Castrol GTX 5w30, 9750 miles OCI, 2000 Mustang 3.8

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I have concluded that conventional oil can go long distances, that my engine will run much longer than my chassis and that running high dollar synthetics and then changing them out below 10k is a waste of money..... I have a 2000 Ford Mustang. I knew the first owner. Her OCI was 4-5k and she sold it to me at 109k. My OCI has been 5-7k. Now I will go 8k+ Look at these numbers. I realize a naturally aspirated 3.8 V6 is not nearly as valuable as a lot of engines on here, but synthetic seems like overkill for most people. By the way, at the recent change, I was down a full quart, so I'm thinking if I had refreshed it with a quart that week, my numbers would have been 20% lower. It was at the right level on the previous change at 7500 miles. This is mostly around town miles, although not heavy city driving. http://www.mediafire.com/file/oudefrz1zzb/MustangOil62509.pdf
 
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Iron is fine for almost 10k on dino. May want to run a lighweight HDEO instead of the weak castrol. Need a TBN at this kinda push on a dino though.
 
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You have to be careful with carbon build up around the rings with a OCI over 5,000 miles with dino, any kind.
 
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I would be leery without knowing TBN. Higher wear might have been from worn out oil. That also doesn't tell anything about cleanliness of engine.
 
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I agree that modern dino can go a long way. I've done numerous 8-9k runs on dino oil, and my last UOA was great. Insols. and visc. are great for that length of a run! Good show!
 

Dave_Reagan

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I will probably go 8k next time. Keep in mind that I was down a full quart, so by my logic, if I had added that quart a day before, my metals numbers would have been ~20% lower. I refilled with Castrol GTX 5w20, which is what I ran in the first UOA. ThirdeYe, thank you very much for deleting my personal info. Do you have a paying version of Acrobat? Standard fram filter was used. The TBN is an extra $10 and it was in good shape at 7500 miles last time, so I skipped it. Can anyone offer a compelling reason to run a synthetic? I'm actually tempted to run some Walmart oil and see what it looks like at 6k.
 
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One reason to run synthetic: cold-weather start-up help. I'm thinking of running syn this winter for that reason only.....
 
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 Originally Posted By: Dave_Reagan
I will probably go 8k next time. Keep in mind that I was down a full quart, so by my logic, if I had added that quart a day before, my metals numbers would have been ~20% lower. I refilled with Castrol GTX 5w20, which is what I ran in the first UOA. ThirdeYe, thank you very much for deleting my personal info. Do you have a paying version of Acrobat? Standard fram filter was used. The TBN is an extra $10 and it was in good shape at 7500 miles last time, so I skipped it. Can anyone offer a compelling reason to run a synthetic? I'm actually tempted to run some Walmart oil and see what it looks like at 6k.
It's no problem. \:\! I can't remember exactly where I got Acrobat. I think it came with my Photoshop but I could be wrong.
 
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 Originally Posted By: Dave_Reagan
I will probably go 8k next time. ThirdeYe, thank you very much for deleting my personal info. Do you have a paying version of Acrobat?
You can right click "open with" the PDF with MSPaint and erase or airbrush over the personal stuff using the tool box on the left. Why dont you try some syn thats on sale (cheaper than dino) and run a killer oil filter (m1, Pureone, Fram extended guard, Bosch w/ filtech) and see if we cant get that FE down to trace. A grp-iii base oil would be better than a PAO for that. Looks good though
 
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Great White North.. eh
I know we all like to extend oci's and get our money's worth. However, I wouldn't go past 7k with gtx. I don't believe that a 10k mile oci with regular dino is 'ok' except under the rarest of circumstances.
 
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 Originally Posted By: ARCOgraphite
run a killer oil filter (m1, Pureone, Fram extended guard, Bosch w/ filtech) and see if we cant get that FE down to trace. A grp-iii base oil would be better than a PAO for that.
Pure speculation and guessing is not what BITOG is all about. So first we will need the data that those oil filters will lower Fe , then we will be waiting for the data that shows a group III base oil produces lower Fe in UOA's than Group IV based oils.
 
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 Originally Posted By: addyguy
I agree that modern dino can go a long way. I've done numerous 8-9k runs on dino oil, and my last UOA was great. Insols. and visc. are great for that length of a run! Good show!
It's my understanding your engine can be worn out but the UOA can still look good. The guy with the turbo buick here on BITOG has reported this.My advise is don't go past 5,000 miles on any dino.
 
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 Originally Posted By: tig1
 Originally Posted By: addyguy
I agree that modern dino can go a long way. I've done numerous 8-9k runs on dino oil, and my last UOA was great. Insols. and visc. are great for that length of a run! Good show!
It's my understanding your engine can be worn out but the UOA can still look good. The guy with the turbo buick here on BITOG has reported this.My advise is don't go past 5,000 miles on any dino.
It is nice to see people on here still know more than Honda and the likes.
 
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