Technical Next question - rear shock mount - crossmember?

Now that the front axles/spring are square...

The rear end was dropped by moving the cross member back and setting the axle (76 bronco 9 inch) in front of it. It's how it came.

That eliminates using the spring cross member as an upper mount for the shocks. The apparent solution is to mount the shocks on Pete and Jake brackets at the front of the axle and a new cross member above that. What material should I use for that cross member? I know that there 'should' be no load at the top, but I also trust Murphy's Law.

Or... if you have a better idea for rear shock mounts, I'm open to it.

 

pic courtesy of @badshifter. You should be able to make an upper shock mount off the front face of the crossmember with a lump of round bar, gusseted if necessary. Alternatively, but quite similar, a kind of floating mounting, with brackets to the top of the crossmember. No need for another crossmember methinks.

Chris

 

I mounted to the frame then dropped vertically down to the axle.

 

Piece of 2"x1/8" wall square tubing. Cut the bottom out to make it a channel. Outer end cut on one side and narrowed to the width of the shock then tapered back to 2". Original length of the top curled down over the outer end.

 

Will top of shock up in existing crossmember line up with the rear-end mount? Drill hole through cross member for bolt if it will.

 

While you're back there working on the rear suspension, you might want to kick the rear of the frame up to gain some axle/suspension clearance.

 

Here is a picture that may help. In your picture it appears that you might be able to locate the top of the shock inside the existing x member. You could also make several mounting holes to allow some ability to raise and lower the vehicle. On a truck I'm building, I made a 2 piece shock mount bracket that bolts together. It allows me to adjust for the shock length as well as tilting with multiple locations.


Here is a pic of the trucks rear with multiple mount locations . You don't need that many, but having more than one can be helpful.

 

I'd keep it simple and weld a tube ahead of the rear crossmember to mount shocks.

 

Interesting. Mine would need to come out at least 5 inches from the cross member (3 inches for the axle and 2 for the shock itself) and be threaded at the outer end, so I'm not sure if it'll work or how much stress it'll put on that connection. It would be very clean and clear the 3rd member with no issues. The built cross member will need to be stepped up at the center to clear. Thanks

 

n

Very nice. It solves any issue with clearing the differential. It would take some fabricating, but it's worth a try. Thanks

 

I am considering that. I'd need to have someone bend the tube to clear the differential. thanks

 

Thanks. I'm not sure that would work for me. I'm using the existing buggy spring, not coilovers. Coil overs would solve a lot, but that'll be in the next iteration of this car. The lower shock mount would need to go on top of the spring shackles and the shock at mid-length would need to be about 6 inches. I don't know if there's one strong enough at that size.

 

That may be an issue, but I'll work with 'what is' for now. When I'm ready to kick up the frame, I want it to go a lot further - like dropping the whole car about 6 more inches...

 

Can't you just come off of the side rails with a small bracket for the top of the shocks? I see no reason why you have to come off of the rear crossmember only.

Infact you could drill thru both sides of the rail and weld in a piece of tubing to slide a bolt thru the tube and the shock, or you could build a couple basic ears off of the inside the rails and mount the shocks thru the ears.

This would put both shocks in front of the axle but that shouldn't be a problem....


...

 

Whether you use coil overs or the buggy spring, you will still need the same kind of mount for the shocks in a similar location. The pictures were just to give you an idea of how things can be organized in relation to each other and still work properly. Many times we have a general idea of what and where, but when we start actually putting things in place, they sometimes interfere with one another. So, just a pic to see how someone did organize their parts.

 

Put a pair of Posies or similar lower mounts as close as possible to the inside of the ladder bar brackets, then bolt on the shocks holding them at mid-stroke and at around a 30 degree angle, and then fit a piece of tube angling up and back from the inside of the frame rail to the rear crossmember so that a bracket with a shock stud can be welded to it.

 

I personally like full crossmembers that go frame rail to rail. Square box tubing of 1.5"-2" with 1/8"-3/16" walls. I like having some adjustment for the shock angle so 3-4 holes side to side at each end gives multiple angle choices to adjust ride feel, and height.
With box tubing the bottom of the tubing can be opened up so holes will go through both sides and give a double shear mounting. Or you can build a multi hole plate welded to the bottom of the square tubing to bolt the top mount to.

 

If you come off the rear crossmember, your mount could be something as simple as a length of tapered angle iron with the appropriate size bolt (head cut off) welded in the V. Weld it to the crossmember with the open side of the V pointed down, that will spread out any bending loads on the crossmember.
If you make a separate shock crossmember, remember that the offset to clear the differential can be in the horizontal plain as well as the vertical plain.