Subframe extension to spring shackle using 2"x2" box tubing

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 1:22 pm

Hi Everyone,
I have fabricated a sub frame extension on my 2003 AWD Astro which has the 2 inch body lift from Overland.
I thought of getting the $350 shackle bar kit from overland and having the bar welded to subframe, but decided to make my own using a 70 inch long piece of 2"x2" steel box tubing that connects the rear hanger to the front subframe.
For a bolt on, no weld installation I am using various Uni strut heavy plates and channel fittings.

The 2"x2" box tube has 1/8" wall thickness and weighs about 2.5 lb per foot.

I will post photos.

AP

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 1:27 pm

Uni strut flat plates hang from OEM shackle bolts.
2x2 box bolts to uni strut plates with 1/2" hex bolts.

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 1:30 pm

Detail of rear uni strut plates at oem shackle bolts

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 1:31 pm

Whoops photo sideways.

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 1:34 pm

Uni strut U shaped 3 hole and corner braces bolted to subframe forward OEM oval bolt hole

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 1:36 pm

Subframe and its existing oem holes to attach 1/2 " bolt to uni strut

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 1:38 pm

More images forward bolt to secure 2x2 box

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 1:42 pm

More images fporward subframe oem holes

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 1:45 pm

Use geavy washer or uni strut 3 hole backing plate inside subframe this image is rear oem hole in subframe

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 1:48 pm

Rear oem hanger bolts are 9/16" diameter, just un do hex nuts and attach uni strut 5 hole plates, then Loc tite nuts and retorque.

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 1:50 pm

Frame extension

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 1:54 pm

Use steel spacers inside tube to keep wall from bending when torque bolts

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 4:15 pm

Once all parts are torqued and double checked, i plan to paint on "torque stripe" with blue lacquer on the hex nuts, etc.
Then if a fastener loosens after time due to vibration, the straight line of the stripe will be disturbed and it will give a visual clue to re torque fasteners.

AP

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 4:18 pm

Once frame extender is finished, i plan to bolt on Manik 4x4 brand nerf bars using the awesome Unistrut wing fitting which has welded gusset. See mock up image

Astrophysics · Post by **Astrophysics** » Sat Feb 28, 2015 4:20 pm

Chevy & GMC Vans

Chevy & GMC Vans

Subframe extension to spring shackle using 2"x2" box tubing

Subframe extension to spring shackle using 2"x2" box tubing

Re: Subframe extension to spring shackle using 2"x2" box tub

Re: Subframe extension to spring shackle using 2"x2" box tub

Re: Subframe extension to spring shackle using 2"x2" box tub

Re: Subframe extension to spring shackle using 2"x2" box tub

Re: Subframe extension to spring shackle using 2"x2" box tub

Re: Subframe extension to spring shackle using 2"x2" box tub

Re: Subframe extension to spring shackle using 2"x2" box tub

Re: Subframe extension to spring shackle using 2"x2" box tub

Re: Subframe extension to spring shackle using 2"x2" box tub

Re: Subframe extension to spring shackle using 2"x2" box tub

Re: Subframe extension to spring shackle using 2"x2" box tub

Re: Subframe extension to spring shackle using 2"x2" box tub

Re: Subframe extension to spring shackle using 2"x2" box tub

Re: Subframe extension to spring shackle using 2"x2" box tub