Troubling UOA

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One other note: if there is a severe service schedule in your owners manual, that's definitely where you need to be. 70% aggressive city driving does not a long OCI make.
 
Originally Posted By: ram_man
Originally Posted By: JMarshall
Originally Posted By: ls1mike
What is cheaper? An engine or a couple of extra oil changes a year. I would not go 10K.


Definitely the oil. If I'm sitting on a ticking time bomb though, I want to trade it in before [censored] hits the fan.

Originally Posted By: simple_gifts
I don't know squat, but I'd do what B-S suggests; if a 5K interval produces 1/4 the wear...

I'd try to establish whether the wear is linear, or geometric etc.


Will do a couple shorter OCIs and see what it does.

Originally Posted By: volk06
Your engine has only had 3 oil changes in 30K. Thats about 3-5 less OCIs than the average person. While your wear is high its due to the long OCIs and the engine breaking in. If you want to see if you can get lower wear, do a few short OCIs and then sample. That oil looks WEAK as well. What oil is specified for this engine? It looks like it needs to move up to M1 0w40 if that is an approved oil. I'm assuming this is a diesel engine?


This is a 2011 VW Jetta TDI. I am running both the 10K mile oil changes specified by VW, as well as the Castrol SLX Pro LLO3 full synthetic 5W-30 that is both specified and factory.

Originally Posted By: spasm3
Did coolant somehow get in the oil? The K+ is lower but was really high initially.


I have had no coolant loss or leakage.

Originally Posted By: ram_man
3,000 mile oci never hurt anyone.


Actually, multiple UOAs have found that shorter intervals can actually increase wear in these VW TDIs


Funny you mention that when your engine is wearing the way it is. You show me one engine that failed because of 3,000 oil changes and ill back off my point. Just because a bunch of lab coat wearing scientist's say something doesn't mean its true. Ive seen uoa be very inconsistent with what they should be. Also werent scientists the same people who said pluto wasnt a planet and then it was and then it wasnt again? Like I said 3000 oci never hurt anyone.


To be fair, I'd like you to show me one engine that failed because of 5,000 mile oil change intervals; actually, show me one engine that failed because of 7,500 mile oil change intervals. 3,000 mile OCI's in MOST applications is a waste - moving on...
11.gif


IMO, you should change the oil to a stouter, approved oil, run two shorter intervals, and then sample after the third shorter interval. I'm going to go out on a limb and speculate that your engine is just fine, and only needs a proper oil at a proper interval.

Also, while you say you drive 70% city, you're also putting a lot of miles on the car - 10k miles in < 6 months doesn't sound like this engine spends too much time at low temps.
 
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Part of the problem may be a combination of your driving habits and the use of a biodiesel blend. There are definitely lots of instances where the use of biodiesel in the TDI increases the likelihood of fuel dilution of the motor oil. Fuel dilution is also a strong possibility when you're doing a lot of short trips. Do you have access to regular D2? I'd also shorten the OCI like everyone suggests to try to get the metals down/out. Once you isolate the problem you can start to extend the OCI back to the manufacturer interval.
 
Originally Posted By: gathermewool
Originally Posted By: ram_man
Originally Posted By: JMarshall
Originally Posted By: ls1mike
What is cheaper? An engine or a couple of extra oil changes a year. I would not go 10K.


Definitely the oil. If I'm sitting on a ticking time bomb though, I want to trade it in before [censored] hits the fan.

Originally Posted By: simple_gifts
I don't know squat, but I'd do what B-S suggests; if a 5K interval produces 1/4 the wear...

I'd try to establish whether the wear is linear, or geometric etc.


Will do a couple shorter OCIs and see what it does.

Originally Posted By: volk06
Your engine has only had 3 oil changes in 30K. Thats about 3-5 less OCIs than the average person. While your wear is high its due to the long OCIs and the engine breaking in. If you want to see if you can get lower wear, do a few short OCIs and then sample. That oil looks WEAK as well. What oil is specified for this engine? It looks like it needs to move up to M1 0w40 if that is an approved oil. I'm assuming this is a diesel engine?


This is a 2011 VW Jetta TDI. I am running both the 10K mile oil changes specified by VW, as well as the Castrol SLX Pro LLO3 full synthetic 5W-30 that is both specified and factory.

Originally Posted By: spasm3
Did coolant somehow get in the oil? The K+ is lower but was really high initially.


I have had no coolant loss or leakage.

Originally Posted By: ram_man
3,000 mile oci never hurt anyone.


Actually, multiple UOAs have found that shorter intervals can actually increase wear in these VW TDIs


Funny you mention that when your engine is wearing the way it is. You show me one engine that failed because of 3,000 oil changes and ill back off my point. Just because a bunch of lab coat wearing scientist's say something doesn't mean its true. Ive seen uoa be very inconsistent with what they should be. Also werent scientists the same people who said pluto wasnt a planet and then it was and then it wasnt again? Like I said 3000 oci never hurt anyone.


To be fair, I'd like you to show me one engine that failed because of 5,000 mile oil change intervals; actually, show me one engine that failed because of 7,500 mile oil change intervals. 3,000 mile OCI's in MOST applications is a waste - moving on...
11.gif


IMO, you should change the oil to a stouter, approved oil, run two shorter intervals, and then sample after the third shorter interval. I'm going to go out on a limb and speculate that your engine is just fine, and only needs a proper oil at a proper interval.

Also, while you say you drive 70% city, you're also putting a lot of miles on the car - 10k miles in < 6 months doesn't sound like this engine spends too much time at low temps.



well its not all out failure but the saturn s series if not given 3000 mile oci will burn oil. Alot get so bad its like every tank of gas add a quart. And the only fix is a rebuild.
to say 3,000 mile oci increase wear is insane is my point. Is it a waste in most applications ? Yes I think so. However having one uoa after another that is bad. I would go back to 3,000 and see how it looks if its good then let it go a little longer but I would rather run it a little short and waste a little oil versus running to long and decreasing engine longevity.
 
I won't comment on a diesel UOA, but did Blackstone switch to GC for fuel dilution determination.

If you value your TDI, then send your reports to Terry Dyson for interpretation and recommendation.
 
All of the approved oils for this car are 5/30, Castrol SLX Professional (gold bottle) is the dealer oil. It doesn't have a great reputation in TDi circles.

Mobil 1 has an approved oil (ESP) as does LiqiMoly they are probably the 3 easiest to find.

I'd probably sample at 5000 (not necessarily change) and see how it does.

Also might not be a bad idea to get it on record with VW.
 
Originally Posted By: rhhsiao
Part of the problem may be a combination of your driving habits and the use of a biodiesel blend. There are definitely lots of instances where the use of biodiesel in the TDI increases the likelihood of fuel dilution of the motor oil. Fuel dilution is also a strong possibility when you're doing a lot of short trips. Do you have access to regular D2? I'd also shorten the OCI like everyone suggests to try to get the metals down/out. Once you isolate the problem you can start to extend the OCI back to the manufacturer interval.


No, all diesel in PA is B5 by mandate
 
Originally Posted By: JMarshall
Originally Posted By: rhhsiao
Part of the problem may be a combination of your driving habits and the use of a biodiesel blend. There are definitely lots of instances where the use of biodiesel in the TDI increases the likelihood of fuel dilution of the motor oil. Fuel dilution is also a strong possibility when you're doing a lot of short trips. Do you have access to regular D2? I'd also shorten the OCI like everyone suggests to try to get the metals down/out. Once you isolate the problem you can start to extend the OCI back to the manufacturer interval.


No, all diesel in PA is B5 by mandate


I'd go with a short OCI, probably 5K miles, and do another UOA to see how things are shaping up. The one positive takeaway is that wear metals are trending down save for iron but definitely not fast enough.
 
Originally Posted By: simple_gifts
Quote:

Did coolant somehow get in the oil? The K+ is lower but was really high initially.


Saw that but the glycol test is 0. Wonder if that is a valid test for VW coolant.


The big question is, why is the Potassium trending downward?

Did the FF oil contain a lot of Potassium agent?

What does the VOA of this current oil show in terms of Potassium?
 
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Originally Posted By: MolaKule
Originally Posted By: simple_gifts
Quote:

Did coolant somehow get in the oil? The K+ is lower but was really high initially.


Saw that but the glycol test is 0. Wonder if that is a valid test for VW coolant.


The big question is, why is the Potassium trending downward?

Did the FF oil contain a lot of Potassium agent?

What does the VOA of this current oil show in terms of Potassium?



The first few UOAs of the common rail diesels from VW all tend to show high potassium. I believe it's from the EGR system or the use of a welding flux.
 
What does anyone think of the plan of pulling a sample through the dipstick tube @ 4500 miles and seeing how it looks then?
 
Originally Posted By: demarpaint
10K OCI is too long, forget the owners manual, cut the interval in half and see how thing pan out. Just out of curiosity do you have an OLM? If so how long before it triggers an OCI?


It doesn't have oil life sensors like say a GM product. It has a service indicator that comes on after a set mileage/time regardless of driving habit/etc
 
Originally Posted By: JMarshall
What does anyone think of the plan of pulling a sample through the dipstick tube @ 4500 miles and seeing how it looks then?


I'd say just drain it, obtaining a sample midway through. If money is an issue, then do a couple of shorter (5-6k) OCI's without sampling, and then send out a sample of the third drain for analysis. The reason I suggest this, is because residual wear-like metals will still be present from previous intervals, so even if the oil looks fine after this run to 4,500 miles, the "wear" metals may erroneously appear alarmingly high. They should, however, trend downward due to dilution, the end of break-in, and less run time.

Also, remember that most diesel guys that I've talked to (note, I am NOT a diesel guy) don't consider their engines broken in until well after a gasser would be.
 
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Originally Posted By: gathermewool
Originally Posted By: JMarshall
What does anyone think of the plan of pulling a sample through the dipstick tube @ 4500 miles and seeing how it looks then?


I'd say just drain it, obtaining a sample midway through. If money is an issue, then do a couple of shorter (5-6k) OCI's without sampling, and then send out a sample of the third drain for analysis. The reason I suggest this, is because residual wear-like metals will still be present from previous intervals, so even if the oil looks fine after this run to 4,500 miles, the "wear" metals may erroneously appear alarmingly high. They should, however, trend downward due to dilution, the end of break-in, and less run time.

Also, remember that most diesel guys that I've talked to (note, I am NOT a diesel guy) don't consider their engines broken in until well after a gasser would be.


These engines normally aren't "broken in" and hit their peak compression numbers until ~60K miles. So you would just change it a couple times without sampling? Money isn't really an issue. My thought was at 4500 miles, if this high number was a fluke from catching oil out of the bottom of the pan, etc, that sampling at 4500 would allow me to still run the oil if it is in good shape, or change it out if need be.
 
Originally Posted By: JMarshall
Originally Posted By: gathermewool
Originally Posted By: JMarshall
What does anyone think of the plan of pulling a sample through the dipstick tube @ 4500 miles and seeing how it looks then?


I'd say just drain it, obtaining a sample midway through. If money is an issue, then do a couple of shorter (5-6k) OCI's without sampling, and then send out a sample of the third drain for analysis. The reason I suggest this, is because residual wear-like metals will still be present from previous intervals, so even if the oil looks fine after this run to 4,500 miles, the "wear" metals may erroneously appear alarmingly high. They should, however, trend downward due to dilution, the end of break-in, and less run time.

Also, remember that most diesel guys that I've talked to (note, I am NOT a diesel guy) don't consider their engines broken in until well after a gasser would be.


These engines normally aren't "broken in" and hit their peak compression numbers until ~60K miles. So you would just change it a couple times without sampling? Money isn't really an issue. My thought was at 4500 miles, if this high number was a fluke from catching oil out of the bottom of the pan, etc, that sampling at 4500 would allow me to still run the oil if it is in good shape, or change it out if need be.


I personally like this idea of sampling mid-run from the dipstick. There definitely could also be the possibility of contamination if you were getting samples from the bottom. I personally have a suspicion the oil itself is fine but a combo of break-in wear, biodiesel, cold weather starts, and hard driving are giving you wear numbers that look bad this early in the life of the engine. But what do I know? It's all really conjecture at this point anyway.
 
More data is always better, so if you don't mind, we'd all love to see a sample at ~4,500 miles. If the results trend downward, then you can decide what your interval should be, based on how steep the trend is.

I wouldn't assume the numbers from the most recent analysis are bad - trust your indications. That doesn't mean to trust them blindly, which is why your verification sample isn't a bad idea at all. Worst case is, you drain the oil as soon as you receive the analysis results.
 
10k miles is not an unusual interval for an oil change on the current TDI diesels. There is certainly something else going on here. The VW TDIs don't perform forced regens of the the particulate filters so an excess of fuel in the oil is an indication of a fuel injection problem. I would take the car back to the dealer and ask them to confirm the injectors are performing properly.
What kind of fuel mileage are you getting? A current TDI should be seeing 30+ mpg city and nearly 40 on the highway at the least.
 
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I will pull a sample at 4500 and see what happens.

Originally Posted By: Radiation_Joe
10k miles is not an unusual interval for an oil change on the current TDI diesels. There is certainly something else going on here. The VW TDIs don't perform forced regens of the the particulate filters so an excess of fuel in the oil is an indication of a fuel injection problem. I would take the car back to the dealer and ask them to confirm the injectors are performing properly.
What kind of fuel mileage are you getting? A current TDI should be seeing 30+ mpg city and nearly 40 on the highway at the least.


I am getting the same mileage I always have, 33-35 in the city and 43 on the highway.
 
Aluminum, Copper, and Potassium have been trending down since new.
Chromium has been steady.
Iron jumped in the last UOA, along with the fuel.
The KV100 is borderline 20-weight.
The flashpoint is 50F lower than the last UOA.
The Castrol SLX 5w30 looks weak in both anti-wear and detergency.

Go to a thicker oil with higher anti-wear and shorten the OCI.
Since your car has a particulate trap, M1 5w40 ESP Formula M on a 5000 mile drain may be good.
Since the fuel dilution just started, I would take the UOA result to the VW dealer, get the issue on the record, and see if there is anything they can do about it.
 
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