QA1 5255 Installation Instructions Manual

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Figure 1

READ ALL INSTRUCTIONS CAREFULLY AND THOROUGHLY PRIOR TO STARTING INSTALLATION. PRODUCTS THAT HAVE BEEN INSTALLED ARE NOT ELIGIBLE FOR
RETURN. USE THE PROPER JACKING LOCATIONS. DEATH OR SERIOUS INJURY CAN RESULT IF INSTRUCTIONS ARE NOT CORRECTLY FOLLOWED. A GOOD CHASSIS
MANUAL, AVAILABLE AT YOUR LOCAL PARTS STORE, MAY ALSO AID IN YOUR INSTALLATION.

QA1 WARRANTS THAT THE PRODUCTS WILL BE FREE FROM DEFECTS IN MATERIAL AND WORKMANSHIP FOR ONE YEAR FROM DATE OF SALE TO THE ORIGINAL
PURCHASER. QA1 MAKES NO OTHER WARRANTY OF ANY KIND, EXPRESS OR IMPLIED. QA1 SHALL HAVE NO OBLIGATION UNDER THE FOREGOING WARRANTY
WHERE THE DEFECT IS THE RESULT OF IMPROPER OR ABNORMAL USE, YOUR NEGLIGENCE, VEHICLE ACCIDENT, IMPROPER OR INCORRECT INSTALLATION OR
MAINTENANCE, NOR WHEN THE PRODUCT HAS BEEN REPAIRED OR ALTERED IN ANY WAY. QA1’S LIABILITY IN THE CASE OF DEFECTIVE PRODUCTS SUBJECT TO
THE FOREGOING WARRANTY SHALL BE LIMITED TO THE REPAIR OR REPLACEMENT, AT QA1’S OPTION, OF THE DEFECTIVE PRODUCTS.

THE USER UNDERSTANDS AND RECOGNIZES THAT RACING PARTS, SPECIALIZED STREET ROD EQUIPMENT, AND ALL PARTS AND SERVICES SOLD BY QA1 ARE
EXPOSED TO MANY AND VARIED CONDITIONS DUE TO THE MANNER IN WHICH THEY ARE INSTALLED AND USED. QA1 SHALL BEAR NO LIABILITY FOR ANY LOSS,
DAMAGE OR INJURY, EITHER TO A PERSON OR TO PROPERTY, RESULTING FROM THE INSTALLATION, DIRECT OR INDIRECT USE OF ANY QA1 PRODUCTS OR
INABILITY BY THE BUYER TO DETERMINE PROPER USE OR APPLICATION OF QA1 PRODUCTS. WITH THE EXCEPTION OF THE LIMITED LIABILITY WA RRANTY SET
FORTH ABOVE, QA1 SHALL NOT BE LIABLE FOR ANY CLAIMS, DEMANDS, INJURIES, DAMAGES, ACTIONS, OR CAUSES OF ACTION WHATSOEVER TO BUYER
ARISING OUT OF OR CONNECTED WITH THE USE OF ANY QA1 PRODUCTS. MOTORSPORTS ARE DANGEROUS; AS SUCH, NO WARRANTY OR REPRESENTATION IS
MADE AS TO THE PRODUCT’S ABILITY TO PROTECT THE USER FROM INJURY OR DEATH. THE USER ASSUMES THAT RISK!

• Floor Jack • Jack Stands • Tire Chocks • 18mm socket and wrench

• Torque Wrench • Blue Loctite™ • Grease Gun • Lug Wrench

Removal of Stock Trailing Arms

1. Place the car on level surface and place tire chocks in front of and behind the front tires.

2. Support the rear of the car on jack stands and remove the rear wheels.

3. Place a floor jack under the differential and lift up slightly to remove tension from the trailing arm bolts - make sure not

to lift the car off the jack stands. See Figure 1.

Note: Keep the jack under car during the complete removal and

installation procedure. Do not remove both trailing arms at the same
time or the axle will rotate and the trailing arm installation will be
much more difficult.

4. Start with either trailing arm and remove the rear bolt. Note: Re-

Install the bolts in the same direction as originally installed.

5. Remove the front trailing arm bolt and remove the trailing arm from

the car.

6. Clean the frame at trailing arm pivot area with a wire brush.

21730 Hanover Ave.
Lakeville, MN 55044

www.QA1.net

INSTALLATION INSTRUCTIONS

QA1 P/N 5255 Adjustable Trailing Arms

1979-2004 Mustang

• DISCLAIMER / WARRANTY •

TOOLS AND SUPPLIES REQUIRED

1

REV 02052016

Differential Bushing Installation

Note: Bushings supplied with these arms are designed to be used with the original differential bushing shells. Do not press

out bushing shells.

1. Remove the rubber and the inner sleeve from the outer bushing shells and clean the original shells thoroughly.

2. Using the supplied grease, lube the inside and flange of the O.E. bushing shell.

3. Lightly grease the inside and outside of the polyurethane bushing and install bushing into shell.

4. Grease the outside of the steel sleeve and insert it into the polyurethane bushing.

5. Install the thrust bushing.

Installation of QA1 Adjustable Trailing Arms

Note: QA1 Adjustable trailing arms are fully assembled, greased and

ready to install.

1. Install the new trailing arms with the grease fittings facing down,

locating the front bolt first.

2. Place one drop of blue Loctite™ on clean threads and torque the

nut to 70 lb.ft. The trailing arm should pivot smoothly.

3. Pivot the trailing arm into position over the polyurethane bushing

and thrust washer. Install the rear trailing arm bolt in same
direction as the original.

4. Place one drop of blue Loctite™ on clean threads and torque the nut to 70 lb.ft.

5. Although QA1 Trailing Arms are pre-lubed, you may want to finish your installation by lubing the front bushings with a

grease gun. Be sure to replace the dust caps on the zerk fittings to prevent dirt and corrosion from damaging the fitting.

Notes:

1. QA1 Adjustable Trailing arms come pre-adjusted to stock length. Pinion angle can be adjusted by loosening the jam nuts

on the arms and turning the aluminum adjuster sleeve in the center of the arm. Both arms should be adjusted evenly. A
properly installed and adjusted trailing arm will have the spherical ball straight and parallel with the ball housing. If the
ball is twisted in its housing when installed, the arm could fail during suspension articulation. After adjustment has been
made, use a drop of Loctite™ on threads at jam nuts.

2. Re-torque all bolts after the first 10 miles and jam nuts should be checked periodically for tightness.

2

REV 02052016