10411 Airport Rd Everett, WA 98204

Mon-Fri: 8:00am-5:30pm

For Service - 425-249-0296

For Parts - 866-631-0196


The Service Center at Randy’s Ring & Pinion has been in business for over 30 years. Randy’s is dedicated to driveline repair and replacement. Our mechanics are the best in the industry and have immediate access to over 6,000 parts to get the job done quick.

Find the rating for your street tires (example: 225/70R15 or 225/70/15). The first number will be the Width (in millimeters), the second will be the Aspect, while the third is the size of the wheel (in inches).
Place your corresponding numbers into the fields below to calculate your tire height.
Width Aspect Wheel
To find your vehicle's RPM enter your Ring and Pinion Gear Ratio, Tire Height, and Speed then click "Solve".
Ratio Tire Height Speed
Auto* AOD* Manual* 5 Speed*
* Auto = D in an AOD
* AOD is calculated at .70 transmission ratio
* Manual = 4th in a 5 speed
* 5 speed is calculated at .80 transmission ratio
Enter Ring & Pinion Ratio, Tire Height, Speed (mph), and Transmission Ratio then click "Solve" to calculate Transmission RPM
R&P Ratio Tire Height Speed Trans Ratio
Enter the number of teeth on your Ring Gear and your Pinion Gear then click "Solve".
Ring Gear Pinion Gear Gear Ratio
Enter your Bore Size, Stroke Length, and number of Cylinders; select either inches or millimeters then press "Solve" to find your exact engine displacement.
Bore Size Stroke Length Cylinders
Measurement Type

Engine Displacement Cubic Inches
Cubic Centimeters
Convert liters to cubic inches and vice versa. Useful for determining your engine size for each metric
Cubic Inches to Liters
Cubic Inches Liters

Liters to Cubic Inches
Liters Cubic Inches
Enter the length of your piston rod under Rod Length and the stroke length of your engine crankshaft under Stroke then press "Solve" to find the rod ratio for your vehicle.
Rod Length Stroke Rod Ratio
Enter your vehicle's torque in ft. lbs for any given RPM then click the "Solve" button.
Torque RPM Horsepower

Schedule an Appointment Today! 425-249-0296

Most jobs can be completed in just one day!

Service Center Info

About Us


Stay Connected!

Receive E-Mail Updates

Email: service@ringpinionservice.com

Call: 1-425-249-0296

The Service Center at Randy's Ring & Pinion: 10411 Airport Road Everett, WA 98204

Copyright © 2016 Ring Pinion Service, Inc®

Schedule an Appointment Today!