fi engine oil
I only have about 550 miles on my procharged 408 but I have changed the oil 3 times with rotella 15w40 and I am really considering staying with it because the 10w30 royal P made my last engine totally nasty in the inside.
Ya, I've heard of those stories from using RP and am staying far away from it. I might just have to consider going with the 15w40 Rotella T instead of the 10w40 I guess since many are using with great results. I will have no choice if thats all I can find!
Joined: Jun 2004
Posts: 1,501
Likes: 7
From: Ft. Irwin, California (But Virginia is home)
Been using Mobile-1 10W-30 since the car had 4K miles on it. Running it for 2+ years w/ the turbo and so far all's well. 
Change the oil every 3K miles or 4 months, whichever comes 1st. I use 10W-30 instead of the "factory" 5W-30, cause the 5W-30 increased engine valvetrain noise (synthetic can be a bit "thinner" than comparable non-synthetic oil). Filter wise I run the stock AC Delco or in a pinch a K&N. I would never run Fram or any other paper based filter. Too many nasty stories of the internals coming apart from those filters and F'ing up expensive engines. Just my $0.02. Hope this helps.
Change the oil every 3K miles or 4 months, whichever comes 1st. I use 10W-30 instead of the "factory" 5W-30, cause the 5W-30 increased engine valvetrain noise (synthetic can be a bit "thinner" than comparable non-synthetic oil). Filter wise I run the stock AC Delco or in a pinch a K&N. I would never run Fram or any other paper based filter. Too many nasty stories of the internals coming apart from those filters and F'ing up expensive engines. Just my $0.02. Hope this helps. Hmmmm...you are right. Lots of different opinions in this thread. I read one guy running synth, then another running non-synth. I'm confused again. 
So, let me see if I have this right - synthetic oil runs thinner than non-synthetic, right? I have a 6.0L 408 with a T76, so I should just run non-synthetic 10w30 - 15w40.
So, let me see if I have this right - synthetic oil runs thinner than non-synthetic, right? I have a 6.0L 408 with a T76, so I should just run non-synthetic 10w30 - 15w40.
If you motor was actually built for FI it should of been built loose, meaning it will use more oil than an NA motor due to the larger clearances. The age ole controversy of synthetics vs Dino oil will go on, of course synthetics do have an advantage over regular oil, it has superior heat resistance and less bearing wear, BUT, If you change oil regularly and it is a DD and not a full blown or every weekend track car then regular oil might be right for you. I do use synthetics most of the time but with my loose motor it goes through the oil, and I am a stickler that I change it every 1000 miles or so. This gets fairly expensive. Now for the Dino oil, my dad puts app 1000 miles a week in his van, yes I know this is not a performance motor, but he changes his oil every 3000 miles, he puts what ever the shop has on special, 1st van he had 459,000 miles! Yes almost 1/2 of million miles and it still ran well, no smoke,( I told him he should of wrote to GM) anyway, 2nd van he put 352,000 miles but then he wrecked it. Point is that if he can put this many miles on regular oil, but changing it every 3000 miles then doesn't that say something? Maybe on a particular set up regular oil could be just fine, I would go with a good filter and believe it or not WIX filters from NAPA are suppose to be pretty dam good.
i believe i broke in my motor for awhile with the non S Rotella....now i run the 5w whatever it is Synthetic Rotella. Seems to work well and actually smells pretty good 
i believe my motors built loose and it always looks clean coming out with very minimal metal on the magnetic drain plug.i change my oil ~every 1000 miles as well or less.the oil and filter is like $25 so its cheap but good oil
i believe my motors built loose and it always looks clean coming out with very minimal metal on the magnetic drain plug.i change my oil ~every 1000 miles as well or less.the oil and filter is like $25 so its cheap but good oil LS1 Tech Stories
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Verdad Gallardo Rottela T seems to be a great oil to use. I picked up 2 Gallons of the 15w40 for my next oil change. Built 408 with T76 turbo. If it gets hot in your area (I'm in Central Texas) for the summer, I'd definitely run a thicker oil. 10w30 would be okay to run during the cold months.
On the turbo, I would probably use synthetics due to the heat the turbo produces, but you might want to contact the turbo dealer and ask them, at one time I heard that you were not suppose to use synthetics on superchargers or turbos, but this was internet gossip, I never confirmed this tale....
TECH Regular
Joined: Dec 2006
Posts: 417
Likes: 1
From: Canada
well its an OFI kit. it gets hot here.. will burp past 100 some days but not to often. oil get chagned often
but i dont need to go syn desil do i? on a stock lt1 thats turbo charged. i should be fine with say some 10w30 as long as i change it often enought??
but i dont need to go syn desil do i? on a stock lt1 thats turbo charged. i should be fine with say some 10w30 as long as i change it often enought??
TECH Regular
Joined: Dec 2006
Posts: 417
Likes: 1
From: Canada
i dont plan on using syns in the motor till i get a new one. i have a feeling ill be the lucky one that switches over to syns and gets a hand full of new leaks
Than run regular 10-30 and change it often. If you need thicker than try something like a 10-40. I'm starting with a 10-30 for my stock 346, whether its sythetic or not.
its a well kept secret.
TECH Apprentice
Joined: Jan 2008
Posts: 366
Likes: 0
From: Gladstone, Queensland, Australia
Although I have had turbo cars, my SSV isnt turboed. It came from factory with 10W30 semi synthetic, I changed it with Shell Helix 5W40 full synthetic. Since I put the shell in it the motor valve train noise has increased with some lifter and valve train ticks.
15W40 is going in tomorrow. I believe if you drive your car hard at the strip and road sometimes a little higher viscousity is better.
It was proven in hot Australian conditions when Holden released the HSV with synthetic oil and the SS had the very same engines but used a thicker mineral oil. HSVs had high oil consumption, bearing failures and were generally noisy. Going back to a mineral oil solved the problems.
I have searched the forum and found many members valvetrain tick problems were solved with slightly heavier oils.
IMO I would run a 15W40 oil like rotella minimum and in a big hp forged engine I would even strongly consider a 20W50. The Mobil 20W50 is a very good oil.
I think where most people become confused is that the LS series engine is essentially still old tech. Its an alloy block with efi and roller lifters and thats it. But at heart it is still a large capacity OHV V8 which likes slightly heavier oils.
Manufacturers uses light weight synthetics to reduce friction and improve economy, although Multivalve small capacity 4s are using the same thin viscousities and yet they are largely different. I would suggest there is nothing wrong at all with higher viscousities
infact it is sensible to do so.
15W40 is going in tomorrow. I believe if you drive your car hard at the strip and road sometimes a little higher viscousity is better.
It was proven in hot Australian conditions when Holden released the HSV with synthetic oil and the SS had the very same engines but used a thicker mineral oil. HSVs had high oil consumption, bearing failures and were generally noisy. Going back to a mineral oil solved the problems.
I have searched the forum and found many members valvetrain tick problems were solved with slightly heavier oils.
IMO I would run a 15W40 oil like rotella minimum and in a big hp forged engine I would even strongly consider a 20W50. The Mobil 20W50 is a very good oil.
I think where most people become confused is that the LS series engine is essentially still old tech. Its an alloy block with efi and roller lifters and thats it. But at heart it is still a large capacity OHV V8 which likes slightly heavier oils.
Manufacturers uses light weight synthetics to reduce friction and improve economy, although Multivalve small capacity 4s are using the same thin viscousities and yet they are largely different. I would suggest there is nothing wrong at all with higher viscousities
infact it is sensible to do so.
