Castrol GTX 10w-40, 4339 miles, MY05 Subaru Forester XT
- Thread starter Tanj
- Start date
- Status
Man, the remaining factory fill that dilluted this run of GTX bumbed the moly up over 300%!
Well, it looks like everything is headed in the right direction. That's some serious moly in the factory fill
I think she's shedding Moly.
I think she's shedding, Moly.
OK OK - maybe some of the organoMo coating wears off......
I think she's shedding, Moly.
OK OK - maybe some of the organoMo coating wears off......
I just got a quick question....we've seen changing the factory fill for synthetic or boutique oils, etc., but......you changed the factory fill at 1k mi. to put in what?? Castrol GTX? What for? Couldn't wait to put in wal-mart available oil to replace what the engineers at the factory thought were the best for the car a week after you bought it???
Sorry for the rant...I was just wondering....
Sorry for the rant...I was just wondering....
Please do no not ever run Castrol 10W40 GTX in this car ever again!! Please!!!! Better choices for this car in a 40Wt. would be Chevron Supreme, Havoline, Mobil Clean 7500,Mobil-1 EP 10W40, Mobil TSUV,Rotella-T Synthetic, Valvoline Maxlife Synthetic 10W40,M1 OW40 even Castrol Syntec 10W40. Castrol GTX is cruel and unusal punishment for this engine!!
On a serious note GTX is well known to cause varnish issues in a number of import engines. I have seen it in older Toyota's and Pablo has seen it in Volvo's!
On a serious note GTX is well known to cause varnish issues in a number of import engines. I have seen it in older Toyota's and Pablo has seen it in Volvo's!
Yup, Pennzoil causes sludge too
GTX is a fine oil. I can't see how Chevron/Havoline in 10w-40 would provide any better protection. I believe this gentleman has posted that he's just running the dinos till around 10,000 miles, when he plans to switch er over to synthetic.
Since everyone seems to think I’m a nutter here are a few things to put my decisions in perspective. Subaru says the factory fill should be changed at 3k with 1k of that as break-in. While it looks like Subaru may use some special oil (it may be a special oil with lots of Moly in it or it could be plain jane Japanese oil that becomes saturated with Moly from engine parts during manufacturing) Subaru says that the oil can be changed at 1k. Upon analysis of the factory fill at 1k it was found to have thinned out to a 20 weight. As far as I'm concerned that would be plenty of reason to change the oil in a 4cyl turbo that has a factory recommendation of 5w-30 and that I intend to run pretty hard. I also wanted to get the miscellaneous casting/build crap out of the oil at the earliest possibility.
As to my selection of new oil I'm stuck with a slight quandary. Here in Texas driving a 4cyl turbo spiritedly with full intention of track days I seriously don't consider a 30 weight oil as up to snuff. However choosing a 40 weight or 50 weight becomes difficult as I try to meet the necessary oil requirements for Subaru's warranty (primarily API-SL and GF-3). As John Browning has indicated there is a host of very capable oils out there but meeting these two specs thins the field down significantly. I also have no desire to pay a significant premium for synthetic oil that I have zero intention of running an extended drain period on due to my driving patterns. While this vehicle will not necessarily be my daily driver I expect it to see some 30% to 40% of my daily driving taken in this vehicle. And at a round trip of 5 miles to and from work I easily fall into what is considered harsh driving environment by Subaru with recommended drain intervals of 3.7k. And when the vehicle isn't being driven as a semi-daily driver or the occasional highway diversion it will be run hard at track days and club drives. So when I went out looking for replacement oil I wanted a dino oil that was readily available from local stores. As it turns out the only 40 weight dino oil to meet both of the Subaru warranty concerns was the Castrol GTX.
As to the concerns of varnish with Castrol GTX I’ll take that into consideration. We must note however that this is a new API-SM/GF-4 formulation that may very well behave quite differently then prior oils. BITOG has the nasty habit of writing off something as bad only to never revisit the subject again due to “legends” despite changes having taken place. I plan to continue running UOAs for the entire time I own this vehicle so if any signs of varnish or sludge begin to appear I won’t be taken unawares. Also the 2.0L and 2.5L Subaru engines have so far had an excellent wear record even up into the 150k+ territory. It may very well turn out that there isn’t bad oil for a Subaru.
As to my selection of new oil I'm stuck with a slight quandary. Here in Texas driving a 4cyl turbo spiritedly with full intention of track days I seriously don't consider a 30 weight oil as up to snuff. However choosing a 40 weight or 50 weight becomes difficult as I try to meet the necessary oil requirements for Subaru's warranty (primarily API-SL and GF-3). As John Browning has indicated there is a host of very capable oils out there but meeting these two specs thins the field down significantly. I also have no desire to pay a significant premium for synthetic oil that I have zero intention of running an extended drain period on due to my driving patterns. While this vehicle will not necessarily be my daily driver I expect it to see some 30% to 40% of my daily driving taken in this vehicle. And at a round trip of 5 miles to and from work I easily fall into what is considered harsh driving environment by Subaru with recommended drain intervals of 3.7k. And when the vehicle isn't being driven as a semi-daily driver or the occasional highway diversion it will be run hard at track days and club drives. So when I went out looking for replacement oil I wanted a dino oil that was readily available from local stores. As it turns out the only 40 weight dino oil to meet both of the Subaru warranty concerns was the Castrol GTX.
As to the concerns of varnish with Castrol GTX I’ll take that into consideration. We must note however that this is a new API-SM/GF-4 formulation that may very well behave quite differently then prior oils. BITOG has the nasty habit of writing off something as bad only to never revisit the subject again due to “legends” despite changes having taken place. I plan to continue running UOAs for the entire time I own this vehicle so if any signs of varnish or sludge begin to appear I won’t be taken unawares. Also the 2.0L and 2.5L Subaru engines have so far had an excellent wear record even up into the 150k+ territory. It may very well turn out that there isn’t bad oil for a Subaru.
Tanji, I am going to send the Subaru police out to get ya! If that does not work we will have a Subaru owners against the use of GTX "intervention"! If they do not do interventions were you live I have to fly over their myself!!!
Drew99GT varnish and sludge are too different things! Castrol GTX is not a good oil! It is to oil what Fram is to oil filters. Niether one are bad they just are not good!
Tanji, That is true the GTX that my family used prior to me converting them over to synthetics was circa 1971-1990 or so 10W40 and 20W50 GTX changed at 1800 miles intervals. Even with this type of interval we still sometimes developed varnish on some engines. The filter of choice back in those days was the atomic orange can labled Fram!
Drew99GT varnish and sludge are too different things! Castrol GTX is not a good oil! It is to oil what Fram is to oil filters. Niether one are bad they just are not good!
Tanji, That is true the GTX that my family used prior to me converting them over to synthetics was circa 1971-1990 or so 10W40 and 20W50 GTX changed at 1800 miles intervals. Even with this type of interval we still sometimes developed varnish on some engines. The filter of choice back in those days was the atomic orange can labled Fram!
Tanj: Let me give you my $.02 worth on this. I don't have a problem with the brand or weight of oil you are using, but what concerns me is the fact you are using a dino oil. True, you can run just about anything in the Subie engine and it will last, but for the sake of the turbo and your sprited driving, I would highly recommend you use a full synthetic oil. Go to your local Wal-Mart and purchase some Mobil 1 0W40 or 5W40. Your turbo will thank you. And, if you like Castrol, then use their synthetic 5W40. I've owned several Subaru's and believe me, the synthetic make a big difference on the turbo. My wife now drives the Forester X without turbo and I run Pennzoil 5W30 with no reservations. But if it were a turbo, well that's a different story. Take care of it, they are great little vehicles.
Triple_Se7en
$50 Site Donor 2024
Castrol GTX is not a good oil!
Hhmmm... I disagree!
You may have issues with it & should probably have stated you don't like it instead. I know of posters at the site that reached 300K with it with no valve or ring problems (no smoke - little top-off). Most issues with name-brand dinos usually involve choosing the wrong weight for your vehicle, over-stepping the OCIs that fit the vehicle, overheating the engine due to poor driving habits, running too rich of a fuel mixture (sensor problem) & not changing filters/PCVs regularly.
[ April 19, 2005, 04:14 PM: Message edited by: Triple_Se7en ]
Hhmmm... I disagree!
You may have issues with it & should probably have stated you don't like it instead. I know of posters at the site that reached 300K with it with no valve or ring problems (no smoke - little top-off). Most issues with name-brand dinos usually involve choosing the wrong weight for your vehicle, over-stepping the OCIs that fit the vehicle, overheating the engine due to poor driving habits, running too rich of a fuel mixture (sensor problem) & not changing filters/PCVs regularly.
[ April 19, 2005, 04:14 PM: Message edited by: Triple_Se7en ]
I also used dino oil until 10k miles in my 2004 WRX. Changed out the factory fill to Mobil 10w-30 @ 2600 miles, then to Chevron 10w-40 @ ~5600 then again @ 7500. Switched to M1 T&SUV @ 10k. And it is perfectly fine to use 10w-40 in Texas heat. In fact, 40w is what every one else use in the world.
I only suggestion I have with Tanj keep the dino changes at short intervals of 3000-3750 miles before you switch to synthetic at 10k. Your engine is still breaking in afterall.
And my UOA is located somewhere in here...
I only suggestion I have with Tanj keep the dino changes at short intervals of 3000-3750 miles before you switch to synthetic at 10k. Your engine is still breaking in afterall.
And my UOA is located somewhere in here...
I'm 100% with Johnny. As a turbo owner myself you should use a real syn. Plenty of good 5W40 out there. We have an Outback as well but a turbo Forrester would do me nicely.
This is similar to what I'm doing with my '05 STi. Dropped the factory fill at 2,800 miles (changed to Mobil Drive Clean 5w-30). Ran that for 2,500 miles, replaced with Motorcraft 5w-30 semi-syn. Currently on the last 100 miles with this oil. Changing it out at 7,500 miles for Mobil 7500 semi-syn (10w-30), running that for 2,500 miles. Finally at the 10,000 mile mark I'll be switching over to German Castrol. I suspect the engine will still be breaking in at that point, but I'm really itching to get the GC in the car.
Shell Rotella T Synthetic (Wallmart) is an SL rated 5w-40 at only about $13 a gallon. Its a group III oil, but very high quality. No shearing in my use.
Tanj, while I won't go as far as JohnBrowning, I will say you could do better with a better brand of oil.
Chevron Supreme, Pennzoil and perhaps even Havoline would hold up better than Castrol GTX ... who's reputation among high-performance gearheads is mostly due to aggressive marketing.
I can't imagine the newer formulations will have the 'cleanliness issues' often associated with some of Castrol's older formulas.
However, the wear showing in your samples is 90+% because of break-in. You are simple not going to get really sweet numbers until that silicon number gets to be around 10 PPM or less.
I agree with frequent changes in the first 10,000-12,000 miles.
The moly in this factory fill is not as high as some Hondas (~1,000 PPM) and I can't imagine it's merely due to moly-coated factory parts. Got to be a special factory oil or a lot of moly in the assembly lube.
I will be a contrarian to most here and say that if you plan on changes every 3,000 miles, a SM/GF4 Group II+ base mineral oil (Chevron & Pennzoil) will be fine for the intended interval ... even in a turbo engine.
--- Bror Jace
Chevron Supreme, Pennzoil and perhaps even Havoline would hold up better than Castrol GTX ... who's reputation among high-performance gearheads is mostly due to aggressive marketing.
I can't imagine the newer formulations will have the 'cleanliness issues' often associated with some of Castrol's older formulas.
However, the wear showing in your samples is 90+% because of break-in. You are simple not going to get really sweet numbers until that silicon number gets to be around 10 PPM or less.
I agree with frequent changes in the first 10,000-12,000 miles.
The moly in this factory fill is not as high as some Hondas (~1,000 PPM) and I can't imagine it's merely due to moly-coated factory parts. Got to be a special factory oil or a lot of moly in the assembly lube.
I will be a contrarian to most here and say that if you plan on changes every 3,000 miles, a SM/GF4 Group II+ base mineral oil (Chevron & Pennzoil) will be fine for the intended interval ... even in a turbo engine.
--- Bror Jace
No, I believe you're thinking of the Mobil Drive Clean shearing issue that both I and Tim had on our STi's. I don't believe any of the STi owners who post here on BITOG have run Mobil 7500 in their STi yet.
My UOA:
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=3;t=002305
Tim's UOA:
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=1;t=009004
Good UOAs from Chevron and Pennzoil on this site? Is that a joke?
Here's a few:
Chevron:
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=002498
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=001922#000000
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=001851#000000
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=001639#000000
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=001110#000000
Pennzoil:
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=002497#000000
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=3;t=002358#000000
It just seems to me that Castrol is a touch more shear prone than the above brands. Maybe it's because the last I heard it was using 'only' a Group II oil instead of the more advanced Group II+ used by Chevron and Pennzoil?
I don't think any brand is bad. it's just that I think Chevron and Pennzoil are among the best mass-market brands ... better base oils and additive packages compared to Castrol GTX.
--- Bror Jace
Here's a few:
Chevron:
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=002498
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=001922#000000
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=001851#000000
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=001639#000000
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=001110#000000
Pennzoil:
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=002497#000000
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=3;t=002358#000000
It just seems to me that Castrol is a touch more shear prone than the above brands. Maybe it's because the last I heard it was using 'only' a Group II oil instead of the more advanced Group II+ used by Chevron and Pennzoil?
I don't think any brand is bad. it's just that I think Chevron and Pennzoil are among the best mass-market brands ... better base oils and additive packages compared to Castrol GTX.
--- Bror Jace
- Status
