We do it all the time when we visit Costco/Sam's Club or get a great deal from any vendor looking to offload a lot of some product. My question to you is, what have you bought in bulk for your vehicles?
As I love 70-90s Fords, I found myself buying two of these long nylon rods so I can rebuild Ford power window motors (the nylon bits break down over time) any time I want for a tiny fraction of the cost of an aftermarket rebuilt motor. I bought 2 feet of this stuff 15 years ago and used it up last December, so this supply (8 feet) should last me the rest of my life!
AND FOR THE RECORD: I was gonna buy 4 feet but when it doesn't cost any more to ship another rod, why not get a lifetime supply?
*Gasket paper, for the NLA gaskets.
* 90w gear oil. Seems like it’s getting harder to find and because multi viscosity is for young girls.
* Just bought a bag of SAE zerk fittings. It’s getting so that even farm equipment are using metric and one of the 3 chain parts stores near me didn’t have any at all...either that or the younger clerk didn’t know what they were.
One of my sub-goals in life is avoiding shipping charges, so I always buy maintenance items in quantity. I also keep on hand parts that I know will wear out eventually. Our two daily drivers, two collectables, and one that falls in the middle use mostly the same parts. If I do make a special order, I fluff it up with common stuff to get free shipping.
Oil filters - by the dozen My 3 Alfas all take the same cartridge. Foam and terry pads for detailing 24 each. Valve Stem caps - had to but 100 to get a good price. I've used 8 in five years.
No more - I used to get Jeep's oil change deal, (4 in two years) but the time ran out before they were all used and the dealer wouldn't give me a break on a couple weeks. With covid, we didn't do much driving.
My direction - different, some bulk items. At estate and garage sales I watch for unopened qt. oil containers, ditto radiator coolant, windshield wipers still in their bubble packs, WD-40 cans, also yard fertilizer, weed killer -- .
Oil filters - 50515 Wix fit most 60's - 80's Mopar's
Brake line tubing - costs more to ship 1 than buy 10
Brake fittings - difficult to find in one place
Oil - 10w-30 in bulk means never having to run to the store for that 1 extra quart
Fasteners & clips - Why buy a few when you know you will be short for the next project necessitating that annoying run to the store for an overpriced few.
Hoses - keep a variety of sizes for all the reasons above
Spark plugs - getting so standard copper plugs are darn near impossible to find let alone the kid behind the counter not knowing they exist.
...and probably more if I sit here and think of it.
5W30 oil and oil filters
Clips and push pin retainers
carb and brake cleaner by the case
Windshield washer fluid by the case
All my vehicles have K&N air filters so I don't have to buy those anymore
There is probably more that I can't think of right now
Oil,grease, all fluids, zip ties, circlips, cotter pins, any hardware that I have to buy I will buy bulk so that I never have to buy again (usually cheaper than buying the required number), shop rags, light bulbs, fuses and just about any consumable. The only way to keep 4 classics and 2 daily drivers on the road.
VW parts. I seem to buy them in barn loads. I still have a building to clear I bought 3 years ago. Luckily the owner has been understanding. I think all air cool VW owners do this stuff.
Shop rags and Go-Jo hand cleaner, this was a must. My wife got Pi--ed off cleaning my greasy hand print above the pi--er. I also keep plenty multi colored electrical tape, shrink wrap, fuses, convoluted tubing.
Not so much anymore, but Corvair Fan Belts... always were bought 3 or more. It may happen again, 61 Rampside is on my last good spare! Then again, its only thrown one belt in 11 years.