FJ55 Shock Lengths

[Delancy]

I will not have the benefit, nor do I see any need, to cycle the suspension for accurate compressed and extended shock lengths.

I've searched, have spent time comparing OE specs to aftermarket options, and there's so many differences, thought I'd ask for y'alls input or experience.

Keep in mind, I don't have access to a Pig, at this time, nor did I have any way to estimate what "stock height" was, when I tried.

First.

Will a 2.5" shock even fit in the front OE tower?

Have no need to modify the tower for larger, but if larger is verified to fit, always a better option.

Second.

The '69-'74 Chassis and Body FSM specs:

**Front**
Compressed 13.31" (338mm)
Extended 22.36" (568mm)
Travel 9.05" (230mm)

Dampening at 1ft/sec (.3 m/sec)
Comp: 79lbs (36kg)
Rebound: 242lbs (110kg)

Front has a lower eye and upper pin bolt. The pin bolt length needs to be as short as possible to minimize cutting a hole in the inner fender to accommodate.

**Rear**

Compressed 13.31" (338mm)
Extended 22.36" (568mm)
Travel 9.05" (230mm)

Dampening at 1ft/sec (.3 m/sec)
Comp: 79lbs (36kg)
Rebound: 242lbs (110kg)

Rear is eye to eye.



I checked all model years and the part number for front/rear were the same, so the earlier FSM should, being operative, have the correct info.

In comparison, these lengths are around 2" longer than what Monroe lists as OE replacements and close to what OMEs chart shows they sent with the 55 specific kits, how ever long ago it was they produced.

According to the leaf manufacturer, the +2" requested, based on no additional weights, should net +2" to OE height....but I realize it's not a precise science.

I had figured I could add 2" to the OE extended lengths, work backwards to ensure the compressed was around an 1" longer than OE, but when discussing with shock producer, the first question asked was if the OE lengths I had provided (those above) had been adjusted for lift, already, because they were longer than any other product offering, so reason for asking for assistance.

 

[PabloCruise]

One approach may be to wait until lift springs are actually on the Pig and then measure stuffed and drooped, and then buy shocks?

 

[tucker74]

I don't know if this helps you or not, but it's the info I have on Bilstein's with a 2.5" lift:

55: F4-B46-0247 shocks for the front. These are for a standard height FJ60. The shocks have lengths of 526mm extended and 333mm compressed. I bought OMEB11 bushes to convert the large bottom eye to suit the 16mm pins.
I also installed the Bilstein shocks on the rear (F4-B46-0258/24-002585).

Tucker

 

[Delancy]

One approach may be to wait until lift springs are actually on the Pig and then measure stuffed and drooped, and then buy shocks?

Haha. TRUST ME, you don't want me to do that, since the thread may crash the server. That, and my other concern is that I'll repeat my past endeavors, cut out the leafs, link it on coil overs, if I wait until that point.

Here's the thing.

I'm "hoping" to drive it 800 miles home and won't have the time, based on how it's currently playing out, to cycle.

If I could've found a measurement that I could've translated as "stock height" be it, center of hub to wheel well or frame rail, even, this wouldn't be an issue, but no such data was located.

Regardless, you'd think it be as simple as adding the 2" to the OE extended length (again, assuming that the new leafs will add 2" to OE, though one could never tell.) and going from there, for the purpose of a DDer, not a wheeler.

 

[Delancy]

I don't know if this helps you or not, but it's the info I have on Bilstein's with a 2.5" lift:

It does.

For the record....

55: F4-B46-0247 shocks for the front. These are for a standard height FJ60.

The shocks have lengths of 526mm extended and 333mm compressed.

Is it possible that they measured differently in 1974?

Those are 2" shorter than the FSM measurements....but they're for a 2.5" lift.

(I don't do MM well, so..)

Extended 20.7"
Compressed 13.1"

I bought OMEB11 bushes to convert the large bottom eye to suit the 16mm pins. I also installed the Bilstein shocks on the rear (F4-B46-0258/24-002585). Tucker

Looking up.

 

[LAMBCRUSHER]

I suppose my rig is about 3+ stock as is sits, the doestch tecs are about 91/2" travel in front. I don't think they have ever hit the stops(full compression) but they have gotten close a few times; like the time at the range I was stepping off the shelf and let the passenger side slowly fall as much as it wanted- way stuffed/drooped; that let the magic smoke out of the passenger side cylinder, still need to address but o well for now...point being, you can use a shock for a stop to a degree, but not so well as a limiter from what my experience tells me. more spring means more droop. compression will only ever go so far, but droop can straight drop for as much as the springs and shackles will allow...seems to me that the 9 1/2 travel in front is at least 2 short, which means a 12" shock which will be about 16 compressed(roughly) which means that the shock needs to be mounted at least 3" higher at the top or 3" lower at the bottom or a mix of both to allow full shock compression to put suspension compression to about 1" further from the stops with the lifted springs( based my 3+ stock suspension...)...best bet is to do as Pablo says and wait to cycle the built and loaded suspension and wait another week for the shocks(unless you're like me and learn things like this by doing it anyway only to find that you shoulda woulda coulda....) just trying to help

 

[PabloCruise]

I'll say that I offered that advise after lifting my 40 and I ordered up a set of Doetsch Tech that "should" have worked based on my calculations.

So then I got to pay for return shipping and then wait for another order to ship...

 

[Delancy]

(unless you're like me and learn things like this by doing it anyway only to find that you shoulda woulda coulda....)

, but I've learned....









No choice on the 80, since using magical coils and arms. Didn't think necessary on the Pig considering usage and that the OE specs were available, but not wanting to repeat my many previous failures.

Not currently looking at an "off the shelf" option, but shocks specific built. There are more questions than I can't yet answer, beyond travel specs, being the bushing ID and width, sleeve ID and length, or the dimension the front upper pin bolt can protrude that won't require inner fender holes.

 

[Delancy]

Anyone possibly know:

1. Shock bushing through hole ID diameter and width?

(Or shock stud OD and length?)

2. Do most have a sleeve over the stud, through the bushing?

3. Front shock pin bolt length before contacting fender?

I can answer none....only shocks I have were incorrect, evidenced by the lower eye coming loose on a rear.

 

[LAMBCRUSHER]

tomorrow...it's dark out there

 

[Delancy]

Think it's answered.

A1 30mm OD
A2 25mm OD
B 16mm ID
C 35mm L
D 6mm

Upper Front Shock Pin Bolt bushing

A 25mm OD
B 10mm ID
C 15mm L

On to worrying with compressed/extended lengths and their implications on smooth bodied 2.0s...

 

[LAMBCRUSHER]

remember, you can use some shocks as stops, but none should be used as droop limiters. your total potential droop should be what determines the shock extended length...

 

[PabloCruise]

I'm "hoping" to drive it 800 miles home and won't have the time, based on how it's currently playing out, to cycle...

If the plan is still to drive it home, let me know when you are picking up from Robbie. I'd love to drive down in the Pig and meet you, and see your Pig!

 

[Delancy]

remember, you can use some shocks as stops, but none should be used as droop limiters. your total potential droop should be what determines the shock extended length...

I've always ran both beyond the limitations of the suspension, be it droop or stuffed, but have always ran 2.5s with resi's.

Don't see a need for in the application, but based on what I know, being measured full extension with the new leafs and what the compressed aftermarket and OE lengths are listed as, there's no way to build a 2.0 emulsion, since that's +9" of shock travel.

Have no means to cycle, nor is it warranted, since she ain't gonna see much but a gravel road.

Have no means to establish length at ride height...or by the time it's on back on all fours, with the drivetrain in, won't have the time to wait on shocks.

Shouldn't be the complicated, quote frankly, but don't want to be hitting the shock stops driving around town.

Verbose way to say....

It's hard to calculate an equation when you only have one number.

If the plan is still to drive it home, let me know when you are picking up from Robbie. I'd love to drive down in the Pig and meet you, and see your Pig!

My world is so jacked up, right now, I can't plan past tomorrow. Having a hard time finding the heart to "plan" builds, or even enjoying sitting on the sidelines and watching commissioned projects unfold.

The rescan in two weeks will dictate the balance of treatments, but if the anticipated results are favorable, still looking at two more months of chemo. Never had intentions of leaving town before those were complete, but I've recently began to understand that it won't be over then, even if all is gone....

Like it's sucked the soul out and can only pray that'll return very quickly after treatment is complete and eradication confirmed.

Handled chemo like a champ, but it's taken a toll in the last few weeks that are killing us to witness.

In the words of the commercial...."if you've healthy children, give 'em a big hug today."

Nothing more defeating than realizing how I took that for granted.

Edited: in other words, if Robbie finishes in November, it may be transported home. He's no space to store until next spring and hoping it's completed before then.

 

[PabloCruise]

Dude, I am the biggest dumb-a$$ when it comes to taking my blessings for granted!
Even if your kids aren't healthy, give them a hug!
Let me know if I can do anything to help.

 

[LAMBCRUSHER]

if not jumping, and the biggest concern is bottoming out, then just get those shocks that spec 2" short on extension. you'll get damping without worry of hitting the stops, but you'll have to be careful articulating it...

 

[LAMBCRUSHER]

1. LAMBCRUSHER, Feb 17, 2010EditDeleteReport
   #15+ QuoteReply
   
   
2. 
   LAMBCRUSHER
   Messages:
   4,590
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   Fronts are 8180. 13" compressed, 21.5" extended. Rears are 8277: 14.5" compressed, 24.5" extended. Bit of grease on the poly bushings and they go right on. They have integrated bumpstops . I have the steering damper and included hardware, but won't put it on till I do the center arm in the next couple of weeks....
   LAMBCRUSHER, Apr 27, 2010EditDeleteReport
   #16+ QuoteReply
   
   
3. 
   PabloCruiseSILVER Star
   Messages:
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   Location:
   Northern Colorado
   
   Let us know how you like them!
   
   Are the fronts fit the factory shock mount?​

from this>>>https://forum.ih8mud.com/threads/how-shocking.358495/


it seems to me as tho, based upon the numbers you have posted regarding factory spec, the bastids at DT specd me stock sized front shocks even tho they knew I was lifted...the rears they specd me tho seem to jive with a lifted suspension...I stated already that I thought my fronts were too squat, this seems to esplain that...HTH

 

[J Mack]

It's hard to calculate an equation when you only have one number.

Kurt @ Cruiser Outfitters was able to calculate my shock length and hardware requirements over the phone and and everything worked as planed.
Might be an option....

My world is so jacked up, right now, I can't plan past tomorrow.

If any help is needed, I'm offering.

 

[Delancy]

Come up with 23" extended, 8" stroke all possible with emulsions, so 15" compressed.

Anyone sees any issues with, please lemme know..

 

[Delancy]

Y'alls post didn't post before the one above. Reading back through now.