QUOTE(76-914 @ May 23 2016, 11:26 AM)
Crap! OK, now tell us why it came loose so we can avoid a similar situation. Also, was there any collateral damage?
No damage. I have a redtop optima and i've been using their plastic holddown for years. It felt tight before the run and i did pass tech inspection (the guy did check the battery and it didn't move).
It looks like that the mounting hole for the holddown is about 2mm off and the rounded edge doesn't sit flush against the battery.
So all that is preventing it from moving is the clamping force between the front of the holddown and the battery base which apparently wasn't enough.
Once the battery moves even just 2mm, it'll slide out of the back channel and is free to go wherever it wants to go.