Front Suspension Modifications

I decided that I needed to do something to improve the suspension on the truck. Although the lockers allow you to accomplish most anything, you can accomplish it even easier if your suspension is a little more supple. On my D-90 I had used a hinge on one of the front radius arms. This greatly increased the front end flex on the D-90, which is fundamentally identical to the Gwagen's front setup. I also decided to have new springs made up to give me some additional clearance.

The first step was to remove the springs. Those front springs are LONG (21" free, 13" compressed) and I needed to really flex out the front end to get them out. This was also a good opportunity to find out what limits the front. The one thing limiting travel was the shocks. I removed those and replaced them with a set of Warn Black Diamond shocks built for another truck. The Bilstein had 9" of travel, and the new Warn shocks have 12" of travel. Since you actually are able to most all of the travel on the Warn shocks, the real world difference is substantial. The Warn shocks measure 29.48" extended, 17.22" compressed plus another 1.5" for the adapter. The stock shocks are about 25" extended and 15" compressed. You can see the difference in length between the Warn's and the Bilstein's, don't forget to add another 1.5" for the adapter.

The problem with going with a longer shock is that it will be too long for the stock position. In other words, the shock would bottom out well before you hit the bump stops. As it turns out, there was quite a bit of extra room. That also means that in stock form, you probably don't get close to using all of the shock stroke available. That is alright since the radius arms would bind before you could use all of the travel on even the stock shocks. I used a shock with an eye/eye configuration instead of the stock eye/stud setup. The stud tends to bind up and under extreme flex can bend big time. I ran an stud/stud configuration on the D-90 and bent the snot out of that shock. Lesson learned. I needed to use an adapter for the bottom to accept the eye. This added another 1.5" to the overall length of the shock.

Since the mounting bracket for the lower mount is lower than the spring plate, this worked out about perfect. I should have the ability to use almost every inch of the travel available. You can see that even resting on the bump stop I have about an inch left, which is what you want for those big hits.

I removed the brake lines and lowered the suspension as far as it would go. It couldn't go too far before it would bind, leaving plenty of travel in the shocks unused. I then pulled the bolt from the front of the radius arm and lowered it again. It went completely to the ground without the shocks attached, and darn close with them attached! This shot is with the shock attached, and you can really get an idea of how much travel it is going to have.

Here you can see how much the front of the radius arm displaces when not bolted.

The first stainless line is in and the others ordered. I have a little extra length, but I'm ok with that since who knows what the future will bring. It also allows me more room to maneuver if I take the calipers off (bearing/half shaft replacement) or want to change springs.

The hinged arm is done! When on the road, you leave it bolted in place so that it will have the strong original design.

Off-road you pull the rear bolt and it eliminates the binding created be the radius arm design. You can see how it worked on my D-90 at http://www.d-90.com/prod/hinge.html

The Final Test:
With the radius arm in place, I did a quick test to show how the hinged arm works. In this first picture the axle is hanging free. No shocks, and plenty of brake line left. The second bolt is in place making the radius arm perform in its stock manner.

In this second shot, the only thing I change was pulling the second bolt out of the arm, allowing it to act link a hinge. The difference in travel is remarkable, I actually had to lift the axle to get the jack out from under it because it pinned it to the floor.

Here is a close-up shot of the bend in the hinge.