Abstract: Taking lower control arm as an example, a program spectrum compiling method for automotive components is introduced. Based on pseudo damage analysis and statistical analysis, combined with structural low loading strengthening property, a spectrum compiling method considering the strengthening effective loads is put forward, which overcomes the deficiency of the traditional methods, of which only the damage effect of low amplitude loads is considered. Meanwhile, referred to the equivalent damage rule between damage loads, the equivalent strengthening rule between strengthening loads is explored. By transferring the strengthening loads to the most effective level, the bench tests see the total cycling blocks decline sharply under home-made specification. It proves that while deleting the useless loads during the spectrum compiling process, the strengthening loads’ influence should be taken into account. Moreover, the real service condition of auto components by simulation can be faster and more real, and it is significant to predicate the failure mode of durability tests and to estimate service life of auto components more accurately.

Key words: auto component;program load spectrum;load below the fatigue limit;durability test;lower control arm