4” Lift K20 Bilstein 5100s too short.

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Grit dog

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Bought front, rear and new steering stabilizer. All part #s that match Bilstein 3-4” lift.
And presumably truck has a 4” lift since it has a 4” block sitting under OE leafs and it still has some rake to it (IE NOT 6” front springs).
Front shocks work but only have about 1.5” of down travel left which does not appear to be enough if the truck actually gets off road.
Rear shocks aren’t even quite long enough to bolt up at full extension?
And to top it off the one bushing on the steering stabilizer is too small for the factory mount.

All part #s are what’s listed every where for a 3-4” lift.
Even ORD lists same numbers for all.

Thinking maybe rear is short because it has extra leafs as an 8600gvw truck.
But the front and stabilizer issues are frustrating and not easily explained.

Anyone else run into this?
 

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yeppers
same prob, too short shocks. called the manufactor and told them they were too short (8" lift).
after sending them a pic of my susp, they sent me shocks for a 10" lift and (bonus) told me i could just keep the shorter shocks.
 

Grit dog

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yeppers
same prob, too short shocks. called the manufactor and told them they were too short (8" lift).
after sending them a pic of my susp, they sent me shocks for a 10" lift and (bonus) told me i could just keep the shorter shocks.
You called Bilstein direct?
Cause I Amazoned these and it’s too late to return now. Suppose I could enquire with Amazon about late return too.

Was it front and rear both too short?
However I rectify it I’ll have to measure everything and confirm.


Thanks for replying and confirming I’m not all ….ed up!
 

Grit dog

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So looking at the Bilstein catalog charts, it (surprising or not) appears that there is not a longer “direct fit” shock. Aka nothing for 73-91 GMs applications with greater than a “3 to 4 inch” lift.
Looking at 5125s there may be an option, as can get a stud mount top and eye bottom. Or eye to eye maybe using the old upper mounts, but will need to confirm bushings/sleeves are right size.

And at that I’m still skeptical the front shocks won’t get pulled apart if a guy actually flexed the front suspension past 2 inches of droop.

Never thought that literally all 5 shocks (including steering stabilizer) would not fit right or not fit at all….
Guess I should have just bought some rancho/skyjacker/pro comp lesser quality shocks. Cause now I’m sitting on $500 worth of shocks that will either never work, need modification to fit, or may not survive flexing the springs.

Kinda schitty….
Anyone with a 2” lift want to buy a new set of Bilsteins?

Edit: And the universal Bilsteins that "may work" have 12mm dia bushings and the OE on the truck are 14mm. What a monkey ****!
I might actually not buy Bilsteins again for anything...How f....ing hard is it to measure a couple trucks and make the right shock? There were like 10 kazillion squarebodys produced and still a couple kazillion of them on the road. Not like this is a rare application.
 
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CalSgt

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Dang Grit Dog... That sucks. What part numbers did you get, I included mine below for comparison. I am only running 3.5" re-arched springs in the front and 3" blocks in the rear and mine seem to fit. I did have to change out the bushing for the stabilizer but I ordered one for a dodge 2500 that had the right length and was prepared to switch out the bushings.


24-187084 (rear)​

24-187077 (Front)​

33-170794 (Stabilizer)​

 

89GMCJimmy

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Do you have stock and aux mounts?
I went from duals to single 5125’s I have a 3 1/2” lift
Top of axle tube to bump stop mount is 12” stock is 8 1/2”
 

89GMCJimmy

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This is how to measure
My old TC 2” springs lifted my front 3”
 

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89GMCJimmy

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One of these should work 5125 series
33-185590
21.5” ext
13.5 collapsed
8.1” travel
255/70 valving

33-230320
24” ext
15” collapsed
9 1/4” travel
360/80 valving

33-104652
28” ext
17” collapsed
11” travel
255/70 valving

33-230344
26” ext
16” collapsed
10” travel
360/80 valving
 

89GMCJimmy

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Sorry Just realized you have a k20 not sure what standard is but this might help
 

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RanchWelder

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scoots1 this thread has not been posted to since June 2022...
Your info is helpful though...
 

Grit dog

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Sorry Just realized you have a k20 not sure what standard is but this might help
Hey man, thanks!
I figured out I could get 5125s in the right length for front and rear. But still would have had to d!ck with the bushings. So I used the steering stabilizer on our 2016 Ram and was able to return all the shocks.
Went with some (way cheaper) properly fitting Skyjackers. They probably won’t last near as long, but hey, it’s a garage queen pavement princess anyways, lol. And they look better…and Skyjacker actually makes it easy to find the right shock application plug n play.

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Grit dog

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Dang Grit Dog... That sucks. What part numbers did you get, I included mine below for comparison. I am only running 3.5" re-arched springs in the front and 3" blocks in the rear and mine seem to fit. I did have to change out the bushing for the stabilizer but I ordered one for a dodge 2500 that had the right length and was prepared to switch out the bushings.


24-187084 (rear)​

24-187077 (Front)​

33-170794 (Stabilizer)​

Guess I never returned to this thread….
Those are the part numbers I bought as well. 2-4” lift iirc.
Fronts would bolt up but they were about 2” tops from full extension.
4” lift and thick leaf pack probably makes my setup need 1.5-2” longer shocks.
Rear axle I got 4” blocks and basically 1 ton springs (C6P truck). They wouldn’t even bolt up. Needed to be 4-5” longer to fit properly.

In short, the Bilstein applications are a generality and/or good for half tons only imo. Like I said above would have had to get 5125s to get the right length.
 

RanchWelder

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Cool, scoots1.
You brought it back and it got updated!
Came out nice Grit dog.

This is such good info.
Hopefully somebody will read this thread before they buy shocks, without measuring.
The look on your face must have been interesting, when the Bilstein's came up so far from the mounts... :secret:

What size wheels/tires are you using?
The tires look like US MIL treads?
 
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