IS Castrol GC 0w-30 A Powerful Cleaning Oil ?

Messages
922
Location
Ontario , Canada
My car starting using more oil than usual a few months ago. I was running Mobil1 10w-30 for most of the car's 2 year life, interspersed with some Redline oil runs. It started using a full quart of oil between 3,000 mile OCI's earlier this year, when it usually would never use more than 1/2 a quart at most. I ran Redline 10w-30 on the 2nd last OCI to see if it would have any effect and it also used a full quart of Redline oil on that run. My last run I decided to use Castrol GC 0w-30, the car used a bit less oil on that run, maybe .75 quarts or slightly less. I've now gone back to Mobil1 10w-30 and it hasn't used a drop in 1,000 miles. The reason I went back to Mobil1 is because I find the engine is more responsive and seems to run smoother on Mobil1. The Castrol ow-30 seemed to make the engine more sluggish. So I'm wondering if the Castrol GC had cleaned up some sticky rings or something. I thought the Redline would have done that more than the Castrol but things seemed to have changed after the Castrol GC run. I know recent Castrol ads in auto magazines tought its cleanliness attributes, but who really knows. The only thing that has changed recently is that I changed to a hotter set of spark plugs, my previous plugs were a tad too cool (heat range wise) so I went back to a hotter plug. The engine is a 2.4L turbo, which runs very rich at wide open throttle and high rpms. any opinions would be cool. thanks !
 
Messages
11,247
Location
PA
I cut open my filters after ARX...after 2 11k runs of GC and there was nothing there. Weather it cleaned or there was nothing to clean or whatever...it was a hi-miles car.
 
Messages
5,358
Location
Gone
I think it is formulated to do a good job of keeping things clean...now as to whether it is a "powerful" cleaning oil...I think it can hold its own with just about any oil on the market.
 
All the oils you have been using are oils that should keep your engine clean. I found that Mobil 1 is one of the best. I had a 95 Landcruiser at 100K I did a valve adjustment and it looked like new. I found that using Mobil 1 or Amsoil synthetic it would use about 1 quart between 5K mile oil changes. I would not worry about your engine using a quart every 3K miles. Its a small engine that works hard and using some oil is not a bad thing. Keep using the Mobil 1
 
Messages
624
Location
Colorado, US
GC is good oil, with some kinda "not-toally-understood" base stock... I mean, in theory, it's different than your typical amsoil/mobil1 basestocks... But i'd be suprised to hear that GC did any *more* cleaning than redline could. (redline is known here for keeping engines spotless, lots of group 5 basestocks. ester oils) The add-pack of GC, is said to be, similar, to that of HDEOs (not quite, but close)... so it certainly has the potencial to do some cleaning or keep things clean or run extended intervals. Major cleaning, is typically only achieved by some form of addative. (arx/lc)... I have a theory however.. to the possability of cleaning taking place... I have heard- that, perhaps, some of the cleaning that arx does, is based on polarity changes... (penetrate crud with heavily polerized ester oils, then "rinse" them away with non-polerized oil).. So, you ran an interval with redline, which is probably significantly polerized, being group5 ester... then switched oil.. to GC- GC being an oil with lesser-understood base stocks, perhaps it is less polerized, and washed away some of your recently polerized sludge? maybe someone could chime in on this- this is just a theory i'm having, kinda a guess... don't take it as fact, but it's the only thing that comes to mind, based on what I have read here on bitog.
 
Messages
552
Location
Tennessee
Anyone who has been using GC for a significant number of miles, care to show us photos of what is under your (valve) covers? That might answer the cleaning question. I have seen high mileage pictures of Redline and Mobil 1 engines almost clean enough to eat from - with the valve covers removed.
 
Messages
5,358
Location
Gone
I have seen high mileage pictures of Redline and Mobil 1 engines almost clean enough to eat from..." With GC, no need to eat from the valve covers...you can drink it straight from the bottle. [Big Grin]
 
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