I bought this Si used on Labor Day 2017, and this run of 0W-40 is the first change of oil I've personally put through it. I chose to stick with the recommended interval of the onboard maintenance minder as a baseline for my first analysis. The car's driveline is entirely stock, but I did replace the air filter with an OEM Honda filter at the start of this oil change. The oil filter used was also an OEM Honda A01 unit.
This car is spec'd for 5W-30, but given my aggressive driving habits, hot climate (east GA), and a positive Civic Si OW-40 UOA from user JoeFromPA, I felt the added thickness, good $$ value and stout TBN of this oil as essentially a "beefy 30 weight" would be the right call.
Additionally, Honda's higher performance Japanese-market Type-R variant of this chassis, the "FD2", calls for a 5W-40 weight in the factory service manual. Given that the engine in that car is essentially identical internally to mine, aside from a slightly hotter cam and the deletion of balance shafts in the sump, supported my thought that the engine would be happy with a 40 weight oil.
As you can imagine, I'm quite pleased. It looks like the 0W-40 dipped down right into that middle/high 30 weight range at the end. I take care to drive the car gently until its fully warm, but otherwise it sees normal shifts in the 4-5k RPM range and sees the 8,200 RPM redline multiple times a trip, as it should. I bought the car as a practical daily driver, so it sees all the rigors of traffic, long interstate trips, extended idling with the A/C cranked up, and lots of engine shutdowns/cranks when running errands.
Given the results I don't feel inclined to change viscosities. I got a great deal on Pennzoil Euro 0W-40 from wally world so that is currently in the sump with another A01 oil filter. My plan is to take that oil out to 8-9k miles and see what the UOA turns up. I have a feeling I'll settle in somewhere around 10k mile change intervals by the time I find the sweet spot with these 0W-40s.
Comments welcome. Thanks!
This car is spec'd for 5W-30, but given my aggressive driving habits, hot climate (east GA), and a positive Civic Si OW-40 UOA from user JoeFromPA, I felt the added thickness, good $$ value and stout TBN of this oil as essentially a "beefy 30 weight" would be the right call.
Additionally, Honda's higher performance Japanese-market Type-R variant of this chassis, the "FD2", calls for a 5W-40 weight in the factory service manual. Given that the engine in that car is essentially identical internally to mine, aside from a slightly hotter cam and the deletion of balance shafts in the sump, supported my thought that the engine would be happy with a 40 weight oil.
As you can imagine, I'm quite pleased. It looks like the 0W-40 dipped down right into that middle/high 30 weight range at the end. I take care to drive the car gently until its fully warm, but otherwise it sees normal shifts in the 4-5k RPM range and sees the 8,200 RPM redline multiple times a trip, as it should. I bought the car as a practical daily driver, so it sees all the rigors of traffic, long interstate trips, extended idling with the A/C cranked up, and lots of engine shutdowns/cranks when running errands.
Given the results I don't feel inclined to change viscosities. I got a great deal on Pennzoil Euro 0W-40 from wally world so that is currently in the sump with another A01 oil filter. My plan is to take that oil out to 8-9k miles and see what the UOA turns up. I have a feeling I'll settle in somewhere around 10k mile change intervals by the time I find the sweet spot with these 0W-40s.
Comments welcome. Thanks!
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