Technical Articles

Steering & Handling Problems -- Replacing the bushings in the Axle Track Bar W/ Energy Suspension Polyurethane.

by Paul.

As the remaining 78 & 79 Broncos still on the roads get older and older and rack up more and more miles, one of the most dangerous things that go wrong with our trucks is play in the steering that seems to get worse and worse over time. There are many components in the Bronco steering system that contribute to this problem, but one of the first things that should be replaced are the bushings in the Axle Track Arm. If you look at Figure 1 and 2 below, you can see that one of the bushings in my track bar was almost completely gone! My steering was so sloppy that even after replacing the power steering box, shaft, and flex coupler I STILL had to turn the wheel almost a 1/4 turn before the steering would respond. All of this play was caused by worn out bushings in the axle track bar.


Click on each thumb nail to enlarge

Track_Bar02.JPG (67250 bytes)

Track_Bar03.JPG (66773 bytes)

Track_Bar04.JPG (66582 bytes)

Fig 1. 

Play in bar

towards the rear

Fig 2.

Play in bar

towards the front

Fig 3

The way the bar

should look


Almost every single suspension company out there sells replacement axle track bars for the 78 & 79 Bronco. However, they are VERY expensive (SkyJacker's Adjustable arm cost well over $100.00 the last time I looked and even a factory replacement arm from TRW (P/N DS917) cost $60.00. However, if your Bronco is not lifted over 3" then you will not need an adjustable track bar. All you have to do is replace the bushings in your original bar.


Track_Bar05.JPG (22789 bytes)So, I called Performance Suspension Technology and priced Energy Suspension's replacement Hyperflex polyurethane bushings for my track bar (P/N 4.7108g) The price was right, just $10.95. So I bought a set and decided to give them a try. 


So, I'll explain how the installation went first and then go into detail about the bushings. To install your new bushings, follow these steps:


Step One -- The very first thing to do is to squirt some WD-40 on the two nuts holding the bar in place AT LEAST 24 hours before you remove the bar. I had a hell of a time getting this bar off until I sprayed WD-40 on the nuts and let it sit for a week. After that, the nuts came right off.

Step Two -- Make sure you have the following tools and parts:

A 1 1/8" deep-well socket and a 1 1/8" open-end wrench for the axle bolt & nut

A 13/16" deep-well socket and a 7/8" open-end wrench for the frame side bracket.

A new cotter pin

A heavy-duty torque wrench capable of AT LEAST 200 ft-lbs of torque.

Track_Bar06.JPG (61602 bytes)Step Three -- Jack up the right (passenger) side of the Bronco so you will have room to insert the 1 1/8" open-end wrench onto the axle bolt behind the track bar. Support the Bronco w/ a heavy-duty SUV or light truck jack stand under the control arm bracket. I also a put 2 1/2 ton floor jack under the frame for safety. You really don't want a truck this heavy to fall!!!

Step Four -- Remove the cotter pin from the axle nut and place the 1 1/8" deep-well socket and AT LEAST a 1/2" socket wrench on to the nut and place the 1 1/8" open-end wrench on the head of the bolt behind the bar. Remove the nut but do not remove the axle bolt yet. When the nut is off, lower the Bronco with the bolt still in place back to the ground.

Step Five -- Place the 7/8" open-end wrench on the front of the frame nut and place the 13/16" deep-well socket on the frame bolt behind the bar. I had to use two  8" long 1/2" extensions so that the socket wrench was behind the left front tire. I also placed three short 2x4 pieces of wood on top of the left-side control arm so I could rest the socket wrench on the wood while a broke the bolt loose with a cheater pipe I slipped over the socket wrench.

Step Six -- Once both nuts have been removed from the axle and frame side of the track bar, go ahead and slide the axle side bolt out and then the frame side bolt out and remove bar. It should slip right off. Be careful when you remove the bar. It's heavier than it looks!!!

Step Seven -- Since one of my bushings was almost completely gone, I only had to remove the bushing on the axle side of the bar. I used a 1/8" drill bit and drilled holes all the way around the old bushing until the rubber was loose enough to remove with a screw driver. I've heard of people "burning" out old bushings with a blow torch, but I was hesitant to use this method.

Step Eight -- Once both bushings are removed, smooth out the inside diameter (ID) of the bushing eyes with very fine 400 grit sand paper to remove any rust or minute scratches in the bushing eyes. If you accidentally scared the eyes with a screw driver or the drill bit (like I did), make sure you file down the scar with a round or half round file before you smooth out the eye with the sand paper. Also, make sure to clean the bushing eyes with a clean rag and some mineral spirits to remove any remaining grease or dust.

Step Nine -- Included with your new bushings is a pack of silicone grease. The instructions that came with the bushing were very poor but I believe you're supposed to smear the grease on the following components:


Grease the ID of the track bar bushing eyes.

Grease the OD of the bushings.

Grease the OD of the bushing sleeves.


In other words, grease all of the areas where the bushings will come in contact with metal. Do not grease the ID of the bushing sleeves!!! Once you have applied the grease, simply slip the bushings in each side of the eyes and insert the metal sleeve. My bushing went right in and I did not have to use a press.

Step Ten -- Install the axle side of the bar first. Do not tighten down the nut yet.

Step Eleven -- In order to install the frame side of the bar, I had to literally push the Bronco to the left (driver's side) to get the body to line up with the axle. I was able to do it by my self by griping the frame and "pulling" the body over until I could slip the frame side bolt into place. If you have someone to help you, just have them push on the passenger side of the Bronco or have them turn the steering wheel slightly to the right to line up the body with the axle.

Step Twelve -- Torque the axle side nut to 155-205 ft-lbs and the frame side nut to 119-161 ft-lbs. On the axle side nut, I torqued it to 170 ft-lbs first and checked to see if the cotter pin would line up with hole. I got lucky and it went right in the first time. However, if it didn't, I would have kept tightening the nut just a little more until the cotter pin would line up with the hole. Also, I had to jack up the Bronco again (just like in step three) so I could get the 1 1/8" open-end wrench on the head of the axle bolt so it would not turn when I torqued it down. Special Note: Make sure you check the shock tower that the frame side of the axle track bar attaches to for cracks and loose bolts. My axle track bar was putting so much stress on the shock tower with that bushing gone that it actually jarred the shock tower loose!!! I had to remove the shock absorber on that tower and remove the left wheel so I could have the access I needed to tighten the shock tower mounting bolts.


Okay! So, how does the bar with new bushings work??? Well.... great!!! I have absolutely no play in my steering at all. None. It doesn't even feel like a Bronco anymore! What a difference! This was the best $11.00 I've ever spent in my life. This Bronco has never, ever steered this well before, even when I bought it in 1988. I STRONGLY recommend replacing your old worn-out rubber bushings with these new polyurethane ones.


Well, as good as the steering is on my Bronco now, the truck still sways all over the road, but this because my tires are too small and the rest of the bushings in the front end are shot. But this is another project .............


Paul's Product Score: I give the Energy Suspension bushings a score of 8.9. Even though the bushings fit very well, were easy to install, and they meet or exceed what Energy Suspension claims they will do, I had to deduct points because the instructions were terrible. The instructions weren't even for the track bar bushings. They were "generalized" and had one short sentence stating that track bar bushings are similar to end link bushings and then gave a "cheesy" exploited view of a couple of poorly drawn end link setups. Maybe I'm just stupid, but I like well document instructions, especially when I'm doing something that I have never done before. Surely I can't be the only one who feels this way.