Don’t use STP/Autozone gear oil....Pics attached

[FXtrader]

Hey all - long time intermittent reader of this site but never signed up until today and for a special reason. I picked up 2 gallons of STP/autozone 75w90 gl5 gear oil from Autozone for my 2011 Tacoma diffs and transfer case. I put one gallon in the rear diff and right away I noticed it was very clear and looked like a honey color. I said to myself this was real cheap gear oil $15/gallon and I've seen cheapie motor oil look the same so chalked it up to that. I bought this to put in my truck after draining the very overdue current oil (probably oem) and drive for a week or two to rinse out the old stuff and then drain and fill with Amsoil. I didn't want quality mixing with any old old oil.

Anyways I open the second gallon of the same STP oil to put in the other diff and the color is TOTALLY different (how gear oil should look). Consistency even seemed different (thinner than the first gallon). SAME oil, same part number except the honey-looking oil had a lower serial number on the bottle, the bottle/decal was slightly faded compared to the other gallon which was obviously newer and that one had a higher serial number on the bottle. Also one has the clear oil level sight on the side and the other doesn't (newer one doesn't).

What is going on here? I know STP isn't exactly a top of the line brand anymore but I don't think it's just an older formulation - could they have bottled the oil without adding in the additives? And the honey-oil is the base oil without additives yet? - just a guess. I will be contacting STP about this but worried about driving my truck with this cheap honey-looking oil even if only a few miles a day. The honey-oil is only in the rear diff not in everything so I'll be changing it sooner than expected but what do you guys think happened? Besides poor quality control? Even if the bottle is old and was sitting by the window to fade the label the oil still shouldn't change color - afterall it's made for hotter temps.

 

[bullwinkle]

It would be interesting to do UOA on those two-that one on the left doesn't look like gear oil at all, looks like motor oil!

 

[RamFan]

This'll be good!

Are you able to decipher production code to indicate when the two jugs were bottled?

 

[RooflessVW]

The "honey oil" looks like the last 4 gears oils I have used - Mobil Delvac 75W-90, Mobil 1 75W-90, Castrol Syntrax 75W-90, and Liqui Moly 75W-90.

If anything they were lighter and more yellow-gold.

 

[tcp71]

did you shake the light colored one?

 

[92saturnsl2]

STP probably changed suppliers at some point, and the two bottles you've bought just happened to be on each side of the changeover. That'd be my guess.

Take a good whiff of the honey colored stuff, then do the same with the darker one. Gear oil has an unmistakable smell, it should be immediately apparent if one or the other is not gear oil, or if you've got some kind of neutral oil without additives on your hands.

That said, the whole idea of buying a product that is not consistent is disconcerting. I think I'll avoid STP stuff in the future!

 

[92saturnsl2]

I went and took a close look at the color of the gear oil I have. I have two bottles of Supertech 75w-90 semi-syn, one has the old ST label, the other the newer style. Both have identical color and fall roughly in the middle of the two colors you have pictured. I could see how both yours could be gear oil, but evidently not the same stuff.

 

[Oildudeny]

If both bottles don't have the same batch date and code there's no fair comparison. Could be different suppliers

 

[Doc8404]

did you email the lot/date codes to STP?

 

[StevieC]

I wonder if someone bought it and put something cheaper back in the bottle like motor oil and returned it on one of the bottles. Has happened to me with M1 motor oil before at Walmart, someone had put used engine oil in the one and glued the foil back down.

Also

to BITOG!

 

[SatinSilver]

Originally Posted by StevieC
I wonder if someone bought it and put something cheaper back in the bottle like motor oil and returned it on one of the bottles. Has happened to me with M1 motor oil before at Walmart, someone had put used engine oil in the one and glued the foil back down.

Also

to BITOG!


Same here but with some Castrol Edge EP 10w30. I was furious and let Walmart know about it. Shortly after that happened I hear WM doesn't accept returns on oil any longer. Which is fine with me.

 

[StevieC]

Sad world eh?

 

[FXtrader]

I didn't shake any bottle and I will be emailing STP tonight about it and include the bottle codes. I'm curious what the differences in the 2 bottles really are

 

[Chris142]

Do they smell like gear oil?

 

[bubbatime]

Bottled by two different lube manufacturers. Not an indication of a problem. Over reaction post of the the week!

 

[MolaKule]

Originally Posted by bullwinkle
It would be interesting to do UOA on those two-that one on the left doesn't look like gear oil at all, looks like motor oil!



It would be better to do a VOA from both containers, then we could determine if one or the other or both have Gear Oil signatures..

Formulation changes recently have gone from a high-sulfur/Phosphorus EP package to a Mulit-Functional Phosphorus package with clearer fluids as the result.

I think it would have been more appropriate if the OP had stated a "Caution" than to say "Don't use it" since the jury is still out on the what caused the difference in fluid appearance.

 

[Hall]

I used some Lucas heavy-duty 80W-90 gear oil recently and it was amber color as well. Was I concerned ? Nope, not at all. Their tech sheet says it's supposed to be that color anyway....

The SDS for Autozone-brand 80W-90 gear oil says the color is "Light amber". For STP-branded 80W-90, it's "Dark brown".

 

[parshisa]

Where have you heared walmart is not accepting oil returns?

 

[Donald]

I would have bought Supertech for the purpose you are using the gear oil for.

 

[Leo99]

Gear oil stinks. It really smells bad. Smell the two and see if they smell the same. Feel them. Gear oil doesn't feel like motor oil. It's slimey.

I'd guess the dark one isn't gear oil but I'd do the smell and feel test and see what's up.