Bilstein front 5100 facts , just say NO

tommudd

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Anyone thinking or wanting to use the Bilstein 5100 adjustable front shocks , think again
If you do want to use them, not sure why but,.....
You should not install them any more than sitting at the 0 mark, that is it
Any higher and it will create a disaster , degrading the springs within a few months
It preloads the springs which is very bad much like cheap spacer lifts do
These shocks should of never been built in the first place
4600s are cheaper , are the same internally , and are built for the KJs/KKs to keep the same spring perch at stock distances
Jeepinjarhead and I have discussed this and just today I seen a discussion suggesting someone use them
Please do not , unless you want to spend the extra money , set them at 0 just to say you have them
Questions ?
 
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lfhoward

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This is good to know, Tom. I wonder if the reason people are interested in this is because they want something like the JBA adjust a struts that are no longer made anymore. Do you have a pic? At least that is what I am visualizing in my head.
 

tommudd

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This is good to know, Tom. I wonder if the reason people are interested in this is because they want something like the JBA adjust a struts that are no longer made anymore. Do you have a pic? At least that is what I am visualizing in my head.
Yes people are thinking they can say install 927 front springs then these shocks and then gain some extra height. They are adjustable in height from 0-to 2.5 or so
and having the 5100 designation thinking they are a much better shock
rear 5100s are better but not these
but when you look at specs they are basically the same
See this issue on the front 5100s coming up more and more so thought it was time to keep info straight
And not have people spending money needlessly
 

tommudd

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tommudd

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First picture you can see the rings, where as the JBAs are on top and more adjustability , work sort of the same
Bottom picture shows it together ready for the spring

For numbers
the 4600s are 24-139168.....yes
for 5100s they are 24-282642 .....no
so you do not mix them up
 
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James Akemon

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Yes people are thinking they can say install 927 front springs then these shocks and then gain some extra height. They are adjustable in height from 0-to 2.5 or so
and having the 5100 designation thinking they are a much better shock
rear 5100s are better but not these
but when you look at specs they are basically the same
See this issue on the front 5100s coming up more and more so thought it was time to keep info straight
And not have people spending money needlessly
We can tell this info all day long, most won't listen. **** they don't listen when told the bad effects a Daystar rubber isolator lift causes.
 

tommudd

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We can tell this info all day long, most won't listen. **** they don't listen when told the bad effects a Daystar rubber isolator lift causes.
Yes that is so true
But I can't help myself
Been preaching the Gospel of OME for over 17 years for the KJs and still do it
some listen, some learn the hard way LOL
 

mike.bannister

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I'm not seeing how the preload from using the upper perches (0.5 - 2.5" of lift) on the 5100s would wear the springs out early. Yes, when the tires are off the ground the spring is compressed and is under a greater load than w/ the perch set at 0. But 99% of the time the vehicle has all 4 tires on the ground, and as long as the vehicle weight hasn't changed the the spring is compressed the exact same amount as w/ factory shocks. Since it's lifted the suspension angles are different, but that should wear out CV joints etc. faster, not the springs.
 

Johnny O

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Don’t need the perches when doing the spring lift. Put the clip on the bottom one.

Though OME is tops. I’m running a pair on wifey’s only because they were deeply discounted and were still waiting on her nitrochargers.

Suspension was stacked all around when we bought hers so it was a necessity situation. Couldn’t wait any longer. Downside is I basically get to do the work a third time to get the 90009s in.
 

tommudd

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I'm not seeing how the preload from using the upper perches (0.5 - 2.5" of lift) on the 5100s would wear the springs out early. Yes, when the tires are off the ground the spring is compressed and is under a greater load than w/ the perch set at 0. But 99% of the time the vehicle has all 4 tires on the ground, and as long as the vehicle weight hasn't changed the the spring is compressed the exact same amount as w/ factory shocks. Since it's lifted the suspension angles are different, but that should wear out CV joints etc. faster, not the springs.
IT PRELOADS THE SPRING , PERIOD
SPRING IS NOT COMPRESSED SAME AS STOCK,
NEED TO STUDY UP
 

WheelNut

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I'm not seeing how the preload from using the upper perches (0.5 - 2.5" of lift) on the 5100s would wear the springs out early. Yes, when the tires are off the ground the spring is compressed and is under a greater load than w/ the perch set at 0. But 99% of the time the vehicle has all 4 tires on the ground, and as long as the vehicle weight hasn't changed the the spring is compressed the exact same amount as w/ factory shocks. Since it's lifted the suspension angles are different, but that should wear out CV joints etc. faster, not the springs.
You're certainly not wrong.
(What follows is me repeating what you already said, but with some additional thoughts sprinkled in)
In a static state the spring is compressed the same amount whether or not there is a spacer under the bottom of the spring, or the spring perch is moved up. In this state the UPPER spring mount moves up commensurately with the lower, so the distance from the lower spring perch to the upper spring perch is the same (This assuming the shocks have not been fully extended by the repositioning of the lower spring perch). The only geometrically significant difference is that at full compression there is less space for the spring, so upon compression the spring is compressed more than what is possible with the factory setup. Perhaps this over compression is what causes the accelerated sagging of the spring. It seems to be common knowledge amongst the learned here that the OEM springs are highly susceptible to sagging, so anything that stresses them beyond what the OEM geometry subjects them too must increase that sagging process.

That being said the minimum amount of compression the spring is under is always higher (higher preload) when the lower perch is relocated because the length of the shock is unchanged, so that probably adds even more to the problem.

Prepare hit the double caps lock key Tom, hahahah
 
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tommudd

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Don’t need the perches when doing the spring lift. Put the clip on the bottom one.

Though OME is tops. I’m running a pair on wifey’s only because they were deeply discounted and were still waiting on her nitrochargers.

Suspension was stacked all around when we bought hers so it was a necessity situation. Couldn’t wait any longer. Downside is I basically get to do the work a third time to get the 90009s in.
Why not go with the 4600s , cheaper and internally the same
 

tommudd

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Im going to stop posting anything that will cause excessive wear or be an issue down the road for Liberty owners
Try to help them and what do ya get back ,.....................GRIEF
Heck Im on my 4th wife, I already have enough grief
( no actually I get along with all my ex's really well )
But ,..........................................
 

James Akemon

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Im going to stop posting anything that will cause excessive wear or be an issue down the road for Liberty owners
Try to help them and what do ya get back ,.....................GRIEF
Heck Im on my 4th wife, I already have enough grief
( no actually I get along with all my ex's really well )
But ,..........................................
As you stated to me, some will listen.
 

njpaulkj

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5100's are only good at the lowest position with STOCK length springs or an equivalent stock length replacement. 100% agreed. It is this combo or anything else, NOT "Oh I will use the 1.5 inch higher spring perch PLUS a longer lift spring!" **** NO!!

The cheap *** zinc plating on the 5100 ***** *** anyway. It is not chemical conversion coating or anodizing on aluminum. It is a steel body with an even. but thin cheap *** zinc plate job. Bleah! You must wipe them down, move the boots, mask off the shafts and spray them with catalyzed clear coat or suffer cheap ****** looking shock bodies (sort of like the cheap *** galvanized dip job on oem Chrysler/Mopar mounting bolts...rust ahoy)

Just use the 4600, save $40, and have beautiful, classic Bilstein (like Koni!?) yellow shocks.
 
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