Title says it all.
Two days ago, I was driving home, and heard a weird sound.
“That’s definitely knocking,”
But it wasn’t constant; it only happened when I let my foot out of the accelerator.
Piston slap.
“Huh. That’s odd. When was the last time I checked the oil?”
For context, my car, a heavily-modified 2013 Subaru WRX with (mostly) stock internals, is well-known for being an oil-consuming pain-in-the-ass.
At the time that I could do it, I spent tens of thousands of dollars installing reliability mods. I did so over the course of several years, adding an air-oil separator, a KillerB oil-delivery package (pickup, baffle, and pan), and so many more that one day I’ll figure out and put together here.
The goal was/is to first so dramatically overbuild the reliability mods, to make the car functionally rock-solid.
I’ll then add the 6-Speed ($4-5K), a giant brake package ($4-5K), wheels and tires ($5-6K), and then as much as I can/want on a massive 500+ horsepower/500(ish) foot-pounds torque engine ($10-20K) with a singular goal:
I want to be able to do a sitting 4-wheel burn-out at will with Michelin Cup 2s.
Life goals.
So as a part of that over-building reliability journey was researching fluids – oil, coolant, brake/clutch fluid, & gear oil.
Coolant – using the Subaru OEM.
Or at least, that’s what I’m supposed to say. What’d I’d say if we were standing there talking is that I use ‘Asian Vehicle Coolant Blue’ from Zerex, for the last three years.
In some circles, that’s heresy.
But I digress.
I flush my brake fluid once a year, with DOT-3. Brakes are happy.
Gear oil is Subaru OEM, and this time I’m not being facetious. There are other combinations that allegedly work better, but given I won’t dump the clutch because the OEM 5-Speed in Subarus are a split-case house of cards waiting to shatter under high-torque scenarios, I don’t do much but simply change the gear oil on-schedule.
I tell you all of this, not burying the lede, but to establish my credibility for what comes next:
The oil – a subject of much discussion, bro-science, and much misinformation. I spent about a year and many dollar bills submitting my different oil samples to Blackstone Oil Testing, and when I got great results from a particular oil, where I had less materials in the oil than any of the other samples, for me, it was clear:
Yes. I’m totally a filthy Brotella shill.
I’m also a heretic in some circles for something else I did that I believe saved my ass: I’m an oil-additive acolyte, totally from an experimental point of view.
So long as it can’t hurt, I’m happy to add something that *might* save my ass.
In my opinion, based on what I’m about to share, I believe it did.
Now, let me address something here quickly – some of the additives out there *can absolutely destroy your engine* from the acidic by-products generated by the break-down of the additives, including the one I have, and after this, will again, use.
At one point last year, I did some homework on additives. There’s a common refrain amongst the faithless: if these additives were so great, they’d be included in regular oil.
And I agree, but here’s the rub: when used with thought and consideration, I think you can benefit greatly – which, again, I think I did – so let’s get into it.
I will trust Motorkote for the rest of my life.
Anyone who knows anything and is skeptical about additives is potentially face-palming right now, and for good reason: quoting directly from one of the most trusted oil-studying websites on the planet – Motorkote is 27% chlorinated paraffin, which is well-known for destroying engines. It’s engine cancer in a bottle.
Can’t disagree.
HOWEVER!
I had questions. So I read. A lot. I watched a lot of videos on the topic of chlorinated parrafins and specifically Motorkote.
I can’t recreate my steps on how I got to this conclusion, but here’s what I came to decide with my vehicles – I use it as a treatment versus constantly having it in the oil. I ended up deciding to do so every 5 or so oil changes; basically deciding to add it once a year at the same time I do my brake fluid and transmission/diff gear oil.
I put Motokote into my vehicle about 500-1000 miles before my next oil change. I used the prescribed amount per the bottle. I did the oil change. I then added fresh oil, and added Motorkote again, filling the difference.
Then I changed the oil again at 1,000 miles, removing the Rotella/Motokote mixture for regular Rotella.
Yeah, it’s expensive.
I get it.
But here’s the operating theory I came up with – the chlorinated parafin only becomes corrosive when it breaks down from heat cycles. In the meantime, it bonds to the metal in the engine in the same process, with the oil as the delivery method. I add the Motokote to the old oil to help it clean sludge and other contaminants.
This is disputed, and I get that.
But then I pull the oil and filter, add fresh, and put a larger percentage of Motokote in on the fresh refill.
Running it for only 500-1000 miles (I can’t find my notes, so I’m splitting the baby), I get the benefit of the bonding, but don’t leave the corrosive by-products floating in the oil for a long period of time.
I also did the same thing in my differential and my transmission, with continued success.
To be clear: this is absolutely bro-science, because I can’t easily tear down my engine to analyze my process. Any claims to the alternative would be disingenuous.
However, I can absolutely speak to the extra MPG I got immediately afterward, adding 2-3MPG.
Not significant at a micro scale.
At macro scale, over the 60K+ miles I’ve put on the car since? The savings are immense, even with the $100-$150 extra I spent on additive and extra oil/oil filter.
I also believe it saved me.
Here’s the story you came for:
Subaru WRXs are notorious for spinning bearings, as mentioned above. I was concerned about the aforementioned when I was hearing what founded like piston slap/a spun bearing.
I finished my drive home, parking the car and hearing clattering as I shut the engine off.
I was very concerned.
Next day, I check the dipstick.
Oil didn’t even register.
Well, shit.
Found a half-used 5-quart bottle of Rotella and poured roughly 2.5 quarts into the engine.
Checked the dipstick.
Still not registering.
Now, understand that the KillerB oil pan is deeper, so it takes more oil to register on the dipstick. Something to know for this story: the engine goes from having 4.4 quarts of oil to a little under 7 quarts total.
I’m a little concerned that the 2.5Q didn’t top it up. I find another half-used 5Q bottle… and empty it in.
And it finally registers on the dipstick.
The very end of it.
Which tells me I’m still 2 quarts low.
So, I fire up the car, run to the store, and add the last two quarts.
If you’re keeping score, I added somewhere between 6.5 to 7+ quarts.
I start up the car, and Ru sounds like she’s suposed to sound. No clatter, no slapping sounds on deceleration.
I’m so very embarrassed and yet so very relieved.
I share this story only to share the experience and hope that maybe someone else can benefit from my negligence and experience with chlorinated paraffin additives.
I don’t know that my results are specifically from this, but I have a hard time believing it had not.
I’d love to hear comments about this. Hopefully someone sees this and has something to say about it.
