(What can I say? There will be dipsticks and dipshits, so eventually this posting will be at best borderline for kids and the sexually modest.)
News commentator explains that in citing the slogan
You can pay me now, or pay me later. (the pay-me slogan)
the day before, he’d attributed it to the wrong advertiser, adding that the right one was FRAM oil filters. The slogan conveying that you can pay some money now for a good oil filter — or you’ll pay more later when your car breaks down (though of course with wider applicability, conveying at least that you can pay for prevention, or you’ll have to pay more for the remedy).
And then added with a big grin that FRAM was also responsible for the slogan
The dipstick tells the story. (the dipstick slogan)
conveying that you should check the dipstick regularly (and change the oil when it looks dirty) and serving more generally as an exhortation to monitor the state of any important mechanism regularly — in particular, using the sexual slang dipstick ‘penis’, as urging men to check their dicksticks regularly to make sure they’re in working order.
The dipstick slogan came first, 80 years ago. By thirty years into its career, the slang uses of dipstick (for both ‘penis’ and ‘fool, stupid or incompetent person; obnoxious person’) were spreading, so FRAM switched to the pay-me slogan, which is much harder to raunch up (but not impossible, in a world in which high-end prostitutes, of both sexes, accept payment by credit card).
The slogans: history. From Wikipedia:
FRAM is an American brand of automotive replacement parts offering oil filters, air filters, fuel filters, and similar products.
(#1) Early FRAM decal with the dipstick slogan; the earlier separated spelling dip stick has since been replaced, apparently everywhere, by the solid spelling dipstick… FRAM introduced its first slogan, “The Dipstick Tells the Story” in 1942.
(#2) From a commercial with the pay-me sloganFRAM introduced its iconic slogan, “You can pay me now, or pay me later” in 1970.
Keep those dates in mind: dipstick in 1942 (during WW2), pay-me in 1970 (during the Vietnam War and the Counterculture period of roughly 1964-1974 often referred to as The Sixties).
Gentlemen, insert your dipsticks. From Wikipedia:
A dipstick is one of several measurement devices.
… Dipsticks can … be used to measure the quantity of liquid in an otherwise inaccessible space, by inserting and removing the stick and then checking the extent of it covered by the liquid. The most familiar example is the oil level dipstick found on most internal combustion engines.
Such as the FRAM dipstick shown in this 1944 magazine ad, in which dipsticks are mobilized for the war effort by an authority figure presented as an MP (standing for Military Police in the real world, for Motor Protector in the ad world):
(#3) The MP is wielding a dipstick with an oil droplet falling from its business end (all this in the very masculine world of auto mechanics); and then the dipstick slogan at the bottom
Now, some reflections on the V + N compound noun dipstick. First, on the automotive compound and its semantics:
— the compound is subsective, endocentric: a dipstick is a stick
— it is interpreted as V + Object, as ‘stick that you dip into something (for some purpose)’, with the specifics of the thing dipped into and the purpose of the dipping stipulated for different senses of the compound; in the case at hand, the stick is dipped into an automobile engine to test the level of engine oil
The compound then falls in with a collection of other V + Object compounds in English — for example, pull chain (a chain that you pull, to switch electricity on or to flush a toilet; cf. push button); stickpin (a pin that you stick into clothing, specifically ‘(North American) a straight pin with an ornamental head, worn to keep a tie in place or as a brooch’ (NOAD)); call girl (a girl — that is, a female — that you call (by telephone, traditionally) to arrange for her sexual services, ‘a female prostitute who accepts appointments by phone’ (NOAD)). (Note: V + Object compounds are very much a minority option in English morphology.)
Now, on the compound dipstick in all of its senses. From OED3 (Dec. 2021):
… 2. An instrument used to ascertain the capacity or content of a vessel containing liquid; (in later use) esp. a rod used to determine the level or quality of oil in a vehicle’s engine. [1st cite 1824]
3. A strip of paper or plastic containing one or more reagents, which is dipped into a sample of a body fluid or other liquid to test for specific substances such as protein, glucose, etc., the presence and concentration of which are typically indicated by means of a colour change. [1st cite 1960]
4. slang (originally U.S.). A stupid or obnoxious person. Cf. dipshit n. [1st cite 1968 in a slang collection]
5. slang. The penis. [1st cite 1970 in a slang collection]
You can see from appearance of the slang senses in 1968 and 1970 collections — indicating oral usage for some years before — why FRAM might have decided to abandon its dipstick slogan in 1970 and replace it with something less suggestive: the pay-me slogan.
GDoS then provides documentation on the later spread of the slang senses, undoubtedly encouraged via the BBC tv series Only Horses and Fools and the US tv series The Dukes of Hazzard. A photocopy of the entry (the best I could do with the tiny print in GDoS, but I flinched from trying to type the thing out by hand):
(#4)
Finally, the development of automotive dipstick to penile dipstick is a routine metaphorical extension, and the developments from there to ‘fool; incompetent; unpleasant person’ and a generalized insult are routine extensions of words for penis to pejorative uses (with prick and dick as prime examples). But this pejoration of dipstick might have been catalyzed or facilitated by its phonological similarity to (pejorative) dipshit. So, some final (speculative) words on dipshit.
From NOAD, taking things back to pejorative dip:
noun dipshit: vulgar slang, mainly North American a contemptible or inept person. ORIGIN 1960s: perhaps a blend of dippy and shit. [AZ: or a N + N compound of dip and shit]
noun dip: … 6 North American informal a stupid or foolish person. [AZ: might be a clipping of or back-formation from dippy — as noun ditz < adj. ditzy clearly is — or adj. dippy might be an ordinary derivative of noun dip, as in adj. bossy = noun boss + –y, etc.]
adj. dippy: informal stupid; foolish: dippy ideas. ORIGIN early 20th century: of unknown origin.
However, GDoS distinguishes two subsenses of its noun dip-5: 1 (orig. Aus.) (also dippo) a fool [1st cite 1885] … 2 (US campus) a bore, a dullard; something tedious [1st cite 1964 in a slang collection] — in compounds diphead ‘a fool, an unpleasant person’; dipshit; and dipwad ‘(US) a general term of abuse’ [and also, perhaps, dipstick]