STP Gear Oil Treatment

[cwilliamsws6]

Found this in the garage at our new house, took the cap off and the tube is still sealed, unopened.

Could anybody tell me approximately when it's from and if it's safe to use today? Looks like it's just a zinc additive.

My Pathfinder is due for transfer case oil and rear diff oil change so I wanted to know if I could give this stuff a try.

See attached images.

 

[kneesahn]

Cool find.

 

[MolaKule]

Unless you know a product's chemistry and viscosity (which we don't) it's a crapshoot so I would not use it.

 

[cwilliamsws6]

It's a 6 oz tube so I was thinking 3 oz in the rear diff and 3 oz in the t case wouldn't hurt anything being such a small amount.

I don't know if it's an OCD thing but I just feel weird about letting things be unused or go to waste.

 

[Malo83]

Use it.

 

[BMW Dom]

Throw it back on the shelf for another 10 yrs

 

[RyanY]

Apparently it's still available in Europe.

Oil Treatment for Gearboxes | STP®

STP® Oil Treatment for Gearboxes can help keep your gear changes smooth and reduce noise and friction. Read more about its benefits here

www.stp.eu

 

[cwilliamsws6]

I don't think I'll end up using it.

But I would like to find out more information about it for sure.

 

[Warstud]

Could anybody tell me approximately when it's from and if it's safe to use today?

STP + 25 cents + Old = Not Safe

 

[c502cid]

I'd add it to one of my beater cars all day long. Modern stuff probably not.

 

[jrvn]

25 CENTS

 

[zeky]

More sulfur always good. No?

 

[cwilliamsws6]

I cut the end off the tube and squeezed a little out, it's yellowish-clear and it doesnt really smell like anything honestly. Pretty thin too, about same consistency as gear oil is. Picture attached.

 

[cwilliamsws6]

I don't think I'll use it anyways but based on what it looks like in the last picture what do you guys think of it?

 

[zeky]

Did you shake it up first? Looks like it has separated.

 

[cwilliamsws6]

Did you shake it up first? Looks like it has separated.

I spent a good couple minutes shaking the tube and squeezing it around to make sure it was mixed. It might be the angle I took the picture but to the eye it looks one single color, an off-yellow clearish color. Edit: and like I said before it doesn't really smell like anything

 

[zeky]

Squeeze it all out into a container to see it it has seperated

 

[cwilliamsws6]

I shook it up and squeezed it out into a paper cup because that's all I had around. Coming out of the tube the color didn't visually change as it came out and in the cup here is the appearance. Still relatively odorless and viscosity isn't too thick.

Safe to go ahead and use, or dump into my used oil bucket and use this as a fun learning experience?

 

[cwilliamsws6]

In theory, if I were to use it after all, my plan was to pour it into the quart bottle of gear oil and mix it together as a whole so it's evenly distributed between the transfer case and rear differential.

Given the appearance of it now that it's mixed back together and visible what do you guys think?

 

[skyactiv]

Mix it with the used oil for proper disposal. That product dates back between 1986-1999 when First Brands owned STP.
It was likely old stock when Big Lots bought it.

It would have a web address if it is millennial when everyone proudly put that on the back label. So I'm guessing it's from the mid 90's.

Being it's age, I'm guessing the base oil used is a group 1. The product was made when there were more smaller refineries in the USA and I'm guessing STP chose the low bidder.

I'm betting the low bidder base oil has contaminants that would show up in a VOA. The only thing that product will do is detract from the overall life of whatever it's added to.