that can be unbolted from the rear axle housing. The integral
carrier type is a one-piece unit. It is serviced by removing a
sheet metal inspection cover, located at the rear of the housing.
A modified rear axle housing is used on vehicles
having independent rear suspension. The internal construc-
tion of the housing is identical to those used on live axles.
(A version of this housing is used on some front-wheel drive
vehicles that have the engine mounted longitudinally.)
The rear drive axles transfer power from the side gears
to the rear wheels. Drive axles can be solid or independ-
ently suspended. Solid axles are splined with, and supported
by, the side gears at the inboard end. The outboard end is
supported by axle bearings. The axle bearing can be
installed on the shaft or in the housing. Bearings that are
installed on the shaft are usually packed with grease.
Bearings that are installed in the housing are lubricated by
rear end lubricant. Seals are used to keep lubricant from
leaking out of the rear axle housing.
Solid axles can be semi-floating or full-floating. In the
semi-floating axle, the weight of the vehicle goes through
the axle bearing to the shaft and out to the wheel. In the
full-floating axle, the axle drives the wheel but does not
carry any of the vehicle weight. Most passenger cars have
semi-floating axles.
Independently suspended drive axles resemble drive
shaft assemblies. They consist of a central shaft with flexi-
ble joints and stub axles on each end. The flexible joints
can be conventional U-joints or CV joints. They allow
each wheel to move independently of the vehicle body
and of each other.
Review Questions—Chapter 16
Please do not write in this text. Place your answers on
a separate sheet of paper.
1. Which of the following items does not belong with
the others?
(A) Rear axle assembly.
(B) Final drive.
(C) Differential.
(D) Rear end.
2. What is independent rear suspension?
3. Which rear end components change the direction of
power flow by 90°?
4. How can rear axle ratio be determined?
5. If the drive pinion gear has 10 teeth and the ring gear
has 35 teeth, what is the rear axle ratio?
6. Describe the construction of a drive pinion gear.
7. Which of the following parts is used to set pinion
bearing preload?
(A) Jam nut.
(B) Crush washer.
(C) Lock washer.
(D) Castle nut.
8. The convex side of ring gear teeth is the _____ side, and
the concave side of ring gear teeth is the _____ side.
9. The standard differential is composed of meshing
_____ and _____ gears enclosed in a differential case.
10. In terms of their construction, what is the major
difference between a standard differential and a limited-
slip differential?
11. The Torsen differential is a locking differential that
uses a _____.
(A) multiple-disc clutch
(B) cone clutch
(C) dog clutch
(D) worm gearset
12. Explain the function of the rear axle housing.
13. Describe the two major kinds of carriers.
14. In the _____-floating axle, the weight of the vehicle
passes through the axle bearing to the drive axle and
on to the wheel and tire.
15. In a(n) _____-floating axle, the wheel does not carry
any of the vehicle weight.
ASE-Type Questions—Chapter 16
1. Technician A says that every rear axle assembly has a
housing, a differential assembly, and rear drive axles.
Technician B says that every rear axle housing has
axle tubes. Who is right?
(A) A only.
(B) B only.
(C) Both A and B.
(D) Neither A nor B.
2. The most common rear axle assembly failures are
_____.
(A) axle bearing failures
(B) pinion yokes failures
(C) cracked spider gears
(D) stripped ring and pinion gears
3. Each of the following is a primary function of the
differential assembly except:
(A) multiplying engine power.
(B) allowing the vehicle to make turns.
(C) supporting and aligning the drive axles.
(D) redirecting power flow to the rear wheels.
4. Rear axle ratio can be found by dividing the number
of teeth on the ring gear by the number of teeth on
the _____.
(A) side gear
(B) spider gear
(C) drive pinion gear
(D) axle end gear
332 Manual Drive Trains and Axles