Mobil 1 5W-40 TDT, 5.4k, 2003 Saab 9-5 Aero

[greenjp]

Here's the latest report on my 2003 Saab 9-5 Aero. This was a 5,400 mile run of SM Mobil 1 5W-40 TDT with a PureOne filter. The car had 148,100 at the time of the drain. Took 1.25 quarts of makeup oil in 1/4 qt increments throughout the OCI. Previous UOAs at 14k , 45k , 70k , 85k , and 127k.

Code:




Fe 9

Cu 7

Sn 0

Pb 2

Cr 1

Ni 0

Al 0

Ti 0

Ag 0

Ca 1024

Mg 717

Zn 1137

Ph 741

Ba 0

Mo 2

Sb 0

Si 6

Na 11

Bo 27

K 0

Va 0



V40C 80.2

C100C 12.7

TBN 2.2

TAN 3.15

Flash 370

oxid 36

nit 14

kf 569

fuel 0.722

VI 158


Lowest wear yet (though maybe skewed downward due to makeup oil) with a dramatic improvement in flash point and fuel dilution.

jeff

 

[addyguy]

I'm REALLY suprised that with the top-off, TBN is still super low for 5.4k. TDT is supposed to be one of Mobil's strongest oils....

 

[dparm]

Just curious, what's it spec'd for? I think Mobil 1 0w40 would be another stellar choice for this car.

 

[greenjp]

The car was originally spec'd for a 5W-30 semi-synthetic and OCIs up to 10k. This contributed to sludge issues and they've since revised the policy to recommend full synthetic at 5k. I've been doing 5k full syn changes since it was new.

The owner's manual spec's a range of viscosities depending on temperature. Mobil 1 0W-40 is a popular choice but I've settled on the TDT as it seems to perform very well. I believe it has a higher HTHS rating than the 0W which I think is important for a high boost turbo engine. Also don't see too much benefit of a 0W in my climate.

jeff

 

[MI_Roger]

I also run 5W/40 in my Saab 2.3 litre. Usually Total brand full synthetic but currently has Mobil-1 TDT&SUV blend in the crankcase.

These engines are HARD on oil. My TBN dropped form 8.8 to 2.4 after 5300 miles with my 295,000 mile oil change. Lots of anti-wear materials remaining, and everything else within specification, but the TBN shows that extended oil change intervals will become trouble with this engine.

 

[greenjp]

Right, I believe that while things are still fine at 5k, given the TBN, TAN, oxidation, etc they will quickly start going south such that extending much beyond is not advisable.

Funny how the car tells me it's "Time for Service" every 9k or so

jeff

 

[webfors]

TDT is a good oil. TBN is getting down there though... stick with that interval.