The massive gap means mixed news for members of the Imperial Home Decor (IHD) fund, which serves both former Storeys and IHD employees.
About 1,300 current pensioners are guaranteed pensions at current levels BUT with no promise of increases in years to come.
Another 2,500 who are not yet receiving payments will, however, get less than they anticipated.
"Sadly there will have to be some significant scaling down of expected benefits for these 2,500 people," said Giles Orton of Evershed Pension Trustees, who have been examining the fund.
It has assets of over £120 million but would need more than £190 million to meet members' future expectations, according to Mr Orton.
"This is a large deficit relative to the size of the fund," he added.
Legal action would also be needed – probably in the High Court – to establish exactly who takes precedence for available money.
And that could take many months.
The fund has hundreds of members in Lancaster district and more in Darwen. Storeys and its later owners IHD had plants in both areas. Assistance might also be available from a £400 million government scheme. But if assistance was forthcoming, it would not be a major amount.
A trustees' letter tells existing pensioners: "Please feel assured your current pension payment will continue to be paid as normal for the rest of your life with any attached spouse's entitlement thereafter."
That will, however, only be at present levels, unless the legal action changes things.
"This is not the best news possible," said one existing pensioner.
"But it is better than being completely in the dark as we were before."
The IHD scheme was closed to new entrants when the firm was taken over about two years ago and is now being wound down.
Payments to existing pensioners will be made from cash transferred to the Prudential by the fund.
l Are you affected by the pension fund shortfall? If you are then e-mail bryan.carter@lancasterguardian.co.uk