Onyxthecat

Hi all, I have had nothing but issues with my Arnott replacement suspension on my E500 wagon. Took a trip to Philadelphia and back to NYC and the passenger rear spring broke near the control arm mount. The spring sits on an aluminum mount that sits on the factory rear lower control arm since there's no other way to have a coil spring on there. I have already had to compensate the sag of the spring with a 3" spacer and some rubber inner spacers and it still sags which is unbelievable. I removed the spring and its so bent it will never sit straight again.
I know the BC racing coil over kit will fit the wagons but it requires the E350 rear lower control arms. I just need to verify if anyone knows if those control arms will bolt right up without modification. I will be ordering the kit through FCP Euro. Any help will be appreciated as I'm about to get rid of the car if I cant solve this.