Is this how the Bilstein 185606 is supposed to look? (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Nov 22, 2022
Threads
28
Messages
98
Location
Texas
Installing the 185606 on the rear of my 40… Feels like the shock is compressed too much. Shock mounts are 17” apart and the 185606 is 22” long with a max compressed length of 14”. The bump stop is right at 3” from the bump plate. I feel like the shock will bottom out and sustain damage at some point. Haven’t removed the boot yet cause I might return them. Second pic is stock shackle vs what’s installed…I think the lift is about 1-1.5”. I understand the shock can be used on 0-2” lifts in the rear.
E7ADDBA9-9222-4BCB-9920-53569B03DCBD.jpeg

020D346B-5977-4830-B47B-416453711AD0.jpeg
 
looks like you ordered the rear shocks for the 75+ 40 - the shock mounted different location. All 4 shocks for the early 3speed 40s are same size front & back - 4 speEd backs are longer

i HATE the way these look - i got a correct size stainless hose clamp - cut the zip tie off and the boot now fits correctly. Your boot may just be sliding up the shaft - mine are now down near the decal
 
Last edited:
So ride height is at 17 pin to pin minus the bump stop to axle distance of 3 equals 14. You are at the compressed length of the shock if the shock was perfectly vertical. Keep in mind the bump stop measurement is vertical, pin to pin is not. The shock is not perfectly vertical, It's on an angle so it probably won't compress to it's limit of 14". The lift the shackle provides is 1/2 of the difference between the two. So if the long shackle is 1 1/2" longer over the stk one, then it provides 3/4" of lift. The vertical shackle is not helping how it rides. You really can't tell anything with the dust boot installed.
 
1F, 4 speed.

IIRC the front shock mounts are the same distance apart as the rear but the recommended shock is 062518 that’s 18.5” extended and 12” compressed. Feel the rears sustain damage when compressed and fronts sustain damage at max droop.
 
So ride height is at 17 pin to pin minus the bump stop to axle distance of 3 equals 14. You are at the compressed length of the shock if the shock was perfectly vertical. Keep in mind the bump stop measurement is vertical, pin to pin is not. The shock is not perfectly vertical, It's on an angle so it probably won't compress to it's limit of 14". The lift the shackle provides is 1/2 of the difference between the two. So if the long shackle is 1 1/2" longer over the stk one, then it provides 3/4" of lift. The vertical shackle is not helping how it rides. You really can't tell anything with the dust boot installed.
Good point about the shock angle. Didn’t think of it like that.

What’s the recommendation on the shackle?

Clearly new to the 40 game, I bought it recently and am trying to get it road worthy and I’m learning about 50 new things a day!
 
see how the later shocks were mounted at the bottom of the spring vs yours at the top of the spring - this could be somthing you need to check - hard to tell with the boot on - - for your mounting scenerio the front and rear shocks should have the same part number - not different
1671112674678.png
 
see how the later shocks were mounted at the bottom of the spring vs yours at the top of the spring - this could be somthing you need to check - hard to tell with the boot on - - for your mounting scenerio the front and rear shocks should have the same part number - not different
View attachment 3194065

It appears there's not much compression left on that shock compared to the distance between the bump stop and axle.
 
The distance of the front axle and rear axle mounting points are the same but rate of compression would be different for rear due to mounting angle.

The part numbers come straight from Bilstein for 0-2” lift.

Also, is the bottom mount in the picture part of the U-Bolt mounting plate?
 
yes they are - you can easily convert the older mount with later plates - i had a set of old conferr skid plates that adapted mine
supposedly this gives better articulation with the longer shocks
trailerbuild-027-jpg.190167
 
The distance of the front axle and rear axle mounting points are the same but rate of compression would be different for rear due to mounting angle.

The part numbers come straight from Bilstein for 0-2” lift.

Also, is the bottom mount in the picture part of the U-Bolt mounting plate?
If I remember right when I got my bilsteins, I called and they said they had 1 part number for all years and were unaware the rears had different mounting locations. I ordered the same shocks front and rear for my 1970 with 2.5” lift. Hard to tell from my pic but fair amount more showing and that side is compressed some (but it’s covered in snow).
5B7A5812-19DA-4903-977C-3EA4157021E1.jpeg
 
According to @bamelanc original post his shock compressed(14") and extended(22") dimension and his pin to pin(17") and bump stop dimension(3") indicates the shocks he has should work. The pin to pin measurement at ride height minus bump stop dimension equals how short the shock compressed length should be or a little less. To confirm this, using his bump stop dimension(3"), measure the 3" straight up from the lower shock pin, reference that point, then measure from that referenced point to the upper shock pin. If it is more than the 14" he should be golden. If its the same as the compressed shock(14") or less he can lower his bump stop so the shock doesn't bottom out. On my 75 40's I personally move my lower shock pin to the early FJ40 location, so the leaf spring protects the shock and pin. Trail riding thru the yrs, I found you want as much ground clearance as you can get and the bottom of the rig needs to be slippery as possible. I also flip my U bolts for the same reason. Even on my street 40 these mods are done. Someday it will see a trail. I have seen many vehicles on the trail that have broken shocks & pins and bent U bolts because of trail rash.
IMG00062-20110501-1150.jpg
 
My rear Bilsteins are same way, pb4ugo is spot on, if you got 3" to bump and you got 3" of shaft showing you are good as the shock tilt will travel a bit less, IIRC my shocks have exactly same amount of shaft as bump travel.
 
Installing the 185606 on the rear of my 40… Feels like the shock is compressed too much. Shock mounts are 17” apart and the 185606 is 22” long with a max compressed length of 14”. The bump stop is right at 3” from the bump plate. I feel like the shock will bottom out and sustain damage at some point. Haven’t removed the boot yet cause I might return them. Second pic is stock shackle vs what’s installed…I think the lift is about 1-1.5”. I understand the shock can be used on 0-2” lifts in the rear.
View attachment 3194024
View attachment 3194025

This may fall into the nitnoid category. You can mount these shocks in any orientation and they will articulate properly. However, the boot/rod is meant to be mounted “down”. It seems counter intuitive I know. But, you should see “weep holes” in the bottom lip of the boot. This allows any accumulated moisture to escape as the shock flexes. In your current mounting H2O that infiltrates the boot will accumulate at the base of your shock.

Or, you can sh*t can the boot all together with the shock/rod in the down position ref the pic above @Skreddy.

And least of all, you know the marketing guys at Bilstein, want anyone who peeks under your ride to be able read the label right side up. Just sayen. 😉
 
I ordered mine from summit with the part numbers below. My 40 is a 73 with a 3 Inch lift. Not sure if yours is lifted or not.

Screenshot_20221215_202342_Email.jpg
 
I re-installed shaft down. Cut the zip tie so the boot isn’t so compressed. We’ll see how they perform. Thanks everyone for your input.
 

Users who are viewing this thread

Back
Top Bottom