The Fuel Mileage Dr. Inc. Shop Our Performance Tuners Our “Secret Sauce” and Best Selling Product! Bully Dog Heavy Duty GT Diesel Fuel Mileage Tuner $1,899.00 Add to cart Bully Dog Heavy Duty WD Fuel Mileage Tuner $599.00 Add to cart Bully Dog Heavy Duty ECM Tuner $999.99 Select options Big Boss Performance Tuner by PDI $2,350.00 Select options Your Official Dealer of: Turbo Chargers: Cummins N14 and ISX Big Boss Stage 1 Turbo $1,500.00 Add to cart Big Boss Caterpillar C12 Stage 1 Turbo $1,500.00 Add to cart Big Boss Caterpillar 3126 | C7 Stage 1 Turbo $2,150.00 Add to cart Caterpillar 3406, C15, & C16 Series 700HP Stage 2 Turbo $2,000.00 Add to cart Exhaust Manifolds: CAT 3406E/C15/C16 Low Mount Exhaust Manifold $1,450.00 Add to cart Detroit Series 60 12.7L & 14.0L Freight Liner/Western Star Exhaust Manifold $1,600.00 Add to cart CAT C13 Exhaust Manifold $1,450.00 Add to cart Cummins N-14 Celect Plus Exhaust Manifold $1,600.00 Add to cart