If you look up the parts on a Toyota site you will see some of the brackets fit 03-14 and others 03-09. It does look like the running boards themselves are different for 03/04 but I bet they'd still work seeing the brackets are the same, probably just look slightly different.
My limited came with running boards although someone removed them before I got it. I put others I bought on it. Not sure if all models have the holes but you could look. There's 3 brackets per side and each have two bolt holes for bolting onto the angled part of the underside of the floor. Pretty easy to spot.
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Mike
03 4runner Limited
1GR-FE V6 w/199k miles
Last edited by MikeinNH67; 09-12-2023 at 04:44 PM.
I believe the side frames for the 03-23 are all similar. The body on top of the frame varies and so something designed for a 5th gen may be a little longer than a 4th gen.
As long as you have all the hardware - any 4th gen parts should go right in. With a little bit of creativity, you should be able to use 5th gen steps, rails too
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2008 SR5 4WD Black. Bilstein 5100, 5th gen coils/ rear springs. 255 80 17 AT for everyday use. Victory Sliders. Victory Front bumper with winch/ lightbar. headunit upgrade. Back up camera install. Expert at replacement rear hatches
All you need to go off road is to be willing to get some scrapes and dents along the way