any thoughts on an additive called Polydyn TX7 engine treatment. Jiffy lube claims it improves gas mileage and engine life.
I’ve never heard of it but I can safely bet that it’s just another item in a long list of scams.
If it claims something along the line of “penetrates the metal, fills the pores, reduces friction, yada, yada, yada” then it’s not a safe bet; it’s a sure bet. 
I think ok4550 means a sure bet to be a scam.
what improves gas mileage and prolongs engine life is the regular oil changes, and periodic maintenance you should do regularly on your car.
your car is NOT able to somehow wonderously turn into a hybrid and have exceptional mileage. if you do regular oil and filter changes and tire checks on your car you will keep the mileage up that it is capable of.
these miracle cures are only going to extend and increase profits for these stores that sell them.
Polydyn TX7 appears to be another teflon formulation similar to Slick 50, which is in trouble once again with the FTC. See “Quaker State Ads For Slick 50 Are False And Midleading, FTC CHARGES” at
http://www.ftc.gov/opa/1996/07/slick.shtm.
If something is “able to soak into the metal”, what keeps it from soaking through the oil pan at night and leaving a mess on the garage floor? ;-}
Your first mistake was to entrust your car to Jiffy Lube, as a competent employee is extremely rare at that chain operation and an untrained person can easily mistake the oil drain plug on a Subaru (or even on a “Suburu”!) for the transmission drain plug, as they are very close together and are identical in appearance. Many Subarus have had engines and/or transmissions ruined by untrained technicians, and the people at Jiffy Lube don’t have the expertise to do anything even remotely technical or outside of a very small list of rote tasks.
Your second mistake would be if you were to believe the bogus claims that were uttered by one of these untrained Jiffy Lube employees. If you return there, then…well, I won’t comment any further on that topic except to suggest that you do some Google research on phrases such as “Jiffy Lube ruined my engine”, or variations on that theme. Maybe then you will believe me and will avoid that place.
What the heck are you doing at a quick lube place? Keep away from the quick change places. We hear far too many horror stories about them. Some may be fine, but many pay the help little, demand fast changes and that results in a high percentage of errors. Too many live by selling you something you don’t need at inflated prices.
Find a good local mechanic and stick with them for your needs.
Don't go to the quick lube places, even for directions.If you do own a Subaru, you really don’t want to take such chances at Jiffy Lube. The additive will work or not work the same as the one you can buy at whatevermart or auto parts store. Nothing that you pour into a car will save the car from oil that doesn’t get put in, a drain plug that falls out or a loose oil filter.
A number of racing teams use it apparently. It probably won’t do you too much good on the street, however. Your car just isn’t driven as hard as the racers. I would avoid it for a personal car. BTW, the J-Lube you go to may or may not be any good. I use one near my home and have for ten or more years. The owner is a franchisee and they do good work. There certainly are bad ones out there, but there are cheats in any business.