Re: Oversized baggage PIA
oh good, don’t worry about packing then! 
the airlines’ baggage dimension restrictions are mentioned on all of their websites under 'Free Baggage Allowance" … you scroll further down and you will see the dimensions for maximum baggage sizes.
there is no charge if their weight is under the weight restrictions…with most airlines, to and from US/Canada, it’s 23 kg for each of the two bags. these bags can weigh up to a maximum of 32 kg for an additional fee of $50. anything above 32 kg and/or over sized, you have to pay extra/kg charges and book through the “oversize baggage handling”.
the charges for extra baggage to and from the US is around $200
you should check with your airline.