1976 Ford Gran Torino, 351M engine, hasn't seen regular driving in at least 15 months. Engine has been started every 2-3 months and no oil has been changed in this time. It's black, it's full, and the car smokes a little blue-gray on startup, goes away by the time the t-stat opens. I have repaired a few things on the car needed to pass inspection and I'm about two weeks away from taking it in for that safety inspection. I want to change the oil before I install the new battery and cables and have it ready to run. Motorcraft FL-1A filter is a must. Whatever oil I put in will only run about 500 miles but I want something that will help clean the engine out while protecting it. It does have a bit of valve clatter (probably from fuel dilution as I have to prime the carb to start it when it's sat for more than a month but it will restart fine on its own after the first good 5min idle). I'd like to go with MCSB, as it is cheap, Ford branded, and readily available even at my awful local Wal-Mart which is 2/3 the size of the average Wal-Mart and the employees have 1/3 the common sense.* Are there other weights that would be more appropriate? The owner's manual for a 1975 Torino (which is the only one I have) claims that during weather -10F to 90F and above, 10W40 should be used. If the temps don't get over 90F (this is Texas, it's already pushing 90) then use 10W30, and if temps regularly drop below -10F, to use 5W30. So I suppose 10W40 is the way to go, do they even make a MCSB in 10W40? *I reset the chips aisle last week and they KNEW a reset was coming, but they restocked the entire aisle to capacity within hours before my crew arrived to reset the aisle...which means a 4 hour job became 7 hours. They told us they knew we were coming but they forgot. DUH!