Last week in part 1 we got started with this project by showing you what we cut off and what axle's we'll be using in this build. Dynatrac Pro Rock 60 in the front and Dynatrac Pro Rock 80 in the rear. Both axle's have 5.38 gearing and ARB air lockers in them and are nearly bullet proof. I love the way Dynatrac builds these axle's and the thought and planning that has gone into them to make them, in my opinion, the best choice for an after market axle.
This week we are going to get the front axle placed under the truck, and get the lower and top link locations set. So follow along as we get busy with this build.
Since we are using the RST Three link setup on this build we'll need to get the lower link mounts, the upper link mount, and the panhard bar link mount all mounted on the axle. We have done a number of these builds already and have the measurements set as to where they all go on this axle so we'll just pass that section.
Once those were on the axle we then turned our attention to the frame mounts. In some kits out there the lower and top link mounts are place on the cross member. We don't like to do it that way because if you need to change the transmission or t case you'll need to not only hold those items up but you'll need to support the front of the truck as well just to remove them.
So we make mounts that attach these lower and top links to the frame instead allowing you to be able to work on the drive train without having to support the rest of the vehicle.
In the picture above you can see that we put the top link on the passenger side instead of the drivers side in this build. It's explained later as to why we do this.
In the picture above you can see that we put holes in the mount plate to give it more area to weld in. Instead of just welding on the sides, we now have contact in the center as well.
One other step we take to make our products better is to add these weld in washers to give a larger area for the bolt to sit on in all of our suspension brackets. This way the chances of the hole becoming oblong over time is decreased substantially.
It is more work for us to do but if it makes your rig better in the end we are happy to do it.
These frame mounts in the upper pictures are not complete yet as we have to add the gussets to them similar to the gussets below that support the mount from above it to the frame. Triangles.... you gotta love them.
After that was completed we could move onto making the links and setting the axle.
We centered the axle where we wanted it pushing the wheel base out three inches to clear 40" tires. The stock fenders will give way to Glassworks fiber glass fenders, which by the way has sold all of their molds to Advanced Fiberglass Concepts, soon and those will give us the added clearance we'll need at the back side of the fenders. We will also cut and channel the body mount that is just under the front of the door for added clearance. We'll cover that later.
We'll also need to french a portion of the frame in the picture below for the top link to pass by as well as change the orientation of the exhaust manifold flange from horizontal on the bolt holes to vertical to clear the top link. We could use a smaller top link like others do but it sees so much pressure that we don't want to compromise the integrity of our builds by putting a smaller top link in there. We'll do the extra work to insure a better product for you and your rig.
We also put the top link on the passenger side on these 2nd gen Tacomas, FJ Cruisers, and 4Runners with the 4.0 V6's and 4.7 V8's in the 4Runners instead of the drivers side. There are just too many items trying to share the same space on the drivers side with the drive shaft over there to put the top link in that same space.
Putting the top link on the passenger side ends up with a cleaner build and works exactly the same.
Once all the links were bolted on and the measurements were correct it was time to check the caster.
With the Dynatrac Pro Rock 60, and most axle's of this type, we want 6 degrees of positive caster which means that if you were to look at the front wheel and draw an imaginary horizontal line right through the center of it, that is your caster line. Angle that line so that the top of it is leaning towards the rear of the vehicle and that is now positive caster.
The following picture better illustrates caster and the picture is linked to the full article.