I use the Mobil 1 15W-50. I want a nice thick oil film protecting my bearings, but my setup is different from many of yours. I don't drive mine in the winter, always give it at least 5 minutes of warmup time before driving and never get on it until it's fully warm. For most people, it's the wrong oil. For a very high-po setup with loose bearing clearances it's great. Also, for a high mileage car where things have loosened up it might be a good choice for warm weather.

Rich Krause

 

ive been running 20-50 for over a year now, vavoline vr1 20-50. you guys suggest i change to something diffrent i do have 163k miles

 

I have one of the rare GM K.I.T cars..

No...really the motor felt allot stronger. Even smoothed out the idle some. No strange smells comming from the pipe just a calm running engine. You can really feel the difference when you switch to this oil. The funny thing is that when it's at the end of it's life line...like almost 4.5K miles...even though I change mine ever 3.3 it actually feels like the older rated oils. It's a more synthetic oil so it's good for any High-Pro engine. Highly reccomend. Would never use anything else ever! dumped it in my car at 35K been using it the last year or so, now have 20K miles on her and have been using nothing but the 15W 50. high Revs, Burnouts, doughnuts, Stages...The oil really does it's job well. No problems

I also mix it with prolong too....thats awsome as well.

 

How is it "more" synthetic than any other 100% synthetic?

New, from the makers of the Butt Dyno, the new Butt Engine Oil Analyzer!

 

You'd be much better off with a 5w30 or 0w30 if it's going to get below freezing a lot.

 

To be honest, none of them. The German made Castrol 0w30 is very similar to Amsoil though, and priced the same or less than Mobil 1.

But if you absolutely must use Mobil 1, go with their 0w40. Their 5w30 and 10w30 are simply too thin for the best engine protection, since they are both on the low end of the 30wt scale.

 

I use 20w50 all year round . We have a pretty moderate temp around here doesnt very often get below freezing here and I too baby my car till it warms up . All my cars , been using 20 50 in that ole 84 for years and nothing in the motor/valvetrain ever has given me any problems.

 

I am using 15w50 all yr round in NJ, b/c my LT1 with 60,000 miles leaks oil like a sive, i just got it i was going to be using 5w30M1 but i am sure that would all run out. So to try and slow the leak i am going to run the 15w-50 with bars stop leak.... If anyone can tell me where a good place to get these oil leaks fixed let me know, the whole engine is wet....it pisses me off but i have no money to fix it and i don't plan on working in that engine bay, it is tighter then my g/f

 

Bars stop leak is for your cooling system though! (unless they've started making an oil supplement)

Honestly though, no oil supplement is going to fix the leak if it's coming from the intake manifold. It needs to be taken off, cleaned thoroughly, and a new bead of RTV put down (preferably Permatex Ultra Copper)

If the leak is from another source other than the intake, this product can help slow down or eliminate many minor leaks:

www.auto-rx.com

I've used it myself and it does a real good job of cleaning your engine as well as fixing some leaks.

 

yes it is for the engine, not the cooling system.

 

on the M1 bottle is says it pours to -49 degrees, does anyone want to explain EXACTLY what that is, also where i live in the winter it usally is around 0 to 20 degrees F, do you think i will be okay with the 15-50 M1, what conventional oil has the same cold start thickness to it? I really want to look into this b/c of engine oul leaks everywhere and i can't spend money to have them fixed right now.

 

The Mobil1 website recommends 5w30 or 10w30 for the LT1/4 engines. Looking at the specs on their site, the 5w30, 10w30 and 15w50 are all very close:
pour point: -45 for all three
flash point: 224, 244, 230 (not sure why the 15w50 is a lower flash point than the 10w30)
Viscosity at 100: 10, 10, 17.4 (big difference on 15w50 here)
Anyway, I run 10w30 year round as we never drop below aroun 10 degrees, and I really don't see much difference spec wise between the 5w30 and 10w30 for low temp characteristics.

 

Different formula

 

I have a blown car that I only run from April to Nov. here in Ct. What would you guys suggest? I run Mobil1 5/30 now but want to switch to something alittle thicker. 0/40, 10/40, 15/50 I don't know any opinions please! Alittle light on this saga will be appreciated, thanks guys......John.

 

Iv used mobil 1 15-50 for about 3 yrs. now and I have no complaints about it.