cotta-logoMill Log Group of Companies is your Cotta Authorized Distributor

Cotta Transmission and Gearboxes….A Driving Force for More Than A Century.

1906 — While Henry Ford’s innovative, moving automobile assembly line was revolutionizing manufacturing methods, engineer Charles Cotta established the Cotta Transmission Company. He introduced his own breakthrough: the constant-mesh shifting transmission; soon Cotta supplied the emerging automobile and truck industries with main transmissions.

1940s — Cotta began a shift to industrial products and the off-highway and construction specialty vehicle markets.

Mid 1960s — Cotta added a line of high-speed transmissions (the now well-known “SN” line).

Over the years, Cotta diversified into various products including hydraulic pumps and coal augers.

Today – Cotta (with production facilities in Beloit, Wisconsin) is a trusted, leading manufacturer of top-quality, precision-engineered transmissions for a wide range of specialized mobile and stationary applications: vocational trucks, defense, off-highway, aerospace, heavy industry, well-drilling, mining, marine and more.

Manufacturing Geared for Quality.

At our 70,000-square-foot Beloit facility, capability, efficiency and process flow come together to ensure the delivery of our most important product: quality. Cotta designs in accordance with American Gear Manufacturers Association standards. Lean Manufacturing is the rule; 5S techniques employed in all departments improve standardization in the production process. Adherence to a rigid Supplier Certification and Selection program ensures constant control of material quality.

Quality is monitored systematically and comprehensively. First-piece inspection is conducted on every machining sequence, focusing on quality at the source to support our “zero-defect” policy.

We assemble and test every transmission we ship — 100%. All products are backed by an excellent standard warranty. Extended Warranty packages are available.

Product Overview

Powered by Custom-Engineering Expertise.

Cotta’s has 5,000+ existing product designs available, plus our experienced engineers and craftsmen can take virtually any new transmission application from concept to delivery at our Beloit, Wisconsin production facility. Our engineers and designers work with customers to develop solutions and then deliver drawings in virtually any CAD format to drop into the customer’s own design.







  • Single- or dual-speed
  • Capacity up to 1,000 horsepower
  • Front- and rear-mounted disconnects
  • Multiple shifting options
  • Extensive PTO and accessory drive options
  • Multiple shifting options
  • Extensive PTO and accessory drive options
  • Ground helical gears for higher load capacity and quiet operation
  • Multitude of gear ratios
  • Available with or without lube pumps
  • Direct engine or independent mount
  • Ground helical gears
  • Class 30 gray or ductile-iron cast housings
  • Torsional couplings
  • Over-center or hydraulic clutch
  • Rubber block drives
  • Capacities to 2,500 horsepower
  • Multiple ratios to as high as 7:1
  • Standard SAE flywheel housings
  • Planetary drives
  • Right-angle drives
  • Top-head or top mast drives
  • Multiple-speed transmissions
  • Turbine reduction drives
  • Heavy-duty pump drives
  • Compound gearboxes
  • Standard and custom designs
  • Capacities in excess of 3,500 horsepower
  • SAE, DIN or customer-specified output
  • Up to 12 outputs per drive unit
  • Up to 5,000 horsepower
  • Output capacity of up to 80,000 RPM
  • Various aerospace, automotive or industrial testing applications
  • Available as a speed reducer or increaser
  • Designed with single or multiple outputs
  • Hybrid coaxial outputs

Repair and Rebuild

Achieve optimum performance once again from your reliable Cotta transmission…

Mill Log Group of Companies offers complete expert remanufacturing or repair of your Cotta products backed by our standard warranty. We’ll provide a thorough, 100% disassembly inspection, install genuine new or reconditioned Cotta OEM parts, and clean, reassemble, and test your transmission to the same standards as new. .

Call today to schedule the service you need …from complete rebuilds to minor repairs.