Heavy Duty Front Shackle Kit for '67-87 ('91) GM Trucks with Aftermarket (Lift) Springs, Greasable

This shackle kit increases the bolt size from 7/16" to 1/2" and increases the side-plate thickness to 3/8" for improved durability.  The bolts are Grade 8 for maximum strength. 

We make the shackles 1/2" longer than stock to help keep your lift springs from hitting the frame plus gold zinc plate them for corrosion resistance.  This technically lifts the truck 1/4" but is truly intended to keep the spring from hitting the frame.

The greasable shackles use drilled and cross-drilled bolts and drilled inner sleeves to channel grease to the bushings. You'll get longer bushing life, a smoother ride, and virtually eliminated squeak with the greasable kit. We use ORD exclusive hard compound bushings for greater bushing life and recently upgraded to a 4130 chromoly steel sleeve for even more durability. 

The larger bolt is ~30% strength upgrade, drilling the hole to make the bolt greasable gives back only about 1% of that strength.  Our greasable systems are a win-win for strength and durability/longevity.

Below is stock vs our HD shackles:

Tech Notes:

• About 95% bolt on. Requires changing the bushings in the leaf spring end and installing a urethane bushing kit in the frame part of the shackle mount. Both are pretty simple, remove the old bushings, put in the new.
  

• The same spring length changes that mess up the swaybar geometry also create problems with the front shackles. A longer spring will come back farther on full compression and with a stock length shackle, will probably hit the frame. This provides a really harsh bottom out and cause a lot of extra stress on the frame and spring hangers. That’s why our shackles are longer than stock.
  Due to varying vehicle configurations, we cannot guarantee that the springs will not hit the frame when using our shackles.
  

• Why aren’t they longer yet? Extra length on a shackle gives you more caster (which isn’t too bad in moderation) and tips your front pinion down. The pinion angle can quickly get to the point that the yoke has to be clearance ground for the driveshaft to rotate. This can be a major problem and is the reason we keep the extra length to a minimum.
  

• In 1988 the factory introduced a longer front shackle on K5's, Suburbans and some 1-ton trucks. These shackles are the same length as our HD shackles, but still use a small 7/16" bolt in the frame and thinner shackle plates.

Here is what happens with stock shackles: