Anybody ever try the Mobil 1 full synthetic 0W40 in there car? If so any pro's or con's. I know it's a european car formula, but when you can get it for free why not use it. Thanks.

 

I've seen a few oil analysis of M1's 0W40 and they all seem to be good. From what I've seen on most LS1 reports, they could best use a 30W on the thick side or a light 40W.

I've used 0W30 since the car was new untill around 30K miles then changed to 0W40. I just did a cam swap and the interior of the motor was spotless, timming chain looked new.

On my last oil change, I went to Castrol German 0W30 because of the excellent results I seen. It's sometimes hard to find and since you can get the 0W40 for free,,,, then I would be useing the 0w40.

 

Mobil 1 0w40 is the best viscosity to choose from out of the Mobil 1 lineup. Much better than their 5w30 or 10w30. Go for it!

 

castrol 10w30?

 

I switched from mobil1 5w30 to mobil 1 0w40 and i have noticed less consumtion and higher oil pressure

 

Is not that great, their 0w30 (from Germany) is much better, it's thicker at operating temp and thinner on a cold start. So it's the best of both worlds. And it doesn't thin out as the oil gets older, in fact it thickens slightly. Mine ended up thickening up into a 0w40 at the end of the last 6200 mile interval I did with this oil.

 

How many miles do you run betweem oil changes?

 

So Mobil1 0W40 syn is better than the 10W30 syn?

 

Amsoil 10W-40 is what I am using right now, but I think I am going to try The Mobil1 0W-40. The Amsoil is good, but it seems to be on the thin side compared to other 10W-40 weight oils.

 

I've been using Mobil 1 0W40 Full Synthetic for my last three oil changes? Before that, I used Mobil 1 10W30. I got the car with 27K on the odometer. I'm not sure what the previous owner used, but when I took the car apart this weekend. The inside is pretty damn clean. Not alot of gunk like I used to have in my old Firebird.

Mobil 1 0W40 for now, but after the heads and cam. I think that I'm gonna switch over to Amsoil 5W30.

 

I go 10,000km (6200mi) on my Firebird, 8,000km (5k) on my wife's car (she does shorter trips)

 

Without a doubt.

 

Amsoil 5W-30 is thin stuff! You won't have the oil pressure that you have now! I bought my Z last year with 92,000 miles on it! I have always used Mobil1 in all my other vehicles, but Mobil1 did not offer a 40W oil which I thought I should use with that many miles. So I tried Syntec 10W-40. Then I switched to Amsoil 10W-40 and my oil pressure dropped about 10psi overall. It wasn't bad, just less than the Syntec, but more that the 5W-30 that was in it!

I am doing a head and cam install also, but I am not sure what I am going to do afterwards! I know that Mobil1 and Amsoil are the top 2 oils based on an independent study! It will be a 40W either way!

The only thing that should make a difference in a high mileage vehicle is ring wear and seals! I don't think the bearing clearances would have changed much if at all, but where I live it is hot most of the time, so a 40 weight oil usually works better! I have used Mobil1 15W-50 in all my other high performace cars, but I know that LS1s have thighter clearances than the engines I have built in the past.

 

Amsoil 5w30 is not thin at all, in fact it's a thicker 30wt oil which is almost a 5w40 to begin with and it tends to thicken up as you put more miles on it.

Mobil 1 0w40 is a very good oil and he would have higher oil pressure to begin with, but this oil also has a tendancy to thin out slightly, so if you ran Amsoil 5w30 for 6000 miles, and Mobil 1 0w40 for 6000 miles, both of them would most likely end up at the same viscosity at 100c (around 12.5 to 13cst)

 

Patman,

What are your thought on the M1 15W-50? I find it interesting that the label says its for high performance, blowers and comes standard in the Cobra R. That Cobra R motor isn't anymore special than an LS1 that would warrant a special oil except for the intended use of the car.

 

I honestly think that 15w50 is simply too thick for the LS1, especially one that sees regular street duty. These engines simply do not need an oil that thick, not many engines out there do in fact.

 

Patman, I notice you seem to be the oil guru guy. Why dont you use the schaeffers oil? from what you have seen on bobistheoilguy site I thought you would have given it a try by now.

 

I have tried it actually, I ran it in my car for a year, and found the lead numbers to be higher than I liked. Switching to German Castrol 0w30 dropped my lead wear (bearings) by a large amount. It is a very good oil, it just didn't match up well in the LT1, at least not their 5w30 and 10w30. I should've run their 15w40 in the summer, I've seen it perform well in an LT1. But I also prefer to run the same oil year round, so that 15w40 wouldn't have worked well here in the winter.

 

I change my oil every 3000 - 3500 miles.

 

What I meant was it looks thin out of the bottle! The 10W-40 looks thin out of the bottle also, but what I was saying is that he won't have the oil pressure with a 40w compaired to a 30w. As I stated above, I have used alot of different oils. Some of the same wait run higher oil pressure than others. I believe in Amsoil! I use it!