My son purchased the 5100’s directly from Bilstein for me since he gets a discount through a friend’s shop. As a result, they didn’t come with the modified lower mounting hardware that ADD puts together in their kit and it took a bit of time to properly sort things out, especially on the rear lower mounts. Initially I felt the rears were too soft but it’s growing on me. Off-road they are great and feel very plush! I don’t know if I would like them on a LWB that is loaded however, and won’t be running them on my lifted 98. On road manners are just fine with little to no more body roll than stock but my electronically controlled shocks have had some wear (60k or so). The 5100 fronts feel like the middle position on the factory shocks and the rears feel like the soft position but more controlled.
This would certainly bear out in the numbers for compression and rebound from the shop manual and from Bilstein’s website. Mitsubishi spec’d rebound to be about twice that (2 to 1) of compression for the adjustable and non-adjustable shocks, whereas the front Bilstein are a closer to 4 to 1 and the rear 5100’s are just about 2 to 1. Overall the damping is softer on rebound and much softer on compression than stock or. Since the damping force between manufacturers is different (speed vs distance), the math is a bit beyond my back of the napkin abilities, so you can’t directly compare absolute damping force for either compression or rebound, but the ratios help a bit with insight into the comparison. Mitsubishi exerts a greater force (more distance in less time) to calculate their number than Bilstein, and also have higher absolute values for the resistive force the shock exerts when tested, but this would not be a linear relationship and I don’t know how to convert them to Bilstein number.
Suffice it to say they are both softer but more controlled. In addition, the 5100’s are a digressive rate shock meaning that the harder they are worked the softer they become, but in a very controlled way, unlike the way overheating and foaming feel. All in all I very nice addition. As a side note, the 4600 rears are still unavailable as Bilstein is retooling their manufacturing facilities and the demand for Pajero/Montero shocks of this era of vehicle is very limited. Koni would make some Heavy Tracks up for me but it was a 2-3 month lead time. If you want Bilstein and you want them now, 5100’s are your only option.
