I have 65,XXX miles on my LT1 and I'm thinking about switching to synthetic oil. What do you all recommend I should get? What weight? What about that purple brand? Any help would be greatly appreciated. Thanks!

 

I have been using mobile 1 for at least 15 years in my vehicles and no problems.

In fact you can see the mobile one label GM installed on my car when it was built in this pic!

 

I've ran amsoil in everything forever. No problems and it is 100% synthetic.

 

Mobil 1.
Its expensive, but my girl's worth it.

Give the motor some easy miles to adjust to the newer chemicals in the oil.
And make sure to change filter.

Synthetic and Straight DO NOT mix.
Once you go thetic, there's no goin back.

 

Mobile 1 Fully Synthetic 5W-30

 

ROYLE PURPLE all the way man its the most expensive but its also the best hands down

 

Wal Mart brand 2.88 a quart


Mobil1 is the good stuff IMO.

 

I also have to agree with the Royal Purple. I use it on everything- motor oil, gear lube, and tranny fluid. Heck if I can find it I'll even use the stuff they make for the radiator! It may be expensive, but I absolutley love it. I give the proper respect to Mobil 1 and Ams, but I wouldn't put either in my baby...

 

Do a single one of you have any MEASURED DATA to back up your recommendations? Judging from the recommendations made I would guess not.

You want REAL oil info not this "works for me" crap go too http://theoildrop.server101.com/ubb/ultimatebb.php the info you get from there will be 100 times better than from the boneheads here. People here want dyno and track info for mods but for oil they ASSume the marketting gimicks and GMs recommendations are the gospel.

 

Well Im a bonehead that runs Mobil1.... Have seen friends race cars running it without problems so that was good enough for my slow car......

But Caprice did put up a good site, that does have alot of good info.

 

Lets see Mobil 1 works just fine for most of the NHRA and NASCAR, if they are not using that then they use Royal Purple or AMS.

Do you simply believe everything you read ?

Yes it is a good site but I go with proven results, and if a big racing series trust the very product you put in your car well i will go with the pro's. And ask how I know, I happen to have friends in both industries so I am not just name dropping.

 

Believe it or not, I saw a UOA from Bobistheoilguy.com for the Supertech synthetic oil and it wasn't bad at all. I use it in my pickup. It's a group 3 oil with a decent additive package.

 

I never said M1 was bad. Those who actually research things though know there is more to this than weight or brand, while one brands 0w-30 is great in a motor another the 5w-40 may be a better chioce while the second brands 0w-30 blows.

If you think a 0w-30 is thinner than a 10w-30 then you don't know jak about oil and NEED to do some reading on that site.
The good news is as of late M1 has been thickening up a bit and the weights everyone MISTAKENLY thought were best for this motor are getting closer too right where before it was advisable to run a 40wt in M1 instead of the 30s.

 

The problem with a question like this is that opinions are like ********. Everyone has one. All of the oils listed are all excellent oils that are so similar that it is not worth noting. THe additive packages are a little different but thats about it. I run amsoil simply bc I get it at cost through the shop and it has an excellent track record. We run it it all of the patrol cars we service at the shop. If it works for the way the boys in blue drive and use them it is fine for me. We've never lost an engine due to high rpm lubrication issues in a patrol car. The amsoil package I run in mine in my 97 is 10w30 extended change with their full synthetic filter. 25,00 miles or one year and you don't have to touch it. Just add a little here and there. Which since I do not race my car has been just fine and it's as clean as a new penny inside. So long and short of it just do a little research and go with what you feel regardless it will be a good choice.

 

mobile 1. here.

 

are you serious you can go back and forth between synthetic and conventional oils as often as you want you can even mix them and run them like that. And another vote here for mobile one 5W-40 and ac delco or mobile one filter

 

i also heard that you can't mix the two. (not like i'm going to anyway). I'll probably just end up getting Mobile 1 because it's easily available.

 

Amsoil is good oil no doubt BUT it is VERY irrisponsible to suggest OCIs like that without UOAs to show the oil is not getting dirty or something. Amsoil bought a guy with a Toyota a new motor because it could not last that long in that motor and the engine blew. This was an engine Toyota built that ended up being VERY hard on all oils after they were in service even Toyota went back and lowered the OCI recommendation because it sludged up even quality oils so badly. Amsoil irresponsibly put that blanket 25K on there so they bit the bullet and paid for the engine, the guy should have verified how it worked in his application.


On oil you are right in that opinions are like....... BUT I am trying to offer people a way to look at measured data MEASURED not opinion.

 

http://www.royalpurple.com/techa/whyrpa.html here you go, this should help out some

 

This is what I am talking about that is MARKETTING if there is any truth to it it is purely accidental. Not that RP is necessarily bad or all that great. Go to the link I provided and see how it MEASURES up.