Fox 4" - 6" External Res + 3" Coils

Anyone running this combo?
Seems these shocks will fit with 3" bumpstops?
Assume will need longer set of coils like Synergy, Metalcloak etc?

Would appreciate some pics and feedback
 
That's basically what I'm running. I have Fox external reservoirs for 4-6" lift even though I'm using 3" lift coils. The 3" bumpstops are enough to keep the shock from fully compressing on full stuff.
 

jesse3638

Active Member
Why not just run the appropriate length shocks for you coils? I'd be more concerned with coils unseating and falling out than over compressing my shocks.
 
Why not just run the appropriate length shocks for you coils? I'd be more concerned with coils unseating and falling out than over compressing my shocks.
Dual rate coils like Synergy and Metalcloak need pleenty droop before they unseat. So might as well run longest shock you can fit.
 

jesse3638

Active Member
Dual rate coils like Synergy and Metalcloak need pleenty droop before they unseat. So might as well run longest shock you can fit.
Yes I assumed you meant you were running standard 3" lift coils with a 4-6" lift shock. As mentioned just make sure you have enough bump.
 

desertrunner

Active Member
Why not just run the appropriate length shocks for you coils? I'd be more concerned with coils unseating and falling out than over compressing my shocks.
idk i did a franken lift on my 2 door and i just took the time to cycle and measure everything and i ended up with evo 2" plush with rancho shocks made for a 4" lift and it works just fine. As long as you measure out everything correct you can match the shock extended length to the spring droop and match the compressed length to the bump stop. worked for me with the evo / rancho combo but every shock and springs will have different results.
 
Why not just run the appropriate length shocks for you coils? I'd be more concerned with coils unseating and falling out than over compressing my shocks.
I would caution against using your shock to limit down travel. Over-extending a shock can damage it just the same as over-compression. In my experience, the control arm and track bar geometries limit the down travel before my springs want to unseat, so I got the longest shocks I could fit with the amount of bump stop I was using.

The appropriate length is determined by the compressed and extended length of the shock compared to what the rest of the suspension is capable of. If the compressed length is shorter than the bump stops allow and the extended length is longer than what the coils, control arms, and track bar allow, then your shock is safe.

EDIT: I was wrong about warning against using shocks to limit down travel. I left the rest of the comment so the thread still made sense.
 
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jesse3638

Active Member
I would caution against using your shock to limit down travel. Over-extending a shock can damage it just the same as over-compression. In my experience, the control arm and track bar geometries limit the down travel before my springs want to unseat, so I got the longest shocks I could fit with the amount of bump stop I was using.

The appropriate length is determined by the compressed and extended length of the shock compared to what the rest of the suspension is capable of. If the compressed length is shorter than the bump stops allow and the extended length is longer than what the coils, control arms, and track bar allow, then your shock is safe.
Ok.

Edit: I couldn't leave his response unanswered. I tried...haha.

Sounds intelligent enough but is hardly true. Down travel will and should be limited by one of two things, shocks or limiting straps. Using the track bar and control arms will cause far more droop than other components are capable of ie...drive lines, clevite bushings, causing binding which could lead to failure.

While I agree if I were bombing through the desert with my vehicle constantly unweighting and/or leaving the ground causing my wheels to extend to max down travel, "topping" out the shock sharply at high speeds (shock rebound speed not vehicle speed) can cause damage. This is why trophy trucks use high and low speed rebound damping and limiting straps.

My 2012 JKUR is hardly a trophy truck so I don't feel me utilizing my full down travel at crawl will cause significant damage to my King 2.5's when they fully extend and limit my axle droop. Again with shocks too long and sway bars disconnected I'd be more concerned with my coils unseating and/or falling out while flexed and full down travel is used.

I'm sure someone with much more experience could chime in and correct me if I'm wrong.
 
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Ok.

Edit: I couldn't leave his response unanswered. I tried...haha.

Sounds intelligent enough but is hardly true. Down travel will and should be limited by one of two things, shocks or limiting straps. Using the track bar and control arms will cause far more droop than other components are capable of ie...drive lines, clevite bushings, causing binding which could lead to failure.

While I agree if I were bombing through the desert with my vehicle constantly unweighting and/or leaving the ground causing my wheels to extend to max down travel, "topping" out the shock sharply at high speeds (shock rebound speed not vehicle speed) can cause damage. This is why trophy trucks use high and low speed rebound damping and limiting straps.

My 2012 JKUR is hardly a trophy truck so I don't feel me utilizing my full down travel at crawl will cause significant damage to my King 2.5's when they fully extend and limit my axle droop. Again with shocks too long and sway bars disconnected I'd be more concerned with my coils unseating and/or falling out while flexed and full down travel is used.

I'm sure someone with much more experience could chime in and correct me if I'm wrong.

I think I was wrong.

You might be right. I'm always weary of trying to use a shock as a structural component supporting any weight. At full stuff, the shock would be sharing the weight of the Jeep and can easily happen very harshly, leading to damage. For droop, however, the shock would "only" be supporting a portion of the weight of the axle, tires, etc. You bring up a good point that for most Jeeps, this happens slowly while crawling and not at speed. It's much less likely to be a violent event.

You made me curious, so I reached out to the technical support of a couple of manufacturers to see if they recommend using the shock to limit down travel.

In the effort to prevent spread of misinformation, I'll edit in a disclaimer in my original comment.
 
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