Mercedes 722.9 Seven Speed Transmission Upgrade mercedes-benz-cls-class--218---2015-2018--cls-550-biturbo-esr2270978 SL 550 (R230) Stock Performance:

SL 550 (R230) Stock Performance:

0 (HP: 197 | Year: 06 > 10)

Front Splitter

Stock: 542 HP | 502 LB-FT

Mercedes 722.9 Seven Speed Transmission Upgrade mercedes-benz-cls-class--218---2015-2018--cls-550-biturbo-esr2270978 SL 550 (R230) Stock Performance:RENNtech Transmission Upgrade for 722. 9 Mercedes Seven Speed Transmissions. With increased engine performance it becomes necessary to further improve the drive line components, most importantly the transmission in order to ensure maximum power is transmitted to the drive wheels without transmission slippage. This can not be realized with software and only truly be accomplished by an internal mechanical upgrade to the transmission hardware. RENNtech