Weber State University (WSU) - Automotive Technology Department - Transmission Lab. This episode covers the difference between a part-time Four Wheel Drive (4WD) transfer case and a Full-time All Wheel Drive (AWD) transfer case on a pickup truck or Sport Utility Vehicle SUV.
Timeline:
0:00 Start
0:09 Introduction
0:20 Standard transfer case operation piece by piece
8:20 The three positions of the Range sleeve. (High, Neutral, and Low)
13:00 Triple Cone Synchronizer for the 4WD mode shift
14:00 Conditions required to shift into or out of 4WD Low
14:38 Conditions required to shift into 4WD while driving at highway speeds
18:15 Why you should not drive on dry pavement in 4WD
20:14 Center differential transfer case operation piece by piece
21:56 Center differential transfer case compared to an open differential rear axle
23:05 What makes a center differential transfer case different from a 4WD transfer case?
23:50 The pieces of the Torsen Type C center differential
25:09 The operation of the Torsen Type C center differential
28:40 The operation of a center differential on vehicles with stability control and AWD
30:33 Assembly of the components of a center differential transfer case
37:07 See the open differential action of the center differential
38:20 Why you can drive on dry pavement in AWD
38:57 See the 4WD high mode bypass the center differential
39:55 See the second planetary gear set that allows 4WD Low range
40:53 Summary
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/lsd.html
This video helps satisfy the requirements of the following NATEF Tasks:
3.F.5 – 4WD/AWD - Diagnose noise, vibration, and unusual steering
concerns; determine necessary action - Priority Level 3
Questions for teachers:
1. What are the three modes of operation of a typical 4WD transfer case?
2. Why is a triple cone synchronizer needed to shift into 4WD while driving at highway speeds?
3. When shifting the transfer case into 4WD while driving, what parts must start rotating that was previously stopped?
4. Why you should not drive on dry pavement in 4WD?
5. What additional part does a center differential transfer case have that a traditional 4WD transfer case does not have?
6. Visit the JTEKT Corporation's website for more information https://www.jtekt.co.jp/e/products/lsd.html What is a Torsen Type-C differential?
7. How do vehicles with stability control and AWD control front to rear driveshaft speed differences and left to right wheel slip?
8. Why is it okay to drive on dry pavement in AWD with a center differential transfer case?
9. Tell me one thing you learned from this video
http://www.weber.edu/automotive
This video was created and edited by John D. Kelly at WSU. For a full biography, see http://www.weber.edu/automotive/J_Kelly.html
Donate to the Department of Automotive Technology at Weber State University here: http://advancement.weber.edu/Automotive