Understanding Differences in Automotive Differentials

See 11 different types of automotive differentials and learn how they work. This video is intended for students in the AUSV 1220 Manual Drivetrain class at Weber State University with Professor John D. Kelly.

CORRECTIONS:
1. The differential I called a "Detroit Locker" is not a Detroit Locker. It is just an Eaton Posi Limited Slip differential. A Detroit Locker uses dog teeth and is a truly locking differential. Thank you goes out to Keith MacDonald for catching my error.
2. I did not adequately explain how the clutch packs of a limited-slip differential are applied. The simple rotation of the side gears versus the differential pinion gears does not cause clutch packs to apply; otherwise, the clutches would apply when turning corners at low load (low torque). Torque from the engine (or another propulsion source) is necessary. The more torque you supply to the differential side gears, the higher the force on the angled (ramped) teeth, the higher the force on the clutch packs. Thank you to several viewers for pointing out my omission.
3. There is more than one style of Torsen differential. See the JTEKT Corporation's website for more information https://www.jtekt.co.jp/e/products/automotive/driveline/differential02.html
4. I incorrectly described the operation of the original 1956 Dana limited-slip differential. The pinion pins on the original Dana differential have tapered ends. The pins sit in four V-shaped ramps in the differential case. Under a load, the differential case applies rotational torque to the pinion pins, causing them to slide up the V-shaped ramps. This action applies an outward force to the side gears and the clutch packs. Thank you to several viewers for pointing out my error.

TIMELINE
0:00 Start
0:08 Introduction
0:32 Open Differential
3:55 Power flow through a differential
6:51 Side gear backlash control
9:09 Differential Demonstration
10:21 MUST SEE Differential Equations
13:12 Automotive differential history
14:44 Dana Corporation's 1955 invention of the automatic locking differential
15:33 Various names for Dana's locking differential
17:23 See a 1963 Chevrolet positraction differential with clutch packs
24:00 How rotating gears apply a clutch pack
26:35 Why limited-slip additive may be required for a clutch-type differential
28:46 See a 1970s era GM positraction differential with clutch packs
29:40 See a 1984 Chevrolet Corvette Limited-Slip differential with clutch packs
30:02 See a 2012 Eaton Posi Limited-Slip differential with clutch packs
34:00 MUST SEE See a worn out 2010 Chevrolet Camaro SS Limited-Slip differential with clutch packs
38:00 See a broken 2005 Jeep Wrangler Rubicon Torsen Type B style limited-slip differential with an air locker
43:51 MUST SEE See the pieces of a Torsen Type B style differential and see how it works
48:03 See a 2002 Toyota Tacoma Electric Locking Differential
51:00 See the Eaton Detroit Trutrac (Similar to the Torsen Type B differential design)
49:55 See a spool with no differential action
53:40 See a Mini-Spool and how to install it
56:35 See the Eaton Locker and learn how it works
1:00:45 Final wrapup

ABOUT US:
Weber State University (WSU) Davis Campus - Automotive Technology Department - Transmission Lab. A technical description and demonstration of 11 different types of differentials. We teach current vehicle technologies to our automotive students at Weber State University and online. For more information visit: http://www.weber.edu/automotive

This video was created and edited by Professor John D. Kelly at WSU. For a full biography, see http://www.weber.edu/automotive/J_Kelly.html

Visit my other youtube channel https://www.youtube.com/user/vibratesoftware to see the amazing NVH app for vibration diagnosis!

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