newly acquired '87 monte ss. passenger wiper arm had a lot of movement in it. pulled the arm off and see that the retainer is a bit messed up. the real issue is, why is the wiper arm slot so much bigger than the lever on the car? how in the world is this arm supposed to have a snug fit when they seem totally different. i thought at first maybe i had an incorrect arm, but all the searching i've done shows that this is indeed the factory style wiper arm. any input is great, thanks.
-Shaun
Shaun,
The extra room inside the wiper arm cavity is for fine tuning the position of the arm in the "parked" position.
There are/were splines inside the cavity and on the hub that keep the arm from flopping around.
Unfortunately, after 30ish years and rough handling owners, these splines get damaged and stripped.
Inspect the cavity for the female half of the splines, and the hub for the male half.
If either or both are stripped or missing the splines altogether, the arm will not stay snugly in place.
Only option at that point is to replace the arm and possibly even the hubs for better condition/undamaged ones.
Donovan