Is the difference between public and private pensions only an American problem?

Nope.

Montreal Gazette:

A recent Canadian Federation of Independent Business compensation survey found public-sector employees at the federal level receive 42 per cent more than their private-sector equivalents, 25 per cent more at the provincial level, and 36 per cent in municipalities. Lavish public-sector employee pension and benefits programs drive this giant discrepancy.

James Pierlot wrote in an article for the C.D. Howe Institute that the median retirement age for a public-sector work is 58, while it is 62 for a private-sector worker. The annual retirement pension income for the same public-sector worker will be five to seven times larger than that for the private-sector worker.

It is no surprise, therefore, that there is a growing frustration felt by private-sector workers who must work longer and pay high taxes longer to provide for public- sector workers who work shorter careers and receive significantly better benefits in retirement.

[...]Two thirds of Canadians (67 per cent) don't have any pension plan at all, except for whatever they have stashed in the bank or under their mattresses.