I am aware of the parking and transit deductions available as pre-tax in NY. Does PA have the same option?
Sorry, no idea. Remember that you not only have PA state taxes, but locals as well, all of which can be different.
If God truly hated me and moved my company's nexus into PA, I would get one of the paid payroll library services (APA, BNA, CCH, RIA). Of course I used BNA or CCH when I was working. I was in 43 states at my last job and trying to keep track of state payroll law without a library service was a non-starter.
Some notes on Pennsylvania taxable wages
Do not include Group Term Life Insurance (Basic Life Imputed Income). GTL is NOT taxable in PA.
Gross wages are NOT reduced by pre-tax SIP/401K and SIP catch-up, FSA Dependent
Care, TRIP (parking/transportation).
The following are pre-tax medical, dental and vision deductions.
Hope this helps