May I take issue with your correspondents “M. L. T.” and Mr. Hutchinson, over the inherent unsafety of independent rear suspension by swing axles. It is perhaps significant that although the Mercedes-Benz racing cars of 1938/9 followed Dr. Porsche’s earlier Auto-Unions in having de Dion rear suspension, the W196 Mercedes with which Fangio won the World Championships of 1954 and 1955, had swing axles. So far as I can discover, no modern racing car employs the de Dion layout.
The criticism most frequently levelled at i.r.s. by swing axles is that wheel camber changes under cornering stress and in some circumstances this can lead to skidding when a rear wheel “tucks in” under the sideways thrust on the car. The system developed by Daimler-Benz uses a horizontal compensating spring mounted above the axle. This limits the degree of deflection possible and helps to give Mercedes-Benz cars their entirely “neutral” steering characteristics.
Mercedes-Benz are probably more experienced in independent rear suspension than any other manufacturer since all cars – not just the sports models – have been fitted with i.r.s. since 1931. With men like Prof. Dr. Nallinger and Rudi Uhlenhaut in charge of research and development, is it likely that Mercedes-Benz would offer to the public a suspension system which was “inherently unsafe”?
Brentford. Erik Johnson. Marketing Manager, Mercedes-Benz (England) Ltd
[It is true that Mercedes-Benz and Porsche have developed very sophisticated swing-axle systems over the years but even with these, many drivers report that although the handling is of a high standard there are times when these cars give them a feeling of uncertainty. Porsche are, of course, gradually replacing the swing axle of their competition models. The criticism was really aimed at the less highly developed systems such as those used on the Renault Dauphine, VW, Triumph Herald, etc., which do tend to suffer from the handling faults mentioned by Mr. Johnson. – M. L. T.
In many miles of fast motoring on the Continent and in England in 190, 220S, 220SE and 300 SL Mercedes-Benz I have no complaints. It is true that instability does result from the use of swing-axle i.r.s. but, realising this, Mercedes-Benz adopted their low-pivot layout and it does seem unkind of M. L. T. to criticise the swing axle as “inherently unsafe” unless he has proof of this from bitter experience on road or track, although he did not specifically associate his remark with the products of Stuttgart. –ED.]