Suspension Kit 36281824, Black

Ideally, springs only keep the vehicle at the desired height. Anything else is best handled by the shocks and the sway bars. These springs are made to work with Bilstein 8100 rear shocks and they make for the best combo available on the market: one full step above Fox and King offerings as the 8100 are external bypass shocks with a 2.65" body. Only Icon offers a comparable rear shock. BP51 is a much smaller piston as is the Fox TRD Pro shock: excellent for most uses but not top of the foodchain. So, with an 8100, these springs are perfect for they keep the factory spring rate and you can stiffen as needed from the shocks. The springs can also be used with well-tuned Fox or King or Icon shocks or with adjustable shocks from these brands. Even so, these springs are best used for vehicles that move faster or go in bigger rocks rather than for OZ-style expedition vehicles that always carry lots of weight. Such rigs would benefit from simpler setups with cheaper shocks and heavier duty springs. Light-duty applications on a lightly loaded vehicle would benefit from these springs with 5100s in order to keep comfort as good as it can be on a cheap shock but can also consider the Eibach 1" spring or the 1.5" Wheelers/Eibach T13 if they carry rear seat pax and/or more weight in the back. In sum, know your needs. This is a fantastic spring and the only one at this low spring rate. So the question is to choose the correct spring (and it is more important to choose the correct shock, springs are easy to replace anyway). For a stock-like rate lifted spring, this one is the only game in town.

Put these Bilstein 2.5” springs on my 2021 4Runner and I couldn’t be happier. The ride quality is way better than stock—firmer and more controlled without being harsh. The truck feels planted on the highway and so much more confident on rough roads and trails. The 2.5” lift gave me the perfect stance, just enough clearance for bigger tires without looking overdone. Install was straightforward, and everything fit exactly as it should. I was worried about losing comfort, but honestly it rides smoother than before and handles bumps with ease.

Got my Toyota lifted in the rear. Perfect stiffness for off-roading.

Update 10 June 2025: Months later and a 1.5" Bilstein 5100 w/ OME standard weight springs up front and it's still the perfect combo for me. I have a 45lb cargo carrier hanging off the back when I took the measurements in the picture. Perfect rake for 2000lb towing but almost seems level to the naked eye. Measurements are from the ground to the fender. 36" up front, 37.5" rear. Kit for the front was purchased from underdog suspension. Day 3 of 2018 4Runner TRD off road : measured 37-3/4 to 38" once settled. Factory front height of 34 3/4-35" means any 2" front lift will look good and maintain a mild rake (important for those who tow a 2500lb boat 10-20% of the time). Added Timbren SES to rear for dampening when loaded/towing. Great combination. I will do a follow up once the 5100's with OME coils are installed up front.

I followed some videos online and the installation for these was pretty straight forward. I don't have a lift, so I wasn't able to manipulate the axle quite enough to make the spring clear on it's own, but I compressed it just a little bit with a ratchet strap and was able to get the spring in place and release the strap. My I previously put in new Bilstein suspension (front and back) on my 2017 5th generation Toyota 4Runner Off Road Premium to handle the weight of a new bumper and skid plates. I did a 1-2" lift in the front, which made the rear squat just enough to be visible. These springs lifted the rear of the vehicle enough (probably about 2"-- maybe a smidge more with the stock bumper, no added weight) to get the stance of the 4Runner back to the way I like it. Riding empty (no load) on city streets, it's maybe a touch stiffer, but it's not noticeable. I have not taken it off road yet to see how it does on the trails, but I expect I'll be satisfied. Bilstein makes some good suspension parts, especially for 4Runners.

This product is trash. I would recommend it for anyone and when I told them it didn’t fit my vehicle they did not want to exchange it.

good ride height ! better than stock for sure !!

I recently installed Bilstein 5100s on the front of my 5th Gen 4Runner. I set them to 1.75” since I already had a 1” spacer in the rear. The back then sat about 1/2” shorter than the front so I replaced the spacer with these coils. The rear now sits about 1/2” taller than the front which is exactly what I wanted.