There's no need to flush, as your engine is clean. If you plan to change oil brands, and the new oil company has a flush, and it would make you feel better, flush to 'neutralize' the last of the oil oil that will remain in the engine.dhdenney said:BTW, should I use an engine flush such as Motul before switching oils? Or should I run the short 3K interval, then do a flush?
I think you mean that if either oxidation or nitration is over 50 it's time for a change?TornadoRed said:I have read somewhere that if oxidation plus sulfation equals 50 or greater, it's time for an oil change.
Okay, it was here: http://www.oaitesting.com/g2047.pdf
Given that you didn't get a TBN value, OXID + SULF may give you an approximate idea of the acidity of the oil. Yours is considered "excessive".
It does say that, doesn't it?AndyH said:I think you mean that if either oxidation or nitration is over 50 it's time for a change?
Point taken. I still think 80+ppm Fe for recommended OCI is a tad high (certainly not terrible), regardless of conditions.AndyH said:A comment on comparing UOA reports...
UOA is a trending tool and is only valid for that specific engine. No two engines are identical, no two cars are identical, and no two drivers are identical.
UOA is a great diagnostic tool, but it is not a valid oil comparison tool. If it were, there'd be no need for ASTM tests or engine test stands.
IMHO, I don't run it hard. But that's a subjective term. Perhaps I do run it hard. So ideally soot should be down around .5 after 10K? Maybe it's in my oil instead of my EGR.Long_Range said:dhdenny;
Do you run this car a bit hard? Usually that's the case with high soot. I make 1% per 10K miles myself.
Not so much for that purpose, just wanted to get some residuals out. I always use a Pela and next time I am going to use a bottom drain and Pela to suck out oil cooler/housing. I am not necessarily switching oil, I am out of everything (oil leak zapped the remaining qts I had) so I am gonna try LL3 for 10K and make a comparison for myself since I shouldn't necessarily compare UOAs with other users.AndyH said:There's no need to flush, as your engine is clean. If you plan to change oil brands, and the new oil company has a flush, and it would make you feel better, flush to 'neutralize' the last of the oil oil that will remain in the engine.
If the MAF shows up bad with a VagCom check the dealer techs will find the same when they check it.dhdenney said:I understand what you are saying about preempting the problem but with no light, I don't think I could do much in the warranty realm.
I had my car at the dealer yesterday. I should have ask if they would run a VAG COM on it. Doubt it though. I use almost exclusive BioWillie B20 so I would think that soot would be lower.Long_Range said:If the MAF shows up bad with a VagCom check the dealer techs will find the same when they check it.
I thought mine was still under emissions warranty so I foolishly took it into the dealership. They performed an extensive diagnostic. From their description it sounded just like the VagCom routine. They plugged in their laptop then two techs went for a drive. One man driving while the other ran the computer. WOT runs. I could even see the fuel gage had dropped some. They must have had a good time.
Dealership wanted $165 for the MAF and one hour labor. However they were sold out of MAFs after replacing two the day before. They cleared the CEL and it never came back on.
I realize I may be talking you into a bunch of work for nothing. But if you're going to diagnose a bad MAF I”d think you'd want to do it before 50K miles. Their has to be some reason for making more soot than some chipped cars.
BTW I'm still looking to see this drop in soot production we hoped for with ULSDF.
The last two changes have been Elf 5w-40, the one before that was a 505.01 "recommended" oil (46 on the iron), the 3 before that were Motul, and going back from there it was all Delvac 1. Car was chipped at 96.6k miles.Long_Range said:Nice numbers LVPAJetta. And on a chipped car to boot.
Did you get soot numbers with that? What oil ? You may want to post your cars specs. We are a nosey bunch after all.
I'd like to buy VAG COM but I just have so much I need to buy and I'm unemployed right now. Would be nice to get soot cut in half though. Not sure what to do about it.... My car doesn't smoke noticeably.Long_Range said:They may charge you an hour labor for checking the MAF. I paid $43.50 for the diagnostic. They only charged me a half hour but said they charge a full hour for a MAF plus the $168.10 for the part. tdiparts has PD MAFs for $125.
Just from driving mine I'd noticed it being a little sluggish and hard to get rolling without some clutch slippage. Before the CEL came on. So I suppose if your car runs smooth and doesn't smoke you could call it good. If you don't know anyone with a VagCom.
The oil reports I have are the four from Staveley. Two at 5000 miles, one at 9865, and the most recent at 6101. We know from other 505.01 results that the oil thins in service and appears to give it's worst wear numbers in the middle of the drain interval - and this is where most of your data is centered. Since it appears that the wear rate is not linear (some increase as the oil thins, a decrease in the last 1/2 of the interval), I see no reason to believe that you have more wear at the 46000 mile point.dhdenney said:Not so much for that purpose, just wanted to get some residuals out. I always use a Pela and next time I am going to use a bottom drain and Pela to suck out oil cooler/housing. I am not necessarily switching oil, I am out of everything (oil leak zapped the remaining qts I had) so I am gonna try LL3 for 10K and make a comparison for myself since I shouldn't necessarily compare UOAs with other users.
So to get an accurate representation, one should sample at say 2500, 5000, 7500, and then 10,000 miles for an accurate comparison?AndyH said:The oil reports I have are the four from Staveley. Two at 5000 miles, one at 9865, and the most recent at 6101. We know from other 505.01 results that the oil thins in service and appears to give it's worst wear numbers in the middle of the drain interval - and this is where most of your data is centered. Since it appears that the wear rate is not linear (some increase as the oil thins, a decrease in the last 1/2 of the interval), I see no reason to believe that you have more wear at the 46000 mile point.
Your rate of wear at the mid point of an oil change is running between 8.4 and 9.6 ppm iron per thousand miles (ppm/1k). Your last sample was 8.8 ppm/1K.
Your rate of wear later in a drain interval - one data point - is 8.3 ppm/1K.
To decide on an oil, based solely on wear rate, I'd plan on four intervals with one oil. Disregard any oil analysis results from the first interval as it's not going to be representative. Don't put much emphasis on mid-interval wear rates as you already know these will be higher than the overall interval. Don't bother with any engine flush in this instance - it's basically spending money to chase 1 or 2 ppm from the engine in order to possibly generate 1 or 2 ppm in new damage from additive clash. This is 'mouse nuts' or 'much ado about nothing', since we have a plus/minus 10% range for the same oil sample at the same lab.
How significant is 2 ppm when your 'ruler' can only measure to the closest 10 ppm? You have about +/- 5 ppm at the midpoint drains and about +/- 8 ppm at the end.
Andy
I think you should change it. The soot at 0.70% is getting up there, and the Fe at 89 ppm is very high even on a relatively low-mile engine.mparker326 said:Here is a Quaker State 505.01 UOA taken at 7500 miles. ... Mileage on Car - 27500...
Sample was taken with an extractor pump and the second sample was sent in. I took the sample after a 100 mile trip & 20 minute cooldown.
Oil has not been changed.