GC 0W30 5,163 miles 03 VW Passat 1.8T

[parrothead]

This is my first run of GC. The previous colums from left to right are Pentosynth 5W40, Amsoil 5W-40, Mobil 1 0W-40 and Mobil 1 0W-40. The GC was in use for approximately 4 months. The car sees 50/50 mix of city and highway driving. There were some very cold (way below 0 F) during the 4 months this oil was in use. I'm pretty happy with the results, especially when you compare them to the Mobil 1 results from last winter.

 

[Al]

Good information. Your car is a model of consistancy and its obvious that 30 wt. is doing fine. True to its reputation, Mobil didn't disapoint with its high irons (which may or may not be due to wear)

Did your milage go up with the 30 wt.??

 

[wavinwayne]

parrothead,

What brand/part # oil filter are you using? What brand/part # oil filter(s) did you use previously on your VW?

Thanks in advance.

 

[jthorner]

Sure enough, the only thing that stands out is that the non-Mobil1 oils consistently returned significantly lower Iron numbers than did the Mobil-1 reports.

We have seen this enough times, but not all the time, as to really make a person wonder what is going on visa-vis Mobil-1 and Iron in UOAs.

John

 

[buster]

quote:

---

True to its reputation, Mobil didn't disapoint with its high irons (which may or may not be due to wear)

---

I know and it sucks doesn't it.

Wish we knew what it was. Otherwise, great report.

I personally think it's corrosion.

 

[parrothead]

I did not notice an improvement in mileage with the 30 wt oil. All of my 40 wt runs, except for Amsoil, thinned down to near 30 wt.

I've been using Mann oil filters from ECS Tuning. The part number is W71930. When I changed my oil this time around I used the new larger recommneded filter. Still a Mann filter from ECS, but part number W94025. I'll have to wait until my next UOA to see what kind of difference, if any, the larger filter makes.

 

[jthorner]

quote:

---

I personally think it's corrosion

---

Why do you think so? The simple explanation would be valve train wear. All other explanations require a lot more mental contortions to justify.

John

 

[buster]

quote:

---

Why do you think so?

---

If you look at all oils today, they all have low ZDP levels. Mobil 1 has a nice additive package. It's as likely of an explanation as wear.

 

[TooSlick]

Parrothead,

What was the TBN and viscosity of the Amsoil 5w-40 after 5000 miles? I'm running it in my Audi TT roadster at the moment....

thanks!

Ted

 

[TooSlick]

BTW, I think Buster is correct about the corrosive wear....

Iron levels with Mobil 1 tend to be significantly higher in cold weather. There is more of a variance that I typically see with other brands. Note these mobil 1 formulations were tested in Feb and Dec, respectively (in Michigan)....

Hint: This may be why they bumped up the boron levels in their EP formulations...

TS

 

[parrothead]

TS, the TBN of the Amsoil was 5.1 and the SUS viscosity was 78.4. As I said above the other xw-40 oils thinned a bit, but Amsoil appeared to thicken a bit.

 

[TooSlick]

Thanks ...I'm actually surprised it didn't shear in this application....I'll be interested to see how it does in my 225 Hp Audi TT.

TS

 

[parrothead]

TS, I was also surprised that the Amsoil did not shear. It also appears that GC held its viscosity pretty well. Overall I'm pretty happy with my last 3 UOA's and feel that I now have a couple of excellent oils to chose from.

 

[VeeDubb]

At 78.4, I'm not sure the Amsoil thickened. Doesn't it start at around 80? I'd call it remarkably shear stable.

 

[parrothead]

VeeDub, good question on the Amsoil. According to Amsoil's website that oil is listed as having a viscosity of 14.5 cSt at 100 C. Doesn't that convert to something like 76 SUS? Either way it appears to be very shear stable compared to the M1 or Pentosynth when run in my engine.

 

[TooSlick]

An unused sample of the Amsoil 5w-40 I had tested @ Blackstone came in @ 77.2 SUS, as I recall. So it really didn't change at all; given the accuracy of the ASTM viscosity test....

TS

 

[Bill]

TooSlick,

On the Amsoil website, the product data sheet for the 5W-40:

Kinematic Viscosity @ 40°C, cSt (ASTM D-445)= 83.6


Maybe Amsoil recently changed the base stock viscosity and the data sheets are not up to date?
or
if there is that much difference in testing from one lab to another?

 

[Bill]

Opps!

TooSlick alerted me that I am comparing SUS to Cst,

disregard my reply above.

Thanks TooSlick