BadCon

I figured I'd post this in this forum as it seemed most applicable to those of us with superchargers. I know recent conversations have occurred regarding what oil weight to run with a supercharged 5.0, so I took the time to send off my latest oil change for analysis at Blackstone Labs..

This run consists of 5w-30 Amsoil SS + 10oz of Liqui-Moly MOS2 (additive). The interval was for approximately 5 months through spring and summer, for 4000 miles. During this interval there was a dyno tuning session, lots of over the road tuning, and numerous simulated 1/4 mile runs and aggressive driving through Texas heat. I sent off the sample as I suspected I might have a leaking fuel injector due to some vapor lock issues I was having after the car had sat in the heat for a period of time, and I was curious if there was any fuel dilution. The results showed no fuel dilution and acceptable levels of wear. I've posted this information at Bobistheoilguy.com should anyone be curious to read their comments in the used oil analysis section. During this run I ran a couple cycles of fuel injector cleaner and a round of Royal Purple octane booster.

I refilled the crankcase with more Amsoil SS 5w-30 and about 5oz MOS2, but after this interval which will be short, I'll be switching to an oil with a higher HTHS, likely the new Mobil 1 ESP 0w-40 or even Redline 5w-30, depending on whether the new Mobil 1 ESP 0w-40 is finally available locally. That said, I'm not super concerned about the 5w-30 SS as it survived a Texas summer with me behind the wheel and we are approaching winter and the temperatures will drop.

engineermike

dunerinaz

What's causing the high magnesium numbers? That wasn't mentioned in the summary.

engineermike

BadCon

This run was only 4000 miles, so TBN would have still been relatively high, which is why I didn't pay for it. I'm not planning on extended oil changes with this truck, I don't drive enough and it gets boring changing the oil only once a year.

Most oils now are exchanging some of the calcium for magnesium in the additive package, this has to do with the new formulations developed to combat low speed pre-ignition, or LSPI. No really a concern to use 5.0 guys, but since many cars use smaller turbocharged engines, the new oil specs like SN+ and Dexos 2 (GM spec), are requiring formula alterations. Oddly enough Magnesium was used in old school oils in place of calcium, its funny how things come full circle.

BadCon

Thought I'd update this with my latest analysis. This run was also with Amsoil SS 5w-30, and was run over the winter for about 6,000 miles. This run had the same filter as the last run, I never changed the filter after the first analysis. I put in about half a can of Liqui-Moly MOS2, which was less then the first run. There were no track runs on this sample, but a good number of street runs with my Dragy and some data logging. Otherwise just normal driving. There was one incident where I started the truck after an injector swap with the old tune, and it ran super rich idling for a few minutes, but fuel dilution didn't seem to be an issue. Flashpoint is down, but there are various factors that could effect that and wear numbers were still good.
I've since switched to Mobil 1 0w-40, so we will see if an increase in viscosity helps wear numbers.

Ecks

Interesting.. I just got a case of Amazon's 5w30 Full Synth to try out on my next oil change.
Used Motorcraft on my last two. Would be interesting to see how Amazon's stacks up (especially being so affordable).

robbieg

Thanks for updating. Please post up the 0W-40 numbers once you get them. That’s the oil I’m considering running on my next change but still on the fence.

rojizostang

Well I was happy not knowing lol. Something else to worry about now. Thanks Chad.

malloy

I'm a Master tech at a Mercedes-Benz dealer. ALL of our vehicle's produced after 1997 receive mobil 1 5w-40. this oil is used from the $30k CLA to the $200k AMG's only the McLaren/MB SLR calls for a different oil and that is mobile 1 5w-50. I run the 5w-40 mobil 1 in my truck.