P purchased a motorhome manufactured by General Motors Corporation (GM-D) from Bluff (D). P sued Ds alleging breach of express warranty. The New Vehicle Warranty for the motor home was for a period of 12 months or 12,000 miles, whichever first occurs, D warranted to repair any defective or malfunctioning part of the Motor Home -- except tires and tubes which are warranted separately by the tire manufacturer. The warranty covered only repairs made necessary due to defects in material or workmanship. The trial court disposed of the case on statute of limitations grounds. The trial court found that the four-year statute of limitations began to run on June 25, 1973, when tender of delivery was made and that the instant action was not filed within the original limitations period, nor was it filed within the one-year period allowed. P appealed contending that the warranty explicitly extends to future performance of the goods and discovery of the breach is when the statute begins to run.