Geoffrey

It seems that Mobil has reintroduced their old Mobil 1 oil (prior to extended performance version) in a new formula. Below is taken from their website

Website Link to Mobil 1

"Why are you reintroducing Mobil 1 15W-50?*Have there been any changes to the formulation, or is it identical to the previous product?"

Mobil 1 15W-50 is being reintroduced based on popular demand.*Mobil 1 15W-50 provides higher viscosity, designed to provide extra protection for performance vehicles and vehicles that operate in severe service, such as towing, hauling and racing.*Additionally, Mobil 1 15W-50 contains higher levels of anti-wear (ZDDP or Zinc DialkylDithioPhosphate) that may be required for certain racing applications and camshaft designs.*This is a new Mobil 1 15W-50 formulation and is not the same as the product that was marketed a few years ago.

Mobil 1 15W-50 is also recommended for older valve train designs that may benefit from a higher level of anti-wear normally not required for newer generation vehicles.*Mobil 1 15W-50 will also provide better anti-wear protection for higher valve spring tensions in certain racing engines.

smlporsche

So will they be offering the extended performance version as well as this new/old formulation or just this new/old version??

schwank

Fug... so which version do I want now?

Geoffrey

Extended performance is still being offered and is a different formula that the "new" "old" Mobil 1 formula. Both are available in multiple viscosities. You want the Mobil 1 version, not the Mobil 1 Extended Performance version.

LVDell

Uh-oh. Here we go again with the ever popular oil debate

chrisp

This is hard to follow. I know they have had some changes in the marketing side of their division so perhaps this is new blood trying to stake their claim. What's interesting is they claim higher ZDDP but it's still an SM rated oil. The SM standard reduces Zn and P levels because they harm catalytic converters. So perhaps this "new" formulation has higher levels than the previous iteration but not as high as the SL rated version of M1. I am using 10-40 Mobil 1 High Mileage because it's SL rated and I am experimenting with viscosities. You don't want it any thicker than it needs to be to get acceptable oil pressure. Too thick saps horsepower, increases friction, and reduces cooling capabilities. For example, I used 5-30 at my last track day where it was about 70 degrees and I had excellent pressure. My temp gauge read 180-190 all day (stock 3.0 with a small-ish front mounted cooler)

Larry Herman

I gave up on Mobil 1 and went back to Amsoil. I ran that stuff 25 years ago in my 914 2.0 which used to cook conventional motor oil. Never had a problem or temp/wear related issue in 6 seasons of tracking that car.

ltc

If I understand it correctly, Mobil 1 15W-50 Red Top is back, just not the exact formulation of the 'old' 15W-50 red top. ZDDP levels, more modern API rating issues, etc.

I still have ~ 50 gallons of the 'old' Mobil 1 15W-50 red top in 5 gallon jugs (cleaned out Wally World), so I figure by the time I've gone thru it, I'll have figured out exactly what is going on with M1 15W-50.

chrisp

Gallons or quarts?

Oil has a shelf life. I am no expert but from the settling I have seen in 18-24 month old bottles I would say use it up in the next 2 yrs.

ltc

Gallons...like I said, I bought out the local Wally Worlds before the stopped making the 'old' red top 15W-50.

I was unaware that (unopened) synthetic oils had a shelf life. Thank you.

sjanes

When Mobil1 changed the 15-50 to the new API SM spec, I switched to their V-twin 20-50 synthetic motorcycle oil as it still contains high levels of Zn and P anti-wear additives.

daigo

OK, is it the "New Coke" or the "Classic Coke"

hacker-pschorr

I see a product data sheet for almost everything on the Mobile site - except the "new" (old) 15w-50 discussed here.

Has anyone found the data sheet to do a side by side with the other 15w50?

multi21

Can someone confirm or deny that synthetic oil has a shelf life and if so, what is it?

Dan V

http://www.mobiloil.com/USA-English/..._Warranty.aspx