This option is no longer available. It was removed from the Payroll menu because it relied on an older data source that current payroll deductions no longer use. It was a custom export that had to be modified for each pension plan's reporting requirements.
Pension plan administrators now generally accept uploads through their own websites, and their formats differ. Contact ACS if you need a pension or 401(k) contribution file; Pension Report and Payroll Registers can list the amounts to report.