Rear /Air Suspensions

Question 1

what are some key functions the rear suspension must perform

Answer 1

• Support the payload of the vehicle.
• Transmit acceleration and braking forces to the frame.
• Articulate tandem axles for all road conditions.
• Provide an acceptable ride both loaded and unloaded.
• Track properly to provide safe steering.
• Be easily serviced and maintained.

Question 2

Main types of rear suspensions

Answer 2

• spring
• walking-beam
• air

Question 3

what do suspension springs refer to

Answer 3

multileaf or taper leaf

Question 4

What type of rear spring suspensions does PB use?

Answer 4

Slipper type ends

-forces spring contact to move to middle when loaded

Question 5

what ratings does PB offer in walking-beam suspensions

Answer 5

35k to >65k pounds

Question 6

how are walking beam suspensions connected

Answer 6

2 beams - 1 on each side of vehicle are connected to forward and rear drive axles

Question 7

how many points of contact do walking beam suspensions use

Answer 7

They use 4-point frame mounting

Question 8

Where are walking beam suspensions used?

Answer 8

reliable and perform well in heavy-duty on/off hwy vocational applications, but do not ride as well as air suspension

Question 9

on which applications is PB low air leaf available?

Answer 9

as a tandem suspension application on Class 8 and single or tandem Class 7 vehicle

Question 10

Capacity of PB low air leaf

Answer 10

tandem capacity of 40k lbs, Max GCW of 143k pounds

Question 11

What carries most load on low air leaf

Answer 11

Air bags mounted to the leaf springs on each side of each axle carry most of the load

Question 12

What is low air leaf designed for

Answer 12

for use with “high cube” general freight trailers or for auto carriers or flat beds, which require a low frame or fifth wheel height

Question 13

What is low air leaf ride height

Answer 13

ride height of 19.5-inches, which is approximately 2.5-inches lower than standard

Question 14

How much lower is low-low air leaf compared to low air leaf?

Answer 14

low-low is 2 inches shorter

Question 15

Capacity of flex air system and air leaf with tracking rods

Answer 15

Rated capacity of 38k lbs, max GCW of 143k pounds

Question 16

which suspension is PB lightest

Answer 16

Flex Air

Question 17

Who is flex-air perfect for

Answer 17

Flex-Air is perfect for on-highway customers who need
the stability of lower ride height for high cube van
trailers

Question 18

What is air leaf with tracking rods ideal for

Answer 18

very effective for all on-highway freight services. The overall durability of its design also allows it to be used in some on/off-highway applications, such as semi end-dump tractors

Question 19

Which air suspension is designed for heavy duty on or off highway applications?

Answer 19

Air Trac

Question 20

What is difference in Air Trac vs. Air Leaf w/tracking rods?

Answer 20

Air trac adds longitudinal tracking rods to transmit acceleration and braking to the frame

Question 21

What are air trac suspensions best designed for?

Answer 21

Severe off-highway applications such as logging, refuse, dump, and low bed

Question 22

What capacities are available with Air Trac?

Answer 22

The Air Trac is available in both single and tandem drive axle configurations.

Single drive application is available in 20,000- and 23,000-pound capacities

tandem drive applications in 40,000-, 44,000-, and 46,000-pound capacities.

Standard axle spacing for the dual drive Air Trac is
52-inches. Optional axle spacings of 54, 60, 65, and 72-inches are also available.

The Air Trac has a maximum GCW rating of 125,000 pounds for single axles

180,000 pounds for tandems

Question 23

what does height control valve do

Answer 23

lets air in or out of suspension based on varying loads