Perrin Engine Oil Cooler
 

Hey all,


Amateur BRZ owner/track enthusiast here. I recently had a shop install the Perrin Engine Oil Cooler and they mentioned it takes a bit more oil now but oil changes should be the same. My question is, does anybody know how much more oil it takes and is there anything about changing the oil that is different now? Just want to make sure I let any mechanics know about it before they do any oil changes.



Thanks,
Jason.

I know the EJ engine oil filters have a drain back valve and am 95% certain the FA oil filters do as well. What that means is you add the capacity of the lines and oil cooler core to the total capacity. Perring should be able to provide this info.

Another way of doing it, after you've added the normal full capacity, is start the car. Then turn it off. Check the oil The oil cooler and lines would now be full, and you can top off to the 'full' mark.

It’s approximately 1 extra quart of oil. Nothing really different about oil changes. The oil cooler will retain oil between changes so no need to add extra oil. Follow Perrins instructions after installation (prime the engine to make sure oil is pumped through the cooler before starting the engine).

You guys don't drain the oil cooler? 1 quart is a lot to just leave in there.

Any OEM car I've owned with a remote oil cooler includes draining the oil cooler as part of the oil change procedure.

Odd. I’ve never been instructed through literature or otherwise to drain my coolers on my other cars. Most held at least a liter in the cooler, some two plus. Was not deemed material to the overall capacity, though I’d disagree on my RX8s that would only drain about 50-60% of their capacity in a single oil change.

I don’t, but I also had short OCI’s, roughly 3000-3500 miles. I’m not sure there would be an easy way to drain the oil in the OC, nor was it recommended by the manufacturer. I did a UOA and it looked fine even with heavy canyon use and a few track days.

Nope. Always heard not to bother. 7500mi on oil changes(0-20 300V) with as many as 6 tracks days and UOA’s always look fine.

Off. My C63 and GT500 both have the oil cooler drain as part of the procedure. My 2016 Police Interceptor (winter beater) just says to get the oil to operating temperature so the oil cooler can drain with the engine oil.

Makes me wonder if it depends on the location, Both AMG and Shelby have them in the lower grill.

With the filter up high on the BRZ, I'd expect it to hold all that oil. With EJs we'd just add an inline Tee and Ball Valve Drain so you could dump the oil cooler lines and heat exchanger easily. I'd still do that on the BRZ. It's only ~$20 and I'd rather not have ~20% of the old oil still in there.

Interesting. I always thought it was a little odd to leave the used oil in the heat exchanger. I like this idea in theory. What are the real-world downsides?
1. cost (negligible)
2. more points of potential failure (not a huge concern if done right)
3. what else?
Why wouldn't someone do this? Is 20% old oil just not enough to have a real-world negative impact? I could see that argument, but it kind of just seems lazy to me at the same time. It's not like one intentionally leaves 20% old oil in when there isn't an aftermarket oil cooler added.

For me, the bolded part above was my reason. As long as my UOAs were coming out clean, why bother? It's expending resources to solve a problem that doesn't exist.

I Like the idea of draining the oil cooler but access is not feasible where I mounted mine. It is behind the AVO intercooler but in front of the radiator. I change the oil regularly anyway so the oil that is in the cooler is in good shape anyway. Every 3k miles, or After any 3 track days, or will not do a track day with more than 1k miles on the oil.

For those who want to drain the cooler the best way to do it is mount the cooler were one side is low, us a AN T and but a B nut cap on one side. If you are worried about the B nut then you can drill it and safety it.

For now. I'd rather not see how that plays out over time. By your premise, you might as well go beyond recommended OCIs, or only change out 3 quarts, to save resources. If this were an LS engine or any other engine on the planet that had better rod bearing oiling, the risk would be pretty low, but we're talking about a Subaru engine that already has known lackluster rod oiling from the factory.

There's always about 1/2 quart in the engine at an oil change (with or without a cooler). Adding another quart or spent oil to that, at some point, I can't imagine that would be good over the long term as part of that oil is always going to be from previous change, and the change before that, and so on.

Interested to see how your UOAs look over time.

I’ve since switched to a 2nd gen BRZ, but FWIW, I did around 35k miles, 30 track days, 80-100 canyon drives and ran an e85 tune after adding the oil cooler and everything was fine when I did a UOA at the tail end. As long as the UOAs are coming out clean (TBN is good, oil is testing within graded viscosity, and there are no excess wear metals), I don’t see how it could be a problem. This is just my opinion though, not trying to convince anyone to adopt my approach. Everyone should feel free to get their own UOAs and change out the oil in their coolers if that makes them more comfortable, it makes no difference to me 👍

Also just to be clear I’m not recommending anyone go past their recommended OCI, in fact as I stated earlier I was changing my oil at less than half the OEM recommended OCI, partly due to my usage case and partly from knowledge that the oil cooler was retaining some old oil. Ultimately I think a UOA is the only reliable way to judge remaining oil life, and absent that, then following the OEM recommendation is a good approach.