Bilstein B8 5100 Adjustables for WK2

DogCatcher

New member
I was changing the brakes on our 2014 Grand Cherokee and noticed that the front driver strut was leaking. One of the rear shocks had previously blown out as well. It was replaced under warranty, but at this point I just want to replace the factory stuff with some Bilteins since I've always had good luck with their products.

I noticed that in addition to the typical B6 4600 series, they also have a B8 5100 series. These have an adjustable snap ring that sets the hight of the spring perch, allowing for adjustment of the ride hight in a few predefined increments. I took a couple of measurements and it seems like the 1.25" setting would probably just about level the ride.

Has anyone here used these? If so, what setting leveled the ride height out?
 

Shovel

Dreaming Ape
I don't have a WK2 so I can't comment on the application specifically - but I've used Bilstein HD(4600) and 5100's on several applications and here are the parts I think are relevant to what you're asking about:

The 4600 and 5100 are identical from a materials grade and performance perspective. For a given application they will be tuned a little bit differently with the expectation that the 5100's will go on a vehicle with a raised ride height and heavier tires, but in both cases the signature characteristic Bilstein seems to promote is their digressive profile which you're clearly familiar with.

Regarding the difference in ride height you can trust the increments they quote because you are reusing your existing springs with them, the only metric you're changing at static ride height is the distance between the lower spring seat and the bottom fixture - those are hard increments which aren't reliant upon the weight of the vehicle or the age of the springs. In other words if you want to level your vehicle you can measure how far from level it is now and determine the setting from that.

Noteworthy is that raising the ride height with this kind of strut assembly does change the behavior of the vehicle at the top of your suspension travel. While your static preload (or sag) on the spring doesn't change at normal ride height, the minimum preload is increased as you raise the vehicle so when your wheels transition from bearing weight to not bearing weight that can lead to some funny ride characteristics - I've seen others call it "like a pogo stick" and that's about how I'd put it too.

Hope that helps. Maybe somebody with a WK2 can comment more specifically for your application.
 

DogCatcher

New member
Noteworthy is that raising the ride height with this kind of strut assembly does change the behavior of the vehicle at the top of your suspension travel. While your static preload (or sag) on the spring doesn't change at normal ride height, the minimum preload is increased as you raise the vehicle so when your wheels transition from bearing weight to not bearing weight that can lead to some funny ride characteristics - I've seen others call it "like a pogo stick" and that's about how I'd put it too.
Thanks for the detailed response! This is exactly the kind of feedback I was looking for.

I live in Pennsylvania... we're not renowned for having the smoothest of roads, so I was curious if there would be any "quirks" introduced with this kind of adjustment to the ride, and it seems like this "pogo stick" behavior is something I'll want to look into a bit more. Thanks again!
 

Recommended books for Overlanding

Americas Overland - The Driving Handbook
by Donald Greene
From $20
Don't Go There. It's Not Safe. You'll Die.: And other mor...
by Jared McCaffree, Jessica Mans, Kobus Mans
From $19.99
The Longest Line on the Map: The United States, the Pan-A...
by Eric Rutkow
From $16.72
Road Fever (Vintage Departures)
by Tim Cahill
From $7.99
Motorcycle Messengers: Tales from the Road by Writers who...
by Lois Pryce, Mark Richardson, Carla King, Sam Manic...
From $9.99
FWIW, the B8 5100s are used widely in the Toyota world. I am expecting a set to be delivered today for my Sequoia. I went with these so I can retain the factory coil while still being able to adjust the height to match the rear OME coils I purchased. They can also be adjusted for bumper weight when adding an aftermarket bumper/winch.

I'm hoping to install these this weekend so I will follow up once I get them in.
 

Shovel

Dreaming Ape
it seems like this "pogo stick" behavior is something I'll want to look into a bit more.
Again this is not specific to the WK2 platform though I would expect the mechanics to be the same in all applications where the stock spring is reused and the lower spring seat is relocated up and down to produce lift.

On Ram 1500 trucks the Bilstein struts have 5 ring positions with the bottom two as the standard ride height for base trims and Outdoorsman/Rebel, respectively - all separated at a 0.7" ride height. Since the strut's fulcrum is around 2/3 of the distance from the chassis pivot and the ball joint that means the rings are roughly a half inch apart on the strut body.

So if you start with a base model 4wd truck you have the option of raising 0.7", 1.4", 2.1" and 2.8". On my own truck I have tried the top three settings and only found the pogo stick sensation to be frustrating at the top 2.8" setting, it wasn't really noticeable below that. Strange for such a small difference in distance to make a huge difference in ride character but there it is. On the highway they're all pretty much indistinguishable but crossing large speed bumps, or any kind of undulating terrain off pavement would reveal the difference right away.

Hopefully you can find somebody with the same vehicle to advise you on where the sweet spot is for that particular application. If you had a Ram 1500 I would strongly suggest sticking with the 2.1" or lower position but I would not expect identical results on other platforms. If you have no other source of information at all then I'd say the safe bet is to dial it back at least one notch from the highest one.. but in the end you'll have to be the one to determine what works best for you.
 

DogCatcher

New member
f you had a Ram 1500 I would strongly suggest sticking with the 2.1" or lower position but I would not expect identical results on other platforms. If you have no other source of information at all then I'd say the safe bet is to dial it back at least one notch from the highest one.. but in the end you'll have to be the one to determine what works best for you.
I did a little more measuring today and it seems like the 1.75" (top setting) would actually get me perfectly level with the rear... but based on this feedback and what I've read from other reviews, I think the 1.25" (second setting from the top) is probably going to be a safe bet. I went ahead and placed the order. I'll be sure to post my actual experiences here when I get them installed.

I'm hoping to install these this weekend so I will follow up once I get them in.
Definitely interested to hear your feedback as well. Thanks for the input.
 

DogCatcher

New member
I got the struts and shocks installed. The coil spring compressors I had were not up to the task of compressing the front springs quite enough. Instead of ordering a better tool, I just took the factory assemblies and the new struts to a local shop. $35 and a few hours later, I had two fully assembled front struts at the 1.25" lift height.

Getting the passenger side back in was easy as it seems the passenger CV axle is a bit longer than the driver side. On the driver side, I ended up sliding the CV axle out of the transfer case to get enough clearance to fit the slightly longer assembly back into place. I think I could have forced the assembly into place, but was really worried about tearing the CV boot...

Overall, I'm pretty happy with the new shocks/struts. At the 1.25" height, the ride is firm, but not too bouncy. I don't think it is fully settled yet, but I think it will come very close to leveling out the front and back height. I still need to get it aligned, but wanted to give it a chance to settle a bit before I do that.

I'm definitely more used to working on smaller cars (and usually, if I modify the suspension, it is making it lower). But overall, not a terrible install and I'm pretty happy with the results. This would definitely allow me to clear some slightly larger tires and I like the freshened up feel of the ride.
 
Top