The carrier we use for GAP insurance has these restrictions on their policy:

• Maximum Limit of Loss: $50,000
• The claim settlement may not cover the entire Gap due, when your loan's Original Amount Financed exceeds 120% of MSRP (new vehicle) or NADA Retail Value (used vehicles), plus 30% of Value allowable for Additional Financed Items like Credit Life or Service Contracts. The claim settlement does not cover late charges or other penalties due to your lender.
• Your loan amount financed must be less than or equal to $100,000.
• Your loan term must not be greater than 84 months.
• The loan must not have a balloon payment due at the end of the term.
• The maximum APR is 12.5%

These are specific to the carrier we use. Some policies may or may not have these restrictions.

The reason for this restriction are purely mathematical. GAP insurance, just like all other types of insurance are based upon actuarial study of the factors that affect a contract.