C10 Shock Relocation Kit (1963-72)

No Limit Engineering

1963-72 Rear Shock Relocation Kit

One of the great features of the mid year C-10 model trucks that spanned from 1963-1972 is the “trailing arm” rear suspension. Still in use today on many large model automobiles by many manufactures, as well as the go to choice for NASCAR’s, trailing arm suspension have proved to be a wonderful platform for both cars and trucks alike. Known for excellent stability when cornering while offering a smooth ride, the choice was clear during GM’s heyday to use the system. As time went on, and raw materials began to climb the fate of the trailing arm suspension met its’ demise as they proved to be “too expensive” to make and with the new ’73 model makeover, came the decision to convert back to the profitable “leaf spring” rear set up. Now, just like every engineered item in this world there is always room for improvements or refinements, as engineers like to say and the trailing arm suspension that was produced from General Motors was good, but not great.

To understand we have to stop and think about this for a second. What makes a trailing arm suspension work so well is simple geometry; a triangle formation of arms or “link bars” is used to gain stability, where the front of the main link bars mount at a front cross-member relatively close together to then spread out towards the rear at a wide angle directed at each of the tires on both sides. A rear link, or “pan-hard bar”, is used behind the axle to help control “lateral” or side to side movement while still offering a good range of “vertical” or up and down motion.

What complements this “triangle of links,” is where the weight support of the frame is held by a set of coil springs, where placement is key to a more sound or steadfast system of inertia control. With the spring’s placement being mounted just outside of the frame, to the lower arms it allows for a sturdy and secure base no matter what the coil springs weight rating is which gives the occupants a better ride and the driver more confidence while cornering, plus more traction as well.

These were all the great things that GM campaigned about the Chevy trucks throughout the 1960’s , as ’63-’72 Chevy trucks came equipped with trailing arm rear suspension, while the GMC brand had leaf springs. What the designers of those trucks never dreamed that 45 years later people would view these trucks as performance vehicles and not work horses. So why were they so bad, and what can the modern man to cure the plague of problems that exists on the trailing arm Chevy’s? In search of those answers, we looked into the way that No Limit engineering outfits their new long bed to short bed conversation frame kit that we featured our October issue titled “Some Assembly Required.” Let’s take a look on what changes and how it installs in the following photos.

C10 Shock Relocation
C10 Shock Relocation
C10 Shock Relocation
C10 Shock Relocation

By far the biggest mistake made by the engineers at General Motors during the early sixties was the shock placement on the trailing arm suspension. But who knew that these trucks were going to be pushed to the limits of performance driving. No Limit found the cure for the shock placement mishap that gives C-10 enough “body roll” to make someone sea-sick. By re-locating the shocks “outboard” rather than inboard of the frame, your C-10 will become more stable in the turns. Also by moving the shocks behind the axle, they complement the ride quality as well as they can now control the “wheel hop” that many trucks are prone to. After we got our hands on No Limits kit , we started to remove the old shocks and the lower mounts by removing the “U-Bolt” nuts where the old items dropped right out.

C10 Shock Relocation
C10 Shock Relocation

Installing the No Limit kit began on the Driver’s side of the rear axle first as shown here is a look at the lower axle pad/lower shock mount being set in place under the trailing arm, through the u-bolt and tightened down in place.

C10 Shock Relocation
C10 Shock Relocation
C10 Shock Relocation

As for the passenger side of the axle, the lower shock mount shares duty with the pan-hard bar bracket that we coined “the shark fin” for obvious reasons. The Shark Fin and the pan-hard mounting plate is slid in place through the u-bolt on top of the trailing arm before the arm and the lower shock bracket/axle pad are installed and snug down.

C10 Shock Relocation

Next the pan-hard base gets is fastening hardware installed to hold the “fixed” end of the bar to the axle.

C10 Shock Relocation
C10 Shock Relocation

The lower shock bracket gets a set of shock “studs” bolted to them to allow for the shock’s mounting eye to set into, as well as the upper shock mount that is bolted to the frame. If this set up looks familiar, you have a great memory, as this kit can be purchased for a stock frame application as well, which is why No Limit chose to recommended this system on their new “back half” long to short conversion.

C10 Shock Relocation

Here’s the heart and soul on the suspensions system, the upper “spring bracket.” I say “spring bracket” because as mentioned before everything has room for improvements. No Limit has engineered this bracket act as a multi purpose bracket that can accept a factory style coil spring, or a “sleeve style” air bag to be used for adjustable ride height.

C10 Shock Relocation
C10 Shock Relocation
C10 Shock Relocation

No Limit’s pan hard kit is a clean and simple way to gain the proper geometry allowing for a tighter more stable feeling while maintaining control under heavy cornering. The frame mount is bolted in place through the fame on the outside, and underside of the drivers frame rail where as the fixed end of the thick gauge mild steel tube is fixed to the bracket located on the axle plate.

C10 Shock Relocation
C10 Shock Relocation
C10 Shock Relocation

The adjustable end of the bar attaches to the frame bracket underneath the rail where it gives you a few choices on mounting points. We chose the center or “neutral” setting which is perfect for all around driving. Why is this bar so special compared to the factory you might ask, well the answer is in the frame mounts placement as a longer bar reduces side to side movement or body roll is well as creating more traction or “tire contact” with the pavement.

C10 Shock Relocation
C10 Shock Relocation
C10 Shock Relocation
C10 Shock Relocation

To round out the install the shocks can now be installed by sliding the eyes of the shock over the bottom bracket first, to then repeat with the supplied bolt and nut on the top. Here again is where this kit works so well over the stock set up as moving the shocks outboard reduces body roll, and placing them behind the axle enhances ride quality. Now some of you reading this maybe wondering why the shock is set at an angle, or why is it so long. The answer is a tradeoff as by having it laid at such an angle it helps tune the weight distribution allowing for a smooth ride while combating wheel hop. The length of the shock also allows from a wider range of compression/rebound characteristics making a mid level performance shock seem as a more expense adjustable shock.

C10 Shock Relocation

So here it is all finished and back on the wheels ready to roll.