Shock mount tech

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Jul 9, 2004
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Montgomery Co. TEXAS
FJ40, 4" lift springs, flipped, FJ60 rear axle. Looking at possible mounting the shock to the top of the axle housing. This will increase shock angle and I think travel. Any reason it can't or shouldn't be done?

I can't just move them to the other side of the crossmember cuz of the gas tank.

Help is always appreciated!
possible shock mount.JPG
possible shock mount2.JPG
 

CruisinGA

 
 
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Mar 27, 2003
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If the shocks are too long (might be if they were mounted at the u-bolt plate before) and they bottom out before suspension is fully cycled, this would not be a good idea. Otherwise, no problem.
 

pghfj40

 
 
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Maybe you know this already, maybe not... increased angle will decrease overall damping effectiveness and also change how the shocks "come in" over different sizes and speeds of excursions. Also more body roll on transition (unless you only moved the bottom out/not top in).

Oh... never this stuff though if the only goal is suspension travel (dunno your use).

HTH. -Ed '70FJ40
 

Mace

rock scientist..
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3 leaf pack.. Not the smoothest riding springs in the world..
 
Joined
Jul 9, 2004
Messages
4,020
Location
Montgomery Co. TEXAS
It rides smooth. The springs are BDS with the two short leaves removed, there is nowhere near that much arch in the springs when there is weight on them.

The upper shock mounts will stay in the original location. These shocks were originally on my '66 axle with the lower mount on the perch. When I converted to a fine spline rear I mounted the shock on the skid plate. From where the shock mounted on the '66 axle to were it sits in the pics, it is compressed nearly the same distance, just angled out more.

The rigs not really a daily driver, although I enjoy driving into and around town. A little highway, mostly in town stuff tho. My main consideration is safety, but some extra flex on the back would okay too.

I'll get the 3rd put back together tonight and try and borrow a forklift or something to flex it and measure for shocks.
 

77TLCFJ40

 
 
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66fj40x2,

I see your issue is one I am also struggling with. I want to increase my tire size and add a little shackle lift (SUA). In an effort to center the rear tires in the fenders, I would like to flip the rear springs which should add ~3" of wheelbase. The shocks currently mount to the front of the rear crossmember extending behind the rear axle to the Ubolt spring plate. If the axle moves back ~3", the front-to-rear angle of the shock is increased. If you can't relocate the upper shock mount to the back of the crossmsmber, can you spin/swap the ubolt spring plates so the shock extends in front of the axle instead of behind? That scenario may result in just as bad a shock angle. What is the right thing to do in this case? Thanks
 
Joined
Jul 9, 2004
Messages
4,020
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Montgomery Co. TEXAS
77TLC - I looked at that, but it puts the shock at a really bad forward angle, which would really get bound up on compression. It also extends the shock about a 1/4" from where it had been before the flip.

Ed - Thanks for the link, that helped.

Looks like the only ill effect may be dampening, but should net some extra shock travel. Ummmmmmm. What the hell, I'll give it a shot.

:beer:
 

honk

 
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Nov 14, 2004
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I think that shocks should be left until last and then mounted in a way that they're as vertical as possible, damping the arc movement of the wheel/axle. To do that they need to be mounted in different from stock locations when the suspension is changed from stock.
 
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