Multilink Rear Suspensions Of The Toyota Avensis '03

[Alberto Michelatti]

Hi!

Since the presentation of the Avensis '03 it has been written that "the rear double wishbone suspension module is derived from the Toyota Celica sports coupé, widely recognised as one of the best handling cars in its class". On the Avensis '03 "an additional link has been added to give optimised toe alignment control, which improves rear stability under hard cornering giving better response".

After some researches, and checking directly, I discovered that the rear suspensions of the Avensis '03 and of the Celica '99 are not truly "double wishbone" type (1 upper triangular A-arm, 1 lower triangular A-arm, 1 horizontal toe control arm) but, rather, are trapezoidal type (1 trapezoidal-linked lower L-arm + 1 single upper arm) in the case of the Celica '99 and multilink type (1 trapezoidal-linked lower L-arm + 1 single upper arm + 1 rear horizontal toe control arm), with the light ability of steering, in the case of the Avensis '03. However the effects of these suspension schemes are quite similar to a conventional "double wishbone" type.

On the Celica '99 and on the Avensis '03 the lower L-arm comprises a longitudinal tubular arm welded to a pressed-steel transversal arm. The lower L-arm is linked to the body frame with a longitudinal vertical rubber bushing in the front of the rear wheel and with a transversal vertical rubber bushing linked to the body frame near the middle of the rear axle. Coil springs and shock absorbers are mounted concentrically on the tubular lower arms at their mid-length. The stabilizer bar is linked directly to the hubs on the Celica '99 and linked directly to the longitudinal tubular arms of the lower L-arms on the Avensis '03.

On the Celica '99 the hub is linked to the longitudinal tubular arm of the lower L-arm with 2 vertical rubber bushings and is linked to the single upper arm with 1 vertical rubber bushing.

On the Avensis '03 the hub is linked to the longitudinal tubular arm of lower L-arm with 1 horizontal front rubber bushing and with 1 vertical rear rubber bushing, and is linked to the single upper arm with 1 vertical rubber bushing. On the Avensis '03, moreover, there is an additional rear horizontal toe control arm that, due to the vertical rear rubber bushing play, is able to thinly steer the wheel under hard cornering.

Toyota Celica '99 rear suspension

Toyota Avensis '03 rear suspension

Toyota Avensis '03 rear suspension and horizontal toe control arm

Alberto.