The Eibach Pro-Kit (part 6390.140) is a four-spring front and rear lowering set for rear-wheel-drive Infiniti G37 sedans from 2009 through 2013. The progressive rate Eibach springs replace the factory coils to lower the center of gravity and reduce squat, body roll, and nose dive. Owners on user forums report that the car feels more planted after installation, though one owner found the ride firmer than before, so impressions vary.
Choosing this kit over a budget spring makes sense because owners on user forums consistently steer buyers toward established brands over unknown ones, and the extra cost is small next to other suspension work. One owner reported less body roll in the corners and almost no nose dive under braking. Compared with H&R, Eibach is the milder option. H&R springs are much lower than Swift and Eibach, which are very mild. That makes it a better fit for a daily driver that needs sharper handling without a harsh ride. Buyers wanting more can pair these springs with the manufacturer's PRO-PLUS kit, which adds anti-roll bars.
Shoppers searching for G37 sedan RWD lowering springs, 2009-2013 G37 coil spring drop, or 6390.140 Pro-Kit install should note that this kit is listed for rear-wheel-drive sedans only. Lowering amounts vary by application, so confirm the exact drop for your car before ordering.
The manufacturer lists this kit for rear-wheel-drive sedans from 2009 to 2013. Owners on user forums have reported running the RWD springs on AWD sedans without problems, but since the manufacturer does not list AWD, confirm fitment before ordering.
Owners on user forums report that factory shocks on lower-mileage cars held up well after lowering. One owner with about 35,000 miles kept the stock shocks. Details vary, so inspect your shocks before installation.
Owners on user forums recommend an alignment after installation. Opinions on camber kits differ: some owners ran without one, while others reported needing one at larger drops. Confirm with an alignment shop.
Owners on user forums describe the rear springs as a manageable job, roughly 15 minutes per side once the wheel is off. The fronts are harder and require a MacPherson strut spring compressor, and one owner could not fit their compressor and had a dealer press the springs. Plan on a floor jack, jack stands, 17mm, 19mm, and 12mm sockets, and a torque wrench. Budget for a post-install alignment, and expect the springs to settle, which one owner measured at about half an inch in the first week.
