Stock Rubber Differential Bushings
Problem:
The stock rubber differential lower bushings compress and deteriorate over
time. This causes increased pinion angle under load which leads to slower
acceleration. All cars have rubber bushings that are responsible for maintaining
correct pinion angle. 2 degrees negative pinion angle is what the Ford
shop manual calls for. Problem is the rubber compresses over time and causes
increased positive pinion angle. Most people don't realize how bad the
differential bushings are until they replace them. Below are a few pictures
of what will happen to the stock rubber differential bushings over time.
Some of the symptoms of compressed rubber bushings are: slight acceleration
delay; driveline vibration; Soft transmission shifts up or down; clunk
when shifting into reverse.
The OEM rubber differential bushing can look fine but upon closer
inspection.
Passengers side upper bushing completely crushed.
Rubber begins to separate over a few years this bushings was 8 years
old.
As you can see this differential bushing has compressed and allowed
dirt and small rocks
to become imbedded into it. When you remove the bushings be sure
to check the metal surface for any
rough and or sharp surfaces that could cut the bushings.
Dryrot has caused the bushing to crack. Time and normal wear has
caused the bushing to fail.
Cure:Replace
the OE rubber bushings with NEW Polyurethane bushings
available from MN12 Performance Inc.
To see installation instructions for the IRS100 click HERE.
To purchase IRS100 click HERE.