GC in '05 Mazda 3s ???

Messages
588
Location
Southern Oregon, USA
It's spec'd for 5w20... but I really don't think it's going to be enough. 2005 Mazda 3s 2.3L I'm about 75 - 80% highway driving (70-75mph), 60mi round-trip to & from work five days a week... so I think that it might be a pretty nice idea to get a "thicker" 30w oil in there... but I'm not sure. I'm currently on a run of the Mobil 1 EP 5w30, and it seems to be running well. It really quieted down the engine over the Motorcraft 5w20 that comes standard... and I don't notice any MPG difference. What do you guys think... lay it out for me... GC in my Mazda? Good or bad???
 
Messages
253
Location
Boston
GC is probably unnecessary, and may tank your mpg... I found it made my Subaru 2.5l engine noticeably sluggish compared to other oils (before and after GC)... it's on the thick end of the 30W range at operating temperatures. There are tons of great UOAs on Havoline 5W-20 and the lamentably-no-longer-available Mobil1 0W-20 in the Mazda 2.3l engines (mostly Mazda6's) If it were my car, I'd run Mobil1 5W-20 with Lube Control, and get a Dyson analysis to fine tune the OCI.
 
Messages
5,358
Location
Gone
I think it would be a great match ESPECIALLY given the type driving you do. Picture yourself (it will be easy if you are in western Oregon) blitzing down Bundestraßen 284 between Freudenstadt und Schiltach with all those little Nipponese cylinders singing a sweet Elfen melody.
 
Messages
253
Location
Boston
IMHO, highway driving is ridiculously easy on oil... it burns off any water condensation and fuel dilution you may have, and puts much less stress on your engine than stop and go city driving. However, I'm not an Elfe Meister... try it for yourself and see. But remember this... smart people learn from their mistakes, and really smart people learn from other people's mistakes!
 

sdude2k2000

Thread starter
Messages
588
Location
Southern Oregon, USA
quote:
Originally posted by bigpaulo: But remember this... smart people learn from their mistakes, and really smart people learn from other people's mistakes!
That's great and all... but how in the heck does that apply to me and this situation? [I dont know]
quote:
Originally posted by pscholte: it will be easy if you are in western Oregon
Actually... I am in southern oregon! [LOL!] But can you translate whatever the **** u said into a more... ENGLISH version? [Happy]
 
Messages
5,358
Location
Gone
Southern Oregon will probably work too...but in answer to your question...what the Elfemeister really said was...it will be perfect for your car, your climate and your described driving conditions...and for a longer OCIs.
 
Messages
625
Location
Silver Spring, MD (USA)
s2k, Since the 6i uses the same engine, here's a set of 6i UOAs to help you in your decision. http://www.mazda6tech.com/articles/maintenance/used-oil-analysis.html The 10w-30 and 0w-30's give you an idea of the viscosity effect on the car. Honestly, one owner just did a 0w-20, then a 10w-30, and the wear metals were basically identical. (He's in panama to boot, so obviously a pretty hot/humid climate) I'd stick with 20wt's myself and take the increase in revability and mileage. If you wanted an oil with a higher HTHS #, you could always run 5w-20 redline (3.3 vs 3.6 of GC)
 
Top