You from SoCal?
Northern California, never heard it before.
Can you give that to us in IPA? 
Given that Asimovian actually used the slang growing up in SoCal, I think it’s ok believe it’s “real”.
Oh, I jumped when I should have hesitated. I voted that I’d heard it, though in another context.
But i read it as “Modded”, being short for “modified”. I’ve heard that frequently in the performance car/bike/engine world.
Northern California (SF Bay Area) and I remember the term from the 80s in elementary school.
South Bay - Torrance to be exact.
I thought of that when I typed it, and then I thought, “Nah, no one’s gonna be that anal about this, right?” 
I remember it being used in my elementary school days in California in the 80s, but I’m not entirely sure that “moded” is the right word for it. It sounds like what people said, but I don’t think it’s quite right. I’m almost positive it’s derived from a mental illness or handicap or something, like the way “tard” was pulled out of “retarded.” I just can’t remember what the source word would have been. Demoted doesn’t seem right.
You left out an option.
I AM from California - LA specifically (Go Redondo!) - and grew up in the late 70s/early 80s - therefore in your sweet spot - and never heard the term. It rings no bells at all for me.
Hell, maybe it’s from the valley or something. Redondo is beaches. Whole different world.
Yo, homes!
Huh. Well, I don’t think most of the people at my elementary school had sniffed much of the valley (literally or figuratively) at that point, but who knows? I’m going to consider you an outlier until I hear otherwise. 
http://uncyclopedia.wikia.com/wiki/'Moded
I was curious and found this by googling. Uncyclopedia spells it with a leading apostrophe.
Yeah, but that looks - from the phrasing surrounding it - to be more very late 80s and early 90s than earlier.
When are we talking here. I seem to recall LA slang evolving extremely rapidly at the time - possibly always, there’s no real way to define what growing up in LA is like to people who didn’t - so if I were in junior high in 1978-1981 and high school after I might be a different slang cohort than you, Asimovian. If you were in elementary school, at least.
I was at the school where I remember using it from 1984-1988.
Someone else suggested to me that the term might have started as slang in black culture that ultimately gained wider usage. My elementary school was private and had kids of a number of different races, so I don’t really have any insight into whether that idea has merit.
That’s definitely what I remember from elementary school a little later than that. In fact, I was pretty much positive people would invent words, pretend they were in common usage and make fun of you if you didn’t know it. Everyone else scrambled to make sure they were using the word, so that they wouldn’t be made fun of.
Yeah, so it may be a matter of cohorts and specific regions. LA’s enormous, after all. I’m certain my group never used it. My schools were largely white with some latino. You both being younger and from a different region might explain it.
Duuuuuuuuude!
And I was on the border of Torrance and Redondo and definitely heard it on the beach.
As I recall, we didn’t say “you just got moded”, it was more like just " whoa, moded" and meant, basically, “what a burn!”
Sometimes I get so homesick after reading stuff here 
Possibly. My school was just outside of DTLA, and I grew up on the border of [del]South Central[/del] South LA.