Mobil 1 VS. Rotella T6

truman

Top Post Dawg
Joined
May 18, 2000
Location
columbia,MO,usa
TDI
'05 Passat Variant, Still miss the 03JW
I talked to a few guys at my local O'reily's Auto Parts Store, and they said that they will price match Wal-Marts price on the TDT. (They carry it year round in all stores i guess)

Oreily's is 26 a gallon
Wal-mart is 21.

Rotella T6 is 18 at Walmart
And @ Tractor stores its 27.
O'Reilley's carries 5w40 Valvoline, which is "505.01 approved" for $3.99/qt. They also have 20w50, which the label states "meets the requirements of 505.01". $3.99/qt is less than $16/gal. That's the best deal going, as far as I can tell, for normal drain intervals.
 

CStone

Veteran Member
Joined
Apr 12, 2006
Location
East TN
TDI
2003 Jetta ALH 5sp.
Hmm. I use Mobil Delvac 1 in all my diesels ('03 Jetta ALH, 7.3 Powerstroke, and Kubota mower). 10k mile intervals, except for the mower of course.

After the Jetta timing belt broke prematurely last year, I disassembled the top end looking for damage and was utterly shocked at how clean it was at 155k miles.
 

Drivbiwire

Zehntes Jahr der Veteran
Joined
Oct 13, 1998
Location
Boise, Idaho
TDI
2013 Passat TDI, Newmar Ventana 8.3L ISC 3945, 2016 E250 BT, 2000 Jetta TDI
Lets run the oils out to 30,000 miles and see which one holds up best, The Group III Rotella or the Group IV Mobil 1, any takers?

I already run our MB's out to nearly 20K on the Mobil 1 ESP 5w40 Formula M, wear rates are virtually NIL at 20K. Would I do this using a Group III oil like Rotella in a $30,000 engine no chance.

FWIW, the T6 I see as a perfect oil for use in the PD, VE engines and running 15K 2 year oil change intervals. Pushing it out past 15K I'd have to see some wear trends to insure the margins exist like they have been proven in the Mobil 1 5w40's.
 
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FXDL

Veteran Member
Joined
Oct 27, 2009
Location
Barrie Ontario Canada
TDI
2015 Jetta TDI with DSG
Drivbiwire seems to me by your post above the Shell T6 is a group 3 oil, correct?, So the Shell Rotella T 6 a group 3 oil and not a group 4 oil??? The mobil TDT is a G-4 oil??
 

Bob_Fout

Oil Wanker
Joined
Sep 5, 2004
Location
Indiana
TDI
2003 Jetta - Alaska Green (sold) / 2015 GTI 2.0T
Group 3 vs. 4 and 5 is a non-issue now, and makes no difference except in EXTREME conditions. Most Euro oils are Group 3 and have been for a while. Old school experience with G3 oil has been superseded.

T6 is Group III+. TDT, like all of Mobil's oils, is an unknown. (based on Mobil's PDFs we can guess M1 0w40 is a mix of 3, 4 and 5 though).

BITOG (Bob Is The Oil Guy) has all the info and more one could want on the subject.
 

Drivbiwire

Zehntes Jahr der Veteran
Joined
Oct 13, 1998
Location
Boise, Idaho
TDI
2013 Passat TDI, Newmar Ventana 8.3L ISC 3945, 2016 E250 BT, 2000 Jetta TDI
Drivbiwire Is Rotella T6 is a group 3 oil or a 4? If a 3 will not be my choice.
Shell is and always has been Group III, Shell does not have Group IV production capability.

Mobil is and always has been the leader in Group IV/V technology producing the majority of their base stock oils from Natural gas sources. They provide multiple other oil companies including Amsoil their base stocks leaving the additive packages and packaging to the 2nd tier supplier.

Mobil got into a lawsuit over calling hydro-processed conventional oil a "Synthetic", Shell, Castrol all benefited from this re-naming of a highly processed and "modified" conventional oil as a "Synthetic". Castrol won and Shell jumped on the bandwagon with their branded "Synthetic" 5w40.

As I said before, run the two oils over an extended drain interval and compare the changes in viscosity and wear trends.

As I said before, I'm not going to trade $20 in savings over an oil change interval for maximum protection of my engines. The Mobil 1 5w40 ESP Formula M continues to be my favorite diesel engine oil for all applications be it VW, MB, CAT, BMW of all years and models.

Again, just my opinion.
 
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Bob_Fout

Oil Wanker
Joined
Sep 5, 2004
Location
Indiana
TDI
2003 Jetta - Alaska Green (sold) / 2015 GTI 2.0T
Keep in mind those of you comparing oils what EXACTLY you can glean from a standard UOA. Comparing wear across different oils? Not one of them.

UOAs are best used to determine viscosity changes, oil contamination, additive life, and TBN, things that determine oil life. EDIT: Soot and fuel dilution too.

http://www.bobistheoilguy.com/used-oil-analysis/
 
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Drivbiwire

Zehntes Jahr der Veteran
Joined
Oct 13, 1998
Location
Boise, Idaho
TDI
2013 Passat TDI, Newmar Ventana 8.3L ISC 3945, 2016 E250 BT, 2000 Jetta TDI
in regards to oil analysis....DRUM ROLL........OXIDATION AND NITRATION

Both are direct indicators of the oils break down. Also for systems utilizing oil condition sensors (MB, BMW etc) the engines ECU can monitor directly the oils condition by reading the oxidation characteristic which can be read via a capacitance check of the oil.

The oil condition sensor consists of two cylinder capacitors arranged one above the other. The engine oil quality is
measured by the lower, smaller capacitor.
Two metal tubes are arranged one inside the other as capacitor electrodes. The engine oil is located between the
electrodes as an electrical non-conductor (insulator). The electrical material property of the engine oil changes with
increasing wear and dissipation of the oil additive. The changed electrical material properties of the engine oil
change the capacitance of the capacitor. This capacitance value is processed in the integrated electronic evaluation
unit into a digital signal. The digital sensor signal is passed on as an indication of the engine oil quality to the digital
engine electronics (DME). This actual value is processed in the DME to calculate the next engine oil service.
The oil level is determined in the top of the sensor. This part of the sensor is located at the height of the oil level in
the oil pan. As the oil level falls, the capacitance of the capacitor falls accordingly. This capacitance value is
processed by the electronic evaluation unit into a digital signal and also sent to the DME.
A temperature sensor has been fitted to the electronic evaluation unit to measure the engine oil temperature.
The oil level, engine oil temperature and engine oil quality are measured continuously from ignition ON.
Oil analysis remains a very good indicator to spot a trend, this is the whole point of an oil analysis to determine wear trends and overall condition of the oil.

When digesting a samples data, you need to take into account a particular engines wear characteristics and specific metal components of the sample that stand out from other engines. For a VW, Copper, Nickel, Iron and Aluminum distinguish a VW engine from other engine types due to the design and makeup of the internal bearing surfaces.

If you suspect a condition where damage is suspect, Ferrorgraphy remains the best option to identify the exact nature of the problem by analyzing the specific nature of the process that removed the metals. Also this remains the only method to analyze the particles greater than 4 microns in size which Spectronalysis cannot detect.
 
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