After installing a 2 1/2 lift kit on my jeep YJ I couldn't get the track bar to bolt back in. I shopped around a bunch and found a lot of solutions but most were expensive aftermarket replacement track bars. The others needed welding.
I devised this solution after seeing a youtube video on the installation of a Spohn adjustable trackbar on a lowered Tahoe. Additionally there were some blog posts that show lengthening the track bar by cutting it and welding in/on an insert or sleeve.
The Track bar was introduced in the YJ wrangler to make the pure leaf sprung jeep safer and reduce bump steer.
Step 1: Cut the Bar
To make the track bar longer I figured out the best place to cut it. Since the bar is bent in 2 places I chose a place in the bar where lengthening it would be effectively parallel to the axle. Then I found the mid point in that span and cut the bar in half using a right angle grinder and a cuttoff wheel (~$20 from Harbor freight).
Step 2: Measuring
Using a digital caliper I measured the outside and inside diameters.
Step 3: Tap or Die
Now I needed to decide how I was going to extend the bar. I intended to cut threads but needed to figure out whether I would cut them on the inside or the outside. So I referenced a tap an drill chart to see which diameter lined up best with a common thread diameter.
I saw that the 0.827 ID of the bar lined up very closely with the 0.8125 required for 7/8 14. I could have gone with 7/8 20 but chose the 14 threads per inch route for a very simple reason $$.
I was able to get a 2 foot bar of 7/8 14 threaded rod from Amazon for $20. I also got the tap I needed from Amazon for $14
Step 4: Tapping the Threads
I clamped the bar in my vice and started cutting the threads, I started with an adjustable wrench to turn the tap but switched over to a ratchet to make things easier. A little WD 40 makes the taping alot easier.
I wanted as much thread engagement as I could get so I ran the tap down as far as I could. This gave me about three inches of usable thread in each half of the bar.
Step 5: Cut the Threaded Rod
With the threads cut I could put the bar back together but with 2 feet of threaded rod in the middle it is a bit too long. So with 3 inches of thread in each half and the knowledge I only needed to add about an inch to the bar length.
I cut the threaded rod using the right angle grinder and cut off wheel again. I cut two seven inch sections of threaded rod because I extended both front and rear track bars at the same time.
Step 6: Installation
Now with the bar reassembled I could install it back in the jeep. Normally, and as the Spohn bar does, the threaded rod would have had both right hand and left hand threads but again this wasn't my case for $$ reasons.
My extended track bar is adjustable but you have to disconnect one end and rotate it to change the length. Due to asymmetry in the bar, this means the bar can only be adjusted in 1/14 inch increments.
Some Jam nuts and Loctite on the threaded rod preload the threads keeping things tight and strong.
All total this project cost me $34 cause I already owned the grinder and ratchet.