Did we ruin our engine? This is what an oil analysis test revealed

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Tom
Update by Tom Suddard to the Porsche Cayman project car
Aug 8, 2023 | Porsche, Oil, Cayman, Porsche Cayman, Engine Oil, Oil Analysis, LN Engineering, Driven Racing Oil, SPEEDiagnostix

Whelp, we did it: My wife and I bought a broken Cayman in Seattle, Washington, and then drove it all the way home to Florida in fourth gear. Washington, Oregon, Idaho, Nevada, Utah, Colorado, Arizona, New Mexico, Texas, Louisiana, Mississippi, Alabama and Florida: As we learned, these are all states that can be driven across in a Porsche screaming at 4100 rpm.

(If you’re interested in the finer details of our trip, you can follow along in the live thread we kept while we were on the road.)

Now that the car is home, I found myself interested in a much more expensive detail: Had we ruined the car driving it that far without the top two gears?

Particularly, I was worried about the health of the engine. I’ll be honest here: Modern cars are amazing, and I had little doubt that a used Porsche could scream across the country without exploding. But I was still curious, and lots of people on the internet told me it would surely blow up. So it’s time to find out what really happened inside the Cayman’s engine, and an easy way to do that is oil analysis.

Before we left Seattle I mailed a sample of the Cayman’s old mystery oil off to SPEEDiagnostix, an oil analysis company recommended by our Porsche friends at LN Engineering (and included a kit in their generous care package for this trip).

For $69.95, SPEEDiagnostix will analyze your oil sample and tell you everything there is to know about it, including how well the oil is working, what pieces of your engine are floating around in it, and what you might change to get a better result next time.

After draining the mystery oil, I poured in a fresh fill of Driven Racing Oil DI40. Why this oil? It was also in our care package from LN Engineering, but came well-reviewed from the oil analysis folks, too.

Those initial results came back while we were halfway through our trip. Viscosity was slightly below grade, which they noted was typical for Mobil 1, as was the measured additive package and oxidation value. But “all other results are within normal ranges.” So I had our baseline: When the Porsche left Seattle, it had a perfectly good engine with no issues.

But what about after more than 4000 miles at 4100 rpm? I took a fresh sample, packaged it up in the prepaid SPEEDiagnostix box, and paced back and forth across the shop for a few days while I waited for the results. That little bottle would either prove I’d made a $15,000 mistake or prove that you really don’t need 5th and 6th gear to drive across America.

Then the email came. The results didn’t just show healthy oil. It showed healthier oil than the first sample, with “fantastic” single-digit numbers on all wear metals. In short, my Cayman shrugged off the abuse with a smile on its face, even if it was screaming the whole time.

So we didn’t blow it up.

What’s next for the Porsche?

Well, it’s time to stop procrastinating and pull that broken transmission out. We’ll do that in the next installment.

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Comments
bobzilla
bobzilla MegaDork
8/8/23 9:01 a.m.

You know you have your own Oil Analysis guy here..... Just sayin'. 

BA5
BA5 GRM+ Memberand HalfDork
8/8/23 10:05 a.m.

One of the longevity tests manufacturers do is to just run the engines at redline and full load for weeks on end. I think it'll be ok.

bobzilla
bobzilla MegaDork
8/8/23 10:41 a.m.

Why this oil? It was also in our care package from LN Engineering, but came well-reviewed from the oil analysis folks, too.

I mean, the founder of the lab is also the developer of the oil so I would be shocked if they were critical of it. 

Tom Suddard
Tom Suddard GRM+ Memberand Director of Marketing & Digital Assets
8/8/23 10:59 a.m.

Bob, I didn't realize you were an oil analyst. What do you think of the results? And was I correct in going into this with the assumption that this would be no big deal, anyway?

 

bobzilla
bobzilla MegaDork
8/8/23 11:20 a.m.

In reply to Tom Suddard :

There report is a bit hard for me to read. Not sure why they add all the wear metals together. Kinda odd but maybe that's their thing. I do know they use a different method for their elementals. It's an older out dated method that's being bright back with new technology and equipment. 
 

as for the results themselves the appear normal. There is always wear in an engine. It's the amount you need to watch. Keep in mind sampling procedures (how you obtained the sample) can have the largest effect on results. There's a lot of variables in play. That sample wouldn't concern me. If you were truly worried I'd continue to sample to monitor the trend to make sure it's fine. But barring any known issue I wouldn't be worried about running an engine for extended time at higher rpms. 
 

edit: although I think maybe I should raise my prices if they are charging $70 per sample

t321sg
t321sg New Reader
8/8/23 1:22 p.m.

You said it was mystery oil that you drove across country - but the initial analysis referred to Mobil 1. So does the lab believe it was Mobil 1 in the engine when you bought it and drove it across country?

j_tso
j_tso Dork
8/8/23 1:24 p.m.
bobzilla said:

You know you have your own Oil Analysis guy here..... Just sayin'. 

Bob is the oil guy...?

bobzilla
bobzilla MegaDork
8/8/23 1:26 p.m.

In reply to t321sg :

There's no real way for the lab to answer that question. Additives can be similar but be sold as different oils using a different base stock. The way its supposed to work is you work from the information on what the oil is supposed to be. When you start looking at the sheer volume of oils out there trying to work backwards is just not something you can do reliably nor cheaply. 

bobzilla
bobzilla MegaDork
8/8/23 1:27 p.m.
j_tso said:
bobzilla said:

You know you have your own Oil Analysis guy here..... Just sayin'. 

Bob is the oil guy...?

Not that guy, but kinda

 

Tom Suddard
Tom Suddard GRM+ Memberand Director of Marketing & Digital Assets
8/8/23 1:29 p.m.
t321sg said:

You said it was mystery oil that you drove across country - but the initial analysis referred to Mobil 1. So does the lab believe it was Mobil 1 in the engine when you bought it and drove it across country?

We drained mystery oil out of the car before driving cross-country, then drove across country on the Driven DI40.

Bob's correct--there's no easy way to tell what was in the car when we purchased it. But given the dealer service history and the lab's observations, we suspect it was Mobil 1

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