PIERCE

MANUFACTURING

I N C.

BULLETIN
TO:

TAK-4® Suspension Customers
Pierce Dealers

FROM:

Pierce Customer Service

DATE:

February 25, 2015

RE:

TAK-4® Ball Joint Inspection Reminder
Service Bulletin # 355.1

This bulletin is a reminder for Pierce customers to periodically inspect their TAK-4® suspension like any other system on
their truck. The TAK-4® suspension has components such as ball joint assemblies that can wear or become damaged
during normal use. Failure to periodically inspect these ball joint assemblies can produce an unusual noise in the front
end of the vehicle and could eventually lead to separation of the ball joint assembly. There are two ball joint assemblies
on each side of the suspension that connect the wheel spindle to the A-arm assemblies.

Ball Joint
Assemblies
Ball Joint
Assemblies

Your Custom Chassis Operators Manual will refer you to the service manuals when inspecting the TAK-4® suspension.
The people doing your regular maintenance should refer to the Pierce TAK-4® Independent Suspension Service Manual
for all the details, but the following highlights those specific to the ball joint assemblies.
There are two different ball joint assemblies and they are not interchangeable.

Page 1 of 3

Ball Joint “A”

Ball Joint “B”

Boots: In either case it is important that the boots be inspected for tears, splits every 6 months. You may also see signs
of the grease leaking out of the boots if they are damaged. In the case of ball joint “A”, you need to feel between the
folds of the boot for any damage. With ball joint B look for any separation from the retaining ring and or damage to the
boot itself. The two photos below are examples of failed boots.

Ball Joint “A”

Ball Joint “B”

Vertical Movement: In addition to a damaged boots, the vertical free play or movement of the ball joint needs to be
monitored over time. If the movement of the ball joint is allowed to go over the design limits, you could start hearing
unusual noises in the front of the vehicle, especially when going over bumps. Again, if you let it get worn many times
over the limit, the ball joint could separate. Out of limit ball joint assemblies need to be replaced by trained technicians.
Note that a damaged boot accelerates the wear of the ball joint assembly.
The TAK-4® Service Manual now recommends that the first inspection be done at 36 months. This is measured by a
trained technician using a dial indicator. The amount of wear allowed for the ball joint assemblies are the following:
Ball Joint “A” – Upper ball joint – Maximum of 0.015 inches

Lower ball joint – Maximum of 0.025 inches

Ball Joint “B”– Upper and lower ball joints – Maximum of 0.080 inches

Page 2 of 3

Long Term Inspection:
Pierce recommends that once you get past the 36 month point, inspect the boots and ball joint vertical movement every
12 months. Contact your dealer for questions and or maintenance support.
TAK-4® Training:
In the event that you (Pierce dealer representative or Pierce customer) would like to attend one of our in depth
maintenance training seminars on the TAK-4® system, you can sign up for one of the following classes at our regional
training sessions as noted below. For more information and to register please use the following link;
http://www.piercemfg.com/en/service/maintenance-and-training.aspx

2015 Regional Training Schedule - Las Vegas, Nevada
• May 11-15, 2015
Click on the red text above to open an Adobe PDF document containing details on the classes being offered and the class schedule.
Added 10/10/14
File Type: PDF, File Size: 3,429k

2015 Regional Training Schedule - Appleton, Wisconsin
• February 24-27, 2015
• March 23-27, 2015
• April 28-May 1, 2015
• June 8-12, 2015
• August 3-7, 2015
• October 5-9, 2015
• November 2-6, 2015

Page 3 of 3