try just to see if the heavier natural oil will slow down so of the usage and what affect it has on the dyno--as far as 10-30 I have always run 10-40 in the hot summers here and 5-30 in the cooler months--
Team Owner
Joined: Sep 2003
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From: Raleigh / Rolesville NC
Let the oil warm up to 80+ degrees before you drive off and you will be fine.
I use 15-w-50 and let the oil warm to 100 before I drive anywhere. But then again my car is almost only a DE car and frequently see oil temps in tht 250 range. I also have an oil cooler and a 3 qt accusump to keep the oil DOWN to 250 and accusump keeps the engine well oiled.
I use 15-w-50 and let the oil warm to 100 before I drive anywhere. But then again my car is almost only a DE car and frequently see oil temps in tht 250 range. I also have an oil cooler and a 3 qt accusump to keep the oil DOWN to 250 and accusump keeps the engine well oiled.
Le Mans Master
Joined: Sep 2003
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From: Just a little outside San Antonio, Texas
Originally Posted by ccajun4real
So lets say my car sits at work all day and it is 45 degrees outside. Do I risk the oil not getting up into the engine as fast?
BTW, how's Hope Mills? I used to live there at Camden and Rockfish Roads back when Hope Mills was a sleepy little town? Can you still fish in the city lake?
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Former Vendor
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From: Tampa FL
St. Jude Donor '07-'08-'09-'10-'11-'12'-'13-'14-'15
Originally Posted by ArmyVette
You're fine using 10W30 in your temp range. Just remember to let the engine (and tranny) warm up to normal operating temps before driving away.
BTW, how's Hope Mills? I used to live there at Camden and Rockfish Roads back when Hope Mills was a sleepy little town? Can you still fish in the city lake?
BTW, how's Hope Mills? I used to live there at Camden and Rockfish Roads back when Hope Mills was a sleepy little town? Can you still fish in the city lake?
The dam on the lake broke last year and it is a dry bed with a small river flowing through now. LOL Of course it will take the town of Hope Mills three years to repair that. It took the damn and the hardened bed all with it. Here comes some higher property taxes......like they dont stick it in you already.
Racer
Joined: Mar 2003
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From: Southbury CT
Originally Posted by ArmyVette
You're fine using 10W30 in your temp range. Just remember to let the engine (and tranny) warm up to normal operating temps before driving away.
Race Director
Joined: Dec 2000
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From: San Diego CA
I spoketo a Mobil 1 tech rep not too long ago and he didn't see any compelling reason to use 10W-30 in a C5. In fact, he lives in Texas and is using 0W-40. His explaination was that most engine wear occurs at startup, even at 70 degree startups, so a 0W or 5W multiviscosity oily is better for the life of the engine. After speaking to the tech rep, I decided to toss all ideas about using 10W-30 oils out the door. Of course, 0W-40 sounds like a very good idea now.
BTW, one of the CF members and resident oil guru, Patman, uses a European-grade Castrol 0W-30, since it outperforms most other oils in an LS1.
BTW, one of the CF members and resident oil guru, Patman, uses a European-grade Castrol 0W-30, since it outperforms most other oils in an LS1.
Race Director
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From: Guelph, Ontario
Yep, I like the German Castrol 0w30 because it will flow extremely well in the cold (and I drive mine in the winter and it's parked outside overnight) but yet it's almost a 0w40, since it's viscosity at 100c is 12.2 cst which is almost a 40 wt. The oil analysis results I've gotten with this oil are very very good.
