Oh my - FOX Shocks

Measuring between the eyes and then subtracting the gap between the bumpstops I have roughly:

Rear: 19" (measuring only half the rubber)
Front 14.5" (rubber fully removed)

Is that to say that a shock with a collapsed length longer than 14.5" or more, will bottom out as the bump-stop makes contact? I must be misunderstanding your numbers, because that is shorter than the FOX shock spec posted earlier.
 
Is that to say that a shock with a collapsed length longer than 14.5" or more, will bottom out as the bump-stop makes contact? I must be misunderstanding your numbers, because that is shorter than the FOX shock spec posted earlier.

Yes, that is correct (based on my very rough measurements). It is shorter than the Fox spec which is interesting. I've always removed the squishy rubber bumpstops (known as a jounce) for measurements since they 1) can squish 2) can fall out or deteriorate so they shouldn't be assumed. But maybe Fox knows something about the fronts that I don't know.

Has anyone ever loaded the front or rear suspension to the point of squishing the bumpstops? I'm wondering if the factory shocks bottom out before they hit...? I can't imagine Ford doing that though and I'd think we'd be seeing more broken shock mounts. Even pulling a heavy gooseneck, I've only seen some markings in dust on my rear bumpstop pads as evidence that they touch, but never a sign of them compressing.
 
Yes, that is correct (based on my very rough measurements). It is shorter than the Fox spec which is interesting. I've always removed the squishy rubber bumpstops (known as a jounce) for measurements since they 1) can squish 2) can fall out or deteriorate so they shouldn't be assumed. But maybe Fox knows something about the fronts that I don't know.

Has anyone ever loaded the front or rear suspension to the point of squishing the bumpstops? I'm wondering if the factory shocks bottom out before they hit...? I can't imagine Ford doing that though and I'd think we'd be seeing more broken shock mounts. Even pulling a heavy gooseneck, I've only seen some markings in dust on my rear bumpstop pads as evidence that they touch, but never a sign of them compressing.

OE shocks are usually conservative, meaning they are far from bottoming out before the bump stop does. Bottoming out a shock is the worst thing you can do to a shock. They will die quickly. When you look at the compressed length of a FOX 2.0, or a Bilstein 5100 they both are under 14" collapsed length, but I also can't see FOX listing a shock for 0-1.5" if it could potentially bottom out. So that 14.81 should be safe. Post #50 makes it sound like the axle bump stop and shock bumper make contact at about the same time. Could be super close to bottoming but doesn't 🤷🏻‍♂️.
 
Some of the thoughts I'm thinking have been addressed. Shock "collapsed" length is key. Previous pictures show shocks at a point where physically cannot compress any further. Is that the same as when mounted on the truck?? I doubt it...BUT...it's key as what has been said.
The suspension travel to the point where it's contacting bump stops tends to be "the limit" of travel. So what's the eye-to-eye (ETE) mounting point of the suspension measurement(s)? Not the shocks but the suspension.
If that ETE measurement is LESS than the "fully" compressed length of the shock off the truck you might have a problem.
If the ETE measurement is MORE than the "fully" compressed length of the shock then you should be good to go. Does that make sense??

See Post #22 for the pictures. The rear shocks tend to not have issues. The front shocks can be the worst.

Some of this goes hand in hand with lift kits. There's a reason they provide front bump stop spacers to move them lower (hence closer to contacting the axle on full suspension travel).
 
Note that the section between the green lines is made of rubber. This might explain the appearance of being fully collapsed in the picture, as there's still about 5/8" of rubber compression available.

With the stock Tremor coil springs, my front shock shafts were clean occasionally (shock wipers after a significant impact) and the joust pads showed imprints from the bump stops. However, I never experienced a jarring hit that you'd typically get without any rubber in place (the kind that can destroy shocks).

*I would get the measurements you're looking for to confirm, but I've since swapped to F450 coil springs and added a Rough Country 1.5" Leveling Kit, achieving about a .75" lift up front. Therefore, it wouldn't be a direct comparison to the old Tremor springs


rubber.jpg
 
Thanks for all the help. I'm not one for getting too deep but the information helps people make better choices or just have the best info possible.

Any "extra" travel from rubber compressing might be mute. If 1/2" is the difference in blowing out a shock then the answer is already known.
 
FYI - Fox assumes that rubber bumper isn't on their shocks for their listed measurements. Because it can compress.
 
My Fox 2.5 DSC rears arrived and I put them on today. It already seems to have better behavior through ruts than the OEM shocks. It wanted to bounce around a lot before. Jumping in the back of the bed also is noticably less bouncy. It just soaks the impact without secondary bounces. This is what I expected since I have the same on my Jeep. I can't wait for the fronts to arrive. I'll be putting a lot of highway miles on next week to go see the eclipse so we'll see if my wife notices anything different. 🤫
 
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