Since the CTS 3.6 requires Mobil 1, and the oil change intervals are about 6/7 months or 7 to 8,000 miles.. (according to the service advisor) was wondering if I change the filter @ the 1/2 mark, would it help prolong the life of the oil. Filters are a lot cheaper than the oil..Thanks
Barry/Austin

 

Look at it this way. We change dino oil about every 3k miles. You go 2 1/2 times further on synthetic.

I don't know if you would be able to go comfortably that much further with just the filter change, because the filter has nothing to do with the oil maintaining it's viscosity.

Check out this link, I don't know if it will answer your question directly but I found it to be interesting.

Synthetic Oil Life Study

Bottom line, oil really isn't that expensive for the job it performs.

Hope this helps somewhat.

 

Thanks for the info.......However, you never answered my ?..
Thanks anyway...
Barry

 

in the old days, GM required oil filters every other oil change.
the job of the filter is to remove solids/impurities ... period.

the oil additives simply break down with use, heat & abuse, moisture, and misc
variables & issues. oil changes color & the additives are used up due to these issues,
filter or no filter. even the oil in the kitchen frying pan will do that.

you can change filters every week and the oil will still fail at the same point.
filters do NOT add basic life to the oil in the crankcase.

not sure that i agree with the old 3,000 mentality, but that is another subject, and it
certainly will not hurt the car to do that.

however, many cars go 10,000+ miles with standard dino oils and are clocking 200,000+ miles.
do read the FAQ on the OIL monitor algorithm -
it is quite enlightening.

https://www.cadillacforum.com/m_5792/tm.htm





.

 

BTW, i know a few racers and they make it a habit of changing engine oil, trani fluid, and axle gearbox
fluids after a day of racing with only a few miles .. somehow, that makes sense to me. after all, the engine
components, gears, and clutches have been put to high stress.

i do try to change all-axles gear fluids after running the 4x4 in sand and/or in water, after it gets a good
undercarriage water blasting. it always gets the water blasting, the fluids change, is a little more challenging.
key word here is "try".