Shipping customers of 14 trucking companies charged with double billing are scheduled to receive up to $2 million in refunds from those truckers in the aftermath of successful federal court action brought by the Interstate Commerce Commission.

Last November, the ICC began to bring court action against 23 Midwest truckers for withholding more than $4.5 million in duplicate payments from shippers who had contracted the truckers.

At the time, of the first civil suits the action was called "only the tip of the iceberg" by an ICC official, who said that 20 percent of all firms investigated were guilty of the practice.

The ICC complaints charged that the truckers would collect twice for the same shipment - either through double billing or collecting through prepayments and bank payments and not informing the shipper that the bill was paid twice.

Unless the shipper noticed the error and informed the truck, the double billing would be ignored by the trucker, and refunds would not be sent.

Of the 23 truckers named in the actions, 14 have now been ordered by four different federal district courts to identify and refund duplicate payments and to implement plans to identify and refund such payments in the future.

Similar court orders are being sought against the remaining nine firms, with an additional $2.5 million in alleged duplicate payments involved.

Among the companies victimized by the practice wereWestinghouse Electric Co., International Harvestser, American Motors Corp., Bendix Corp., Firestone Tire & Rubber Co. and United Air Lines.

The ultimate loser in the duplicate billing scheme was the public, according to ICC official Ivan Schaeffer, "because the shippers are just passing the added costs on to the consumer."

The court ordered refunds from the following trucking concerns: Gateway Transportation Co., La Crosse, Wisc.; Badger Freightways Inc., Sheboygan, Wisc.; Brada-Miller Freight System Inc., Kokomo, Ind.; Turner Trucking Inc., Lebanon, Ind.; United Trucking Service Inc., Detroit, Michigan Transportation Co., Dearborn; R-W Service System Inc., Taylor Mich.; Sturm Freightways Inc., Peoria, Ill.; Sims Motor Transport Lines Inc., Chicago; O.K. Motor Service Inc., Summit. Ill.; Liberty Trucking Co., Chicago; Freeport Fast Freight Inc., Chicago; Artim Transportation System Inc., Gary, Ind.; and Transport Motor Express Inc., Ft. Wayne, Ind.