2018 THOR Hurricane F53 18K chassis 190" WB – A huge Improvement! – Very Pleased To Parent Forum January 11, 2019 at 11:46 am #5023291565 mp23117Participant Installed SumoSprings front and rear on my RV. Even with previously installed rear bar track bar and front steer stabilizer, the significant improvment in handling with the new Sumos is amazing. Would recommend addition of Sumos to any F53 chassis. You must be logged in to reply to this topic.