Bilstein 5100's - notes


StG58

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Some notes on Bilstein 5100 shocks.

Bar Pins - Bilstein bonds the bar pins to the bushing on the 5100. You can push the bar pin and the bushing out of the shock, but that bar pin is NOT coming out of the bushing. If you want to run BPE's, see the note below on replacement bushings.

Bushings - Manufacturer bushings are available for a nominal cost. I found them for as cheap as $3 each online. Bilstein makes both urethane and rubber bushings as replacements. The rubber bushings have a steel sleeve molded in and are double tapered (like an hour glass). Do yourself a favor and get the rubber bushings. Sometimes a shock bushing gets abused and worn, needing replacement, while the shock is still in good shape. Here's your solution.

Running a Bilstein upside down - The jury is still out on that one. Some places say that the valving doesn't work correctly when you flip them, some places say it's not a problem. If anyone runs Bilstein 5100's flipped, please chime in with your experiences. Bilstein recommends not running their shocks upside down on some pages of their site, and says it's not a problem on another page. That's for the same part number by the way. They do make shocks that are essentially identical to the TJ rear shocks with the rod down though. Haven't looked for similar front shocks yet.

Boots - I run the boots, have for years, and have never had a problem with it. With that said, boots or no boots is a choice that needs to be made. Reasonably speaking, you probably want to take them off. That means a little cutting with a sharp knife on the back shocks and wrestling with them on the front. Shock boots are probably more decorative than functional, and are a stylistic leftover from the '80's. If you do run shock boots, don't zip tie the boot to the shock.

DON'T try to run the gas charged Bilstein steering damper. That thing will mess you up the instant it is installed.

A correctly installed Bilstein 5100 has the lettering right side up. You can read it without standing on your head.

Understanding Bilstein Valve Ratings
Damping forces of Bilstein valvings are measured in Newtons at a velocity of 0.52 meters/seconds (approximately 20 inches/second). The ratings shown correspond to those measurements; rebound force is the first number, followed by compression force (rebound / compression). Conventionally, the ratings are written as one tenth the damping force in Newtons.

EXAMPLE: Valve rating: 275 / 78
Rebound force is 2750 Newtons at 0.52 m/s
Compression force is 780 Newtons at 0.52 m/s
Higher numbers mean higher (firmer) damping forces. For example, 360/80 has more control (is firmer) than 275/78, while 170/60 has less control (is softer) than 275/78.

Digressive shocks
In a Digressive shock, as shaft speed increases, damping forces increase but at a decreasing rate. In other words the shock is stiffer hitting a bump at a higher speed than at hitting the same bump at a lower speed. But, the amount of stiffness doesn't increase at the same rate as the speed increases. Example: Hit a bump at 5mph and the shock is stiff. Hit a bump at 10 mph and the shock is 2x stiff, hit a bump at 15 mph and the shock is 2.5x stiff, hit the bump at 20 mph and the shock is 2.8x stiff.

Digressive shocks can provide low-speed damping control without being unreasonably harsh on rough surfaces. Digressive shocks allow separate damping and rebound rates.

The TJ shocks are made in the USA.

Flipped means rod down in the information below.

TJ part numbers:
B8 5100 - Shock Absorber
Part Number: 24-186810
Position: Front
Descriptor: For Front Lifted Height: 0-2"
Collapsed Length (IN): 13.06
Extended Length (IN): 21.18

Part Number: 24-185257
Position: Front
Descriptor: For Front Lifted Height: 3"
Descriptor: With Short Arm Lift Kit
Collapsed Length (IN): 14.88
Extended Length (IN): 24

Part Number: 24-188180
Position: Front
Descriptor: For Front Lifted Height: 3.5-4"
Descriptor: With Short Arm Lift Kit
Collapsed Length (IN): 14.98
Extended Length (IN): 24.63

Part Number: 24-185929
Position: Front
Descriptor: For Front Lifted Height: 3.5-4"
Descriptor: With Long Arm Lift Kit
Collapsed Length (IN): 14.98
Extended Length (IN): 24.63

Part Number: 24-187190
Position: Front
Descriptor: For Front Lifted Height: 4.5"
Descriptor: With Long Arm Lift Kit
Collapsed Length (IN): 16.51
Extended Length (IN): 26.5

Part Number: 24-185943
Position: Front
Descriptor: For Front Lifted Height: 5-6"
Descriptor: With Long Arm Lift Kit
Collapsed Length (IN): 16.97
Extended Length (IN): 28.44

Part Number: 24-186827
Position: Rear
Descriptor: For Rear Lifted Height: 0-2"
Collapsed Length (IN): 12.81
Extended Length (IN): 20.08

Part Number: 24-185264
Position: Rear
Descriptor: For Rear Lifted Height: 3"
Descriptor: With Short Arm Lift Kit
Collapsed Length (IN): 14.63
Extended Length (IN): 23.07

Part Number: 33-185514
Position: Rear
Descriptor: For Rear Lifted Height: 3.5-4"
Descriptor: With Short Arm Lift Kit (flipped)
Collapsed Length (IN): 15.41
Extended Length (IN): 25

Part Number: 33-185934
Position: Rear
Descriptor: For Rear Lifted Height: 3.5-6"
Descriptor: With Long Arm Lift Kit (flipped)
Collapsed Length (IN): 15.41
Extended Length (IN): 25

Just a note on my installation. I installed 5100's when I installed the H&R springs. The springs gave me just about 1-1/2" of lift. I did not need to adjust my bump stops after installation for the springs, the shocks or my 31x10.50R15 KO2 tires on Grizzly 15x7" wheels. The installation worked out rather nicely and works great together on the trails I run. YMMV
 
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Chris

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So I take it you're liking them so far? I've got a few years on mine and still love them as much as I did when I first installed them.

These are good notes though, that's for sure.
 
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StG58

StG58

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Lovin' mine. They work exceptionally well for what I use the TJ for. I've got some more notes to add, an explanation of digressive valving and how it works, shock ratings and that sort of thing. Lot's of information out there but you have to dig a little. Eventually, I'll add part numbers for both the normal and inverted shocks for a TJ.
 
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Chris

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I didn't even realize they had the option of normal and inverted shocks. Interesting!
 
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StG58

StG58

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Yup, dig around a little on the Bilstein site, and they will even build you a custom shock with custom valving. Don't even want to know how much that would cost. They have rebuildable reservoir shocks that they will customize the valving for. Custom shocks for long arm TJ setups. Lots of cool stuff. Custom compression and rebound rates where you can select the compression rate and the rebound rate separately.

One thing I've noticed with my set of springs and shocks. The harder I push them, the better they work. With an SE, I'm not a fast mover by any means. But the combination of the H&R springs and 5100's works great hauling ass down a rough road. They work better at 30 mph than they do at 15. Everything just smooths out and runs. The tires stay planted too.
 
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Chris

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Very cool! Yes, I'm sure Bilstein will build you whatever you want. They'll just charge you an arm and a leg for it. Of course, none of us would ever need that, unless we were building some sort of dedicated, monster trail rig.

It's good to hear that combo is working out with you. Blaine and Jerry hate the Bilstein shocks and say they ride like crap (can't remember their exact words, but that's close enough), and I highly disagree. My Bilstein shocks ride wonderfully. My wife always comments that the Jeep rides very smooth. I agree with her, you really would think it rides better than stock!
 
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StG58

StG58

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Very cool! Yes, I'm sure Bilstein will build you whatever you want. They'll just charge you an arm and a leg for it. Of course, none of us would ever need that, unless we were building some sort of dedicated, monster trail rig.

It's good to hear that combo is working out with you. Blaine and Jerry hate the Bilstein shocks and say they ride like crap (can't remember their exact words, but that's close enough), and I highly disagree. My Bilstein shocks ride wonderfully. My wife always comments that the Jeep rides very smooth. I agree with her, you really would think it rides better than stock!
Blaine and Jerry are operating in different conditions. There was something about driving over a dime and being able to tell if it was heads or tails. I get it. That's not my experience, but who am I to argue with those guys?

I do know that the combination of H&R springs, Bilstein 5100's and the KO2's absolutely rocks for the conditions that I wheel in. I can blow down the trail at +10-15 mph more than stock with a better ride than stock. That's something. I know you like OME, but if you are not going to 32" tires or taller, this is a good setup. A very good setup. And it's cheap and sturdy.
 

Chris

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Blaine and Jerry are operating in different conditions. There was something about driving over a dime and being able to tell if it was heads or tails. I get it. That's not my experience, but who am I to argue with those guys?

I do know that the combination of H&R springs, Bilstein 5100's and the KO2's absolutely rocks for the conditions that I wheel in. I can blow down the trail at +10-15 mph more than stock with a better ride than stock. That's something. I know you like OME, but if you are not going to 32" tires or taller, this is a good setup. A very good setup. And it's cheap and sturdy.
I don't know man... The pothole ridden roads up in Portland (which I did A LOT of driving on) are probably some of the shittiest city streets in the country, and my TJ handled them like a champ with no harshness whatsoever.

I only like OME so much because it's one of the few lift (aside from Currie and RC) that I have experience with. I'm sure I'd be raving about your setup too, if I had it.

Same thing with the Duratracs, haha.
 
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RustyCage

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Some notes on Bilstein 5100 shocks.

DON'T try to run the gas charged Bilstein steering damper. That thing will mess you up the instant it is installed.
@StG58 curious why you say this? Just ordered the 5100s for my '01 TJ. Pairing with the stock springs and 2" pucks. I'm running the exact same tires and wheels as you. ZJ tie rod upgrade is on the list just as soon as I can get to the junkyard. Will replace the steering damper at that time. What do you like then if not the Bilstein? Thanks.
 

Rob5589

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@StG58 curious why you say this? Just ordered the 5100s for my '01 TJ. Pairing with the stock springs and 2" pucks. I'm running the exact same tires and wheels as you. ZJ tie rod upgrade is on the list just as soon as I can get to the junkyard. Will replace the steering damper at that time. What do you like then if not the Bilstein? Thanks.
You don't want a gas charged damper due to it constantly try to expand. A 50/50 valved hydro damper is what you want. Don't overthink (over pay) for a damper. This Monroe is all you need https://www.amazon.com/dp/B000C53XRK/?tag=wranglerorg-20
 
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jjvw

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@StG58 curious why you say this? Just ordered the 5100s for my '01 TJ. Pairing with the stock springs and 2" pucks. I'm running the exact same tires and wheels as you. ZJ tie rod upgrade is on the list just as soon as I can get to the junkyard. Will replace the steering damper at that time. What do you like then if not the Bilstein? Thanks.
A gas charged steering damper will want to extend and steer the Jeep. A hydraulic damper is the better choice for this application.

A $25 Monroe is really all anyone needs.
 

Lj the TJ

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Hey gang,
I hears lot of talking how great the Bilstein 5100 are for stock height applications but I was wondering if there’s a difference in the part numbers noted on this post for a zero inch lift and other ones I seen on Amazon besides the blue or black boot option. Don’t won’t to make the wrong purchase. Thanks in advance.

05B160D0-15EA-468C-88E2-021CAE2F5838.jpg
 

Chris

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Hey gang,
I hears lot of talking how great the Bilstein 5100 are for stock height applications but I was wondering if there’s a difference in the part numbers noted on this post for a zero inch lift and other ones I seen on Amazon besides the blue or black boot option. Don’t won’t to make the wrong purchase. Thanks in advance.

View attachment 180917
Look for those part numbers on the Bilstein website and they will tell you what lift height they are meant for.
 

Lj the TJ

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They check out. It appears as if they’re both made for my application and not to mention on sale none the less. Thanks for the heads up. You sir have saved me 60 bucks.

3915E42B-33B5-484C-9620-A70224CAFC81.png
 

jjvw

Everything is great. No issues.
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Hey gang,
I hears lot of talking how great the Bilstein 5100 are for stock height applications but I was wondering if there’s a difference in the part numbers noted on this post for a zero inch lift and other ones I seen on Amazon besides the blue or black boot option. Don’t won’t to make the wrong purchase. Thanks in advance.

View attachment 180917
Keep reading. Great might a generous statement, unless your are ok with a jittery ride.
 

pagrey

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You might look into the 4600 as well. That is the shock for a stock TJ, the 5100s are longer even though they are advertised as 0-2" the 4600 is actually the stock size.