GTX 5w-20; 6k-7k miles; 2007 Civic (2 cars 3 UOAs)

[JimBlake]

Two 2007 Honda Civic Coupes, both with the R18A1 engine & manual trans.
Oil type: Castrol GTX 5w-20 (both cars).
Blackstone UOA (all 3 times).

These are my 2 daughters' cars and I wanted to know whether I should trust the oil-life monitors.

Code:


2007 Civic Coupe LX

Castrol GTX 5w-20

OLM reading: 10.%

miles (oil): 6,153

miles (car): 17,615

date: Sep-2008



Aluminum: 10

Chromium: 0

Iron: 11

Copper: 2

Lead: 0

Tin: 0

Molybdenum: 74

Nickel: 0

Manganese: 1

Silver: 0

Titanium: 0

Potassium: 3

Boron: 12

Silicon: 20

Sodium: 181

Calcium: 1657

Magnesium: 6

Phosphorus: 649

Zinc: 819

Barium: 0



SUS visc.210F: 51.8

cST visc.100C: 7.83

Flashpoint F: 385

Fuel: < 0.5%

Antifreeze: 0.0%

Water: 0.0%

Insoluables: 0.3%

TBN: 3.0


The above Civic LX gets less miles vs the other car. Having the TBN of 3 gave me initial confidence in Honda's OLM (at least for GTX). Guess I was lazy & didn't post that UOA when I had it done (or maybe I just don't know how to search the forum).

The below Civic EX gets more miles per year, driven more often but not vastly longer trips. I guess I'd call em both "rural/suburban" because they're for commuting to school & work, but not "big-city" type downtown driving.

Code:


2007 Civic Coupe EX

Castrol GTX 5w-20

OLM reading: 10.% -104miles

miles (oil): 6,322 7,274

miles (car): 85,363 105,172

date: 13-Aug-2011 30-Sep-2012



Aluminum: 8 7

Chromium: 0 0

Iron: 6 6

Copper: 1 1

Lead: 0 0

Tin: 2 0

Molybdenum: 55 1

Nickel: 0 0

Manganese: 0 0

Silver: 0 0

Titanium: 0 0

Potassium: 0 2

Boron: 12 2

Silicon: 16 15

Sodium: 178 234

Calcium: 1817 2044

Magnesium: 9 4

Phosphorus: 624 684

Zinc: 659 797

Barium: 0 0



SUS visc.210F: 54.4 53.3

cST visc.100C: 8.6 8.28

Flashpoint F: 365 375

Fuel: < 0.5% < 0.5%

Antifreeze: 0.0% 0.0%

Water: 0.0% 0.0%

Insoluables: 0.5% 0.4%

TBN: -- 2.0


The 2011 oil sample was just for the purpose of getting a feeling for the general health of the engine. I didn't get TBN at that time.

The 2012 oil sample was after we let the OLM get all the way down to zero, then another 104 miles. I wanted to know if I went far enough to hurt anything. Blackstone suggested I could've gone to maybe 9k miles.

For me, this tells me that the OLM is a bit conservative when using Castrol GTX. In the past I've been skeptical about the long oil changes that cars are calling for these days. Between these 2 Civics I'm inclined to trust Honda's OLM and even allow it to go down to zero. (The maintenance reqd. lamp comes on at 15%)

 

[Hermann]

Look good to me. Silicon a bit high on both. I would check ductwork on the air filters and use OEM filter if you are using non OEM disposable.

 

[ARCOgraphite]

Looks good for MT. Was the 2011 report using API-SM and the 12 using API-SN? I see a formula change here.

 

[Lead Shoes]

They look to be wearing in well, nice job on getting them a real car (manual). It really stops her from borrowing out the cars to friends because not many young people can drive a manual anymore.... and texting while driving? Not likely, same with talking on the phone while driving around any urban area.


Here's to secret parenting

.

 

[JimBlake]

I can't edit my posts, huh? Forgot to mention those were all with Pure-One oil filters.

Unfortunately, I didn't record SL/SM/etc when I put any of this oil INTO the cars. Agree about the formula change. I generally buy oil when a deal comes up. Sometimes when I change oil, I end up with the last bottle of a batch together with bottles from the next batch.

For the first car with 17k miles; Blackstone suggested Si comes from engine-assembly sealants. That one still had the factory air filter. I use disposable air filters, usually Purolator. Didn't buy them from the dealer, but they still seem to have the same thick felt-like material same as the original "Honda" filter. Ductwork is clean (I do check that).

funny OT about the transmissions:
Inherited an AT Accord just before younger kid learned to drive. She wanted the auto, I said OK, but made her learn clutch anyway. She ended up hating the auto & she wanted MY car instead. Some guy came around to impress her with a new/old car he just got. All she could do was laugh at him for not knowing how to drive manual.

 

[addyguy]

I like that GTX has started to use moly in its oils....minor point, but I like to see it.

GTX has always been a stout oil, able to easily do 6-7k OCI's.