If a supposedly reputable oil change franchise failed to drain out the old oil, resulting in engine failure, is the franchise financially responsible?

If the negligence of a Jiffy Lube' franchise caused your friend damages, she would have a civil claim against that franchise.   She might be able to concoct something against the franchisor, but, unless her contract was with the franchisor itself, the claim would be very weak and probably not worth pursuing.  Moreover, any claim she might have against the franchisee would be affected by the provisions of her contract, which might very well have provisions limiting liability.  For esxample, it might say that any recourse for negligence is limited to return of the amount paid for the services.  Such clauses are enforceable to different degrees in differenct states.  For example, in NY, the clause is enforceable for ismple negligence, but would not preclude recovery of actual damages if the plaintiff could show some culpability beyong simple negligence - gross negligence or intentional wrongdoing, for example.  I don't know what Tennessee law provides, or even if Tennessee law governs, since the contract probides otherwise.  It also may provide for arbitration.  The first step your friend needs to take is to read her contract (or hire a lawyer to read it for her).   P.s. I felt compelled to edit this to add that you will need an expert to testify that the cause of the problem was the failure to drain the used oil.  Your video can be useful for showing the condition of the car, but the part showing the goy from Pep  Boys opining as to what he thought the cause was failure to drain the oil will probalby be considered inadmissible hearsay (hearsay is an out of court statement offered in evidence to prove the truth of what the person said).  He was not under oath when he said it, he was not subject to cross-edxamination, and he had not been qualified as an expert (only experts are allowed to testify to their opinions, as opposed to facts of w hcih they have personal knowledge).