New oil, is this just placebo?

[dparm]

The car: 2005 Audi S4, 4.2L 40V V8

Removed the 7-month/5000-mile old Lubro-Moly Synthoil 5w40 and replaced it with Motul 300V 4T Factory Line (also 5w40). I swear, the car felt faster on the drive home. Felt like it was revving much faster.

Placebo? Methinks so.


PS: that stuff is weird, it's bright green like coolant.

 

[Lethal1ty17]

could just be because you changed the oil, regardless of the oil brand.

however i did notice a nice improvement in my car when i switched to castrol edge, but i was going from pennzoil platinum with lucas oil stabilizer to just a straight oil.

 

[dparm]

OLD:

Density @ 15C: 0.85
Visc @ 40C: 87.5
Visc @ 100C: 14.4
VI: 171
TBN: 9.5


NEW:

Density @ 20c: 0.858
Visc @ 40C: 72.7
Visc @ 100C: 13.32
VI: 187
TBN: 8.3


Perhaps the lower viscosity is helping it rev more quickly? Just guessing.

 

[dparm]

You know, the more I think about this, the more I think it's placebo. In theory the oil should get MORE slippery as it wears out so the car would possibly feel "slower" with fresh oil.

 

[demarpaint]

The old oil could have been a little thicker because of age, more drag.

 

[yannis]

Motorbike Engine Oil....

 

[ARCOgraphite]

There is more to oil than viscosity - though that is a major contributer. Some oils have more inherent lubricity and are "slickerier" than others. e.g: Mobil 1 High Mileage 10w30 feels on the road like a much thinner oil than Rotella T 10w30, though they are the same viscosity near the high end of SAE 30. Between the moly and the di-ester base in the 300v - it should be a power making oil. If an oil feels better than an other dont let anyone tell you that YOU cant feel the diff - YOUR satisfaction is the one that counts, right? THEY arent driving the car - YOU are. If you are a pro racer - go with the dyno - though WOT dyno pulls dont show the diff in 1/4 throttle roll-on torque.

 

[sciphi]

I swear I noticed a difference going from a 5w30 Quaker State Torque Power ($14 for 5 quarts on clearance at Wal-Mart, bought 3 jugs) to 10w30 Valvoline MaxLife. The car seems more sluggish, and needs more throttle to move. It's also idling smoother. Filters were the same Advance Auto Total Grip, so it's not the filter. Gas mileage has strangely seemed to go up, though.

If it feels different, or if somebody else notices, then it definitely was the oil. Otherwise, who knows?

 

[Jimmy9190]

My truck was sluggish on Maxlife too. Same with Napa brand HM. It got better with regular 10W30 conventional oil and the MPG improved a little.

I don't think it's placebo effect. Different types and grades of oil can definitely affect how an engine runs. That's one thing I learned here.

 

[Capa]

I recently switched from Mobil 1 Advanced Fuel Economy 0w30 to Mobil EP 5-W30 and my car feels smoother. It is so silky smooth. On the previous oil change when I changed from conventional to AFE I did not notice any difference in smoothness.

 

[dparm]

Yeah, my satisfaction is what counts. Even if it's placebo, I'm totally satisfied with my purchase.

 

[mechtech2]

Thinner oils allow more power, for sure.
How much? Depends. An extreme example is that Nascar cars often use 5W to qualify.
For normal street cars, this is especially felt in smaller engines.

But I often feel an improvement with any oil change, or after washing the car.

 

[Ben99GT]

Different oils have different friction coefficients, some oils can provide better ring seal.

I don't think improvement felt after swapping to that ester based oil is necessarily a placebo effect. I've noticed similar swapping from PP and PU to RL in two different vehicles now. Some SOTP improvement and NVH improvement, and I trust my ears.

 

[Gary Allan]

I agree, at least under some circumstances.

I know you can feel the difference between Bruce's stuff and even something like MC 5w-20. It's not just some "freer revving" deal. The 5w20 and 5w-40 makes the engine feel strained at 3000rpm +. The 0w-10 does not. I can't see it being the viscosity ..otherwise one would reason that there would be some perceivable variance in the condition. It must have been the "stealth polymer" that Bruce added (he still hasn't come clean on what it was). Not that the engine ever had any sewing machine like smoothness to it to begin with.

 

[charbaby]

Every time I wash my car, it seem faster, quieter, smoother and better riding. All of these things deminish as the car gets dirtier. That's when I know I need to wash it again.

 

[CATERHAM]

Originally Posted By: yannis
Motorbike Engine Oil....


Yes, this 4T is motorbike oil!

It may be the placebo effect, but that doesn't mean there isn't less oil drag (friction) with the 300V Motul.

 

[Hokiefyd]

Originally Posted By: mechtech2
An extreme example is that Nascar cars often use 5W to qualify.


If they're qualifying on it, they're racing on it too. Most races are impound races aren't they? In other words, no changes allowed to the engines (including changing the lubricant) between qualifying and racing.

 

[CATERHAM]

We're being just a touch pedantic here.
The phrase "Qualifying oil" is used loosely for short duration qualifying, practice and races where oil temp's don't get above 180F.
Actual Nascar races typically use 20wt oil.

 

[dparm]

Again, my question really is this: can different oils make an engine run noticeably better? (to the point where the drive feels it)

We are talking about moving from one 5w40 to another, not changing off some crazy oil.

 

[CATERHAM]

dparm, there are an awful lot of subjective impressions between motor oils on BITOG.

I can certainly notice the difference between certain oils in terms of an engine's responsiveness with a lighter oil vs a heavier oil. So the answer to your question is yes.