I am pretty sure the "correct" answer is that each brand of forklift and shock monitor systems are approved separately by the manufacturers for each series of forklift.
The real answer is that you have to check with the manufacturer of the forklift to insure that they allow that brand of shock monitor to be installed on their units. most all the major brands will be pleased to provide you with install instructions, programming and wiring directions.

`````just joking below here````````
I know that "Ted's For Clift Attach Mints" 'Tesla&trademark branded Static Shock monitor cap' does not change the forklift's warranty, but it won't tell you if someone hit something, unless it was hard enough to knock the cap off the head of the person wearing it.

as long as you install it according to the installation instructions, no it will not void any warranties.
I install them all the time... fairly easy to do :o)

From our experience the answer is no it should not void warranty