Bagging a 3/4 ton GMC Utility Truck
 

Recently got this truck and was thinking about bagging it. Looking for recommendations on how to go about doing so. I was planning on using a parallel 4-link and possibly a watts link with bags behind the axle.

What are your thoughts?

Re: Bagging a 3/4 ton GMC Utility Truck
 

I love me a utility bed.

A 4 link would be fine. You might have some difficulty packaging the watts and behind the axle mounts but it can be done. Take some extra time with your layout since you wont be able to just raise the bed floor in the same way most do.

Re: Bagging a 3/4 ton GMC Utility Truck
 

Being a 68 3/4 ton, it's possibly a truck-arm rear suspension. If so, you could bag it just like you would a 1/2 ton. 4-bar set-ups are nice but not really needed if it already has T/A's.

Front stuff would utilize the same parts as a 1/2 ton as well except for the spindles (bags/plates/etc).

Re: Bagging a 3/4 ton GMC Utility Truck
 

It's a leaf spring truck

Re: Bagging a 3/4 ton GMC Utility Truck
 

I would do a pan hard bar instead of a watts link for ease of packaging. Plus how hard do you really intend to drive it anyways. A service body that lays down the shame at the auto cross?

But like any build decide on a few items first then the parts, and mods will follow easier.

How high do you want the truck? Stock height to a 4/6 drop. This way you can set up the bags at their natural height to make set up easier. Air bags are supposed to installed at there set height when installed for optimal performance. It your bag stands 8" tall sitting on a table. It should be that height when installed. I like to cut up to 1" of shims so I can dial in "spring lb/in" where a one, and done philosophy can not. I have used wood to find the height I wanted then had proper ones cut in aluminum.

Do you want to lay out to make loading easier? If so you want the weight resting on the axle/ frame not on the bag to prevent destroying it.

2 links while not ideal do the job quite well if you do not drive hard and fast on them. It makes the rear of the truck feel non responsive to tight turns. Never something you would notice cruising the highway or bouncing around town. I helped a kid my cousin knew due this to his C10 since he wanted it stupid low, and handling was not much of a concern. We moved his leaf spring mounts 14" forward, and up to match the desired ride height we aimed at. The bars have to be level to the frame at this height. Even if you have to use blocks to achieve this.

I drove it down a twisty road by my neighbor hood, and it was not that bad. If I gave it gas to rotate the rear end around, and the limitations came to light. Which is how I learned to drive. Throttle in slowly , and it was in its happy zone.

Re: Bagging a 3/4 ton GMC Utility Truck
 

Take a look under it and see if it has the trailing arm cross member with out the brackets on it. If it does and it should its an easy deal to convert it to trailing arms.
Jimmy

Re: Bagging a 3/4 ton GMC Utility Truck
 

I brought a 3/4 ton rolling trailing arm chassis for the utility bed truck. I reached out to CPP to see if their tubular control arms would work and if they made any drop spindles for 8 lugs and they stated that they dont.

So it looks like I'll be bagging the truck using factory control arms.

Re: Bagging a 3/4 ton GMC Utility Truck
 

73-87 or 88-98 drop spindles?

Re: Bagging a 3/4 ton GMC Utility Truck
 

“Flying Sparks Garage” on YouTube did a 69 or 70 3/4 ton 8 lug utility truck on bags recently. Might want to see what components they used (up front at least) and to get an idea of the results.