2004 Mercury Grand Marquis LS 12k miles
I just Got a 04 Marquis. The original owner passed recently. He Bought the car new because he thought 04 would be the last rear wheel drive Marquis. He was wrong but that’s not the point. The car was garage kept and is mint. It even has original tires. My question is what fluids go bad over time and should be changed? Oil obviously. But what about tranny, break, coolant, etc. Thanks for the advise.
At that age and mileage I would renew all of the fluids and certainly get new tires. (Check trans fluid for condition first to be on the safe side.) Don't be surprised if seals start leaking on that car due to age and lack of use.
Thanks! Any specific seals to keep an eye on?
Brake seals, engine seals, transmission seals, power steering seals. Age takes its toll. Lack of use means oil seals are not getting much lubrication. If brake fluid has not been changed in 20 years and the car has mostly sat unused moisture can cause corrosion which tears up brake seals.
It even has original tires.
I would think (and hope) that would be one of the first items on your list!

Fortunately all the seals are good the car was driven almost weekly. New tires go on in 2 days. Thanks for your advice