Originally Posted by benhen77
If you're going to buy spare parts, you may as well just install the new parts you buy right away and hold on to old worn (but still working) parts in your trunk for emergencies. 1) you'll reduce your likelihood of breaking down in the first place. 2) new stuff sitting in your trunk will continue to age that part. Belts and electronic components can go bad just sitting.
Fuses and fluids are as far as I would go.
That. If I feel a part is starting to go bad (like a pulley, alternator, etc.) I replace it, and keep the old. Well pulley and alternator no, but coils, sensors, etc.
On the Barchetta I gradually replaced all sensors, a few died of old age and since I was there I replaced them all (not a lot on this car), kept the old mostly for # reference, or to give to another Barchetta owner at the club, when in need at a meeting.
If I look in my sig I have spark plugs for the Barchetta (copper) and the Colt. Air, cabin and oil filter for all, fuel filter for Barchetta, a generic stash of fuses and relay (that I never had to replace in like 15 years BTW). Belt for Barchetta and Colt, the Mazda got the new belt/tensioner/pulley in advance since I felt like changing them.
In each car I have like a litre or two of oil just in case, transmission fluid in the automatic for the same reason. Never used that for me but often gave to someone in need.
In the garage...well many jugs of oil, manual transmission oil, but just 6 litres of transmission fluid, since the Mazda is the only automatic and takes the "stupid" Mazda MV fluid. Don't forget some spare rags, brake/parts cleaner, WD40 or equivalent, anti-seize, and a few sorts of grease (basically all what a basic garage would have).
Also I keep a few generic tools in the cars, something to change a tire more comfortably than the factory mini tool, x-acto knife, clamps, a few screwdrivers, wrenches for oil change, battery replacement, and a flashlight.
I try to do all maintenance preventively, and rarely got stranded on the road. Once a fuel leak, once a damper pulley that lost a part and took the serpentine belt with it. Everything else that happened I managed to go home. Maybe I shouldn't keep all that stuff in my cars... My father used to have a lot of parts in his trunk, even a spare plastic windshield in case his were to brake.