Here's the part #s and prices on the rear axles. Because the price jumps up quite a bit for '03/04 Sport, they would seem to be a heavier part. From the sketch, the axles have a swing arm that mounts at 90* from the beam so it appears they work on a torque/twist principal. So heavier/thicker should control sway better.
AXLE ASSEMBLY
2001.............................5272550AC........ ....$163.00
2002.............................5272550AE........ ....$163.00
2003(std susp, firm feel)...03 4656440AG.......$174.00 (Base?)
2004(std susp, firm feel)...04 4656440AH.......$174.00
2003(sport susp).............03 5272914AA.......$329.00 (Turbo?)
2004(sport susp).............04 5272914AB.......$329.00
EXTERNAL ANTI-SWAY BAR
2001-2002...................01-02 5272309AA......$54.95
2003-2004...................03-04 5272923AA....$106.00
A few other parts on the '03 were common with '01-02 but changed on the '04. I have no part #s for 2005.
By what the prices indicate, there doesn't seem to be a big difference at the '03 change over unless it was the "Sport".
The "name" on the '03-04 std susp does say "Firm Feel" for the base PT, so that may confirm Chrysler's explanation somewhat about the lack of an external bar.
I guess we need a volunteer with an'01-02 and one with an '03-04. Have them drive faster and faster in a circle 'till one falls over. [
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