Track bar adventures with AndyG

AndyG

Because some other guys are perverts
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Jul 30, 2018
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My '03 TJR has the hefty Rough Country adjustable track bar ...it's a stout, simple unit , has a good curve for clearance, and may be one of the best items they sell.

Another cool feature is (with their mount) both ends are oriented vertical, so the frame end mounts like the axle end ..and both ends accept the stock bushing. This also means it pivots with the bushing sleeve on the bolt, not at 90°, meaning a simpler connection that puts less stress on the bushing and bolt.

The downside is the factory bushings are junk, and that's really bad with 33" tires. Really bad.

Being a believer that a track bar , or control arm for that matter , is no better than the bushings , at some point I "upgraded" (so I thought) each end to Energy Suspension polyurethane 2 piece bushings with a 12mm bolt at the axle end. To some extent, it was better than the stock replacements I had in there, but marginal at best...marginal meaning I was closer to death wobble than I knew.

I put all Moog components on the front end with a ZJ tie rod and all of a sudden had death wobble from a bump. I'm like , holy cow , upgraded my way to death wobble ...here we go.

At this point I needed professional help, so I reached out to @Mr Blaine and @Dave Kispaugh (Jeeps West) .

Blaine pointed me toward my upper control arms , and sure enough, one bushing was loose in the mount , and Dave recommended getting away from the 2 Piece bushings in that track bar, and installing Moog K-7252 bushings (this is the Moog replacement bushing for a 3/4 ton Dodge truck). You have to either sleeve the bushing or upsize the bolt, which needs to happen at the axle end any way if you run big tires. Both gave great advice.

So, the short of it is the harmonic I generated found the it's way to the weakest 2 components once I beefed up the front end ...and that was enough.

So what all is there to learn here?

2 piece Energy Suspension polyurethane bushings don't belong in a Rough Country track bar for one , because the o.d. fit is not tight enough nor is the track bar end wide enough to capture all the material . The 2 piece design alone has inherent downsides as well.

Secondly, you are dealing with a bushing that is mostly all polyurethane...harder or not , it is still more material to compress...10 percent of a 1/2" is more travel than 10 percent of 1/8 " for example.

If you hold a stock track bar bushing in your hand and the K-7252 , it is obvious from the weight there is a big difference . The K-7252 sleeve is huge, has half the rubber , which means it has to be dense, and the outer sleeve is very thick as well . It's for a 3/4 Ton ,7500lb truck, it's up for the task, big time.

Also on a big note, thanks to Blaine, I learned that a weakness can be revealed by strengthening other things ...the control arm bushing mount I knew was suspect had never given me a problem, because the system was soaking up the energy when it was more stock and had the 2 piece bushings...it simply never got all the stress. Energy may eventually dissipate, but it's going to go as far as the system can transfer the vibrational frequency til it finds the weak spot if it's a hard enough lick and nothing else gives.

A sure sign you have weak track bar bushings, prior to bump activated death wobble, is having to counter steer excessively on wavy roads ...counter steer meaning as if driving with a side wind you are fighting. If the axle is floating left and right , the tires turn the opposite way as it does because of the road friction , and you have to nudge the wheel a lot.

To wrap this up, the TJ owner who does all the work he can needs to understand his track bar and how to make it stronger, along with checking all the mount points for the suspension
occasionally.

Including your lower shock bolts , you have 34 bushings you ride on, plus your body mount bushings. These things really are suspended ...it's something to think about.
 
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What trackbar does @David Kishpaugh like to use with the Moog K-7252 bushing?
Word is he likes the older curved style Rough Country , that Moog part at both ends , and uses a 14 mm x 80 mm bolt and grinds it a little shorter . You don't want it hitting the axle at that end or the differential when you flex at the frame end .

He makes the axle end nut a flag nut by welding a tab to it . Very good idea, not a place you want to cross thread or under tighten one.

I sleeved mine to use 12mm hardware at each end , which is still an upsize from the 10mm stock at the axle, and stock at the frame ...plenty . Then I bought the bit and 14 mm hardware to go bigger if the sleeves fail .

His set up is well thought out.
 
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No , mine is the older style with the big rounder curve for the differential.

The track bar depicted can be upgraded at the axle end with the Moog -7252....and should be given the bar is stronger and hard wheeling will stress the bolt and bushing more. The 10mm bolts sometimes snap. There is huge force here at times, it's a lever.

The other difference on that one is the frame end is designed for the stock tapered mount , very nice..it would be cool to find out if that end can be replaced with a Moog ES 3096 L at that end, and if that part is up to par for that job...good question for Dave.

The older style has a sleeve connection down low at the axle , so you can adjust it when mounted , nice but you only really adjust it once , and a loose sleeve can cause unwanted flex easily ...the new design simplifies it.

That's a nice track bar for the price....the question is just how good is the tapered end joint ...that's a $35-40 joint with Moog , and knowing RC , it's not a Moog, it's a Mexican made or off shore knock off.
 
Thank you for the informative write up and explanations....
I edited a correction on my compression theory . Less is more if it's denser.10 percent of 1/8 is less than 10 percent of 1/2 for example ...and with track bars, it's typically doubled because you have 2 bushings.

In this case , it is a huge upgrade, the only thing is there is a limited selection in 14 mm bolt lengths typically.
 
I have the newer RC Track bar and would like to upgrade the bushing. Making sure is this the right part
MOOG Chassis Products K7252 TRACK BAR BUSHING https://www.amazon.com/dp/B000C57YMU/?tag=wranglerorg-20
Yes, and that's a really good price.

Just remember you're going to have to upgrade the bolt... The i.d. is 14 mm on that bushing... You're going to need a 9/16 drill bit, a 14 mm x 80 mm bolt... And you're going to want to run the bolt into the housing to see how much to shorten it , grind it shorter with the nut on it , then remove the nut to grease the threads, coat in grease and anti size and install it . The bushings have to be pressed in.

12mm Sleeves can be had, I was fortunate to have a friend make one.

You want to do away with the stock 10mm axle end bolt set up .

If this is all too much, at lease get a Moog stock TJ bushing and replace that one .. you will notice it driving better likely. The stock bushing will not last long.
 
Yes, and that's a really good price.

Just remember you're going to have to upgrade the bolt... The i.d. is 14 mm on that bushing... You're going to need a 9/16 drill bit, a 14 mm x 80 mm bolt... And you're going to want to run the bolt into the housing to see how much to shorten it , grind it shorter with the nut on it , then remove the nut to grease the threads, coat in grease and anti size and install it . The bushings have to be pressed in.

12mm Sleeves can be had, I was fortunate to have a friend make one.

You want to do away with the stock 10mm axle end bolt set up .

If this is all too much, at lease get a Moog stock TJ bushing and replace that one .. you will notice it driving better likely. The stock bushing will not last long.
10-4 thanks , would a 9/16 fine thread bolt work ? I have a few of those grade 8 with nylock nuts.
 
Just something to consider - is it the amount (total movement ) or speed of the movement (bushing deterioration) that can cause issues?

Really , it can be one or the other , or some of both. If it doesn't move much , but does too easily , it's going to let the axle move easier.

It's not all about hardness, but controlled movement....at every bushing. Hardness/flex needs to be relevant to the forces at play for that particular bushing.

Big tires make the heavier duty bushings a good consideration, big tires change all the dynamics.
 
10-4 thanks , would a 9/16 fine thread bolt work ? I have a few of those grade 8 with nylock nuts.
9/16 is a skosh bigger than 14mm.

Dry fit it at the parts store , you could slightly drill the bushing..the inner collar is super thick. Be sure to grease /antisieze it well on the bolt shaft.

The larger hardware a great move at either end , especially down at the axle ..10mm is too small , plus a bigger bolt means less rubber , so it has to be denser rubber. It's an awesome bushing.
 
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I don’t know the actual length or offset ,but I have that track bar on my Jeep with a 2”pro comp spring lift. There are no fitting or clearance issues
 
I don’t know the actual length or offset ,but I have that track bar on my Jeep with a 2”pro comp spring lift. There are no fitting or clearance issues

i have a unique situation. and need an offset bar with a joint in that orientation. most are cocked off at that axle joint or arched at odd angles over the diff cover. i need a 3" offset with the joint able to clock the offset forward.
length is not really important i can change that.
 
i have a unique situation. and need an offset bar with a joint in that orientation. most are cocked off at that axle joint or arched at odd angles over the diff cover. i need a 3" offset with the joint able to clock the offset forward.
length is not really important i can change that.
I believe it has the arch over the diff cover. I will go out and get some pics of the joints in few minutes
 
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@someguysjeep , don’t know if these will help or not.it does offset some.
27976887-5A99-44DA-A527-4501C86B6418.jpeg
7EC6DFEF-1F92-4BBB-B48D-C914341DBBFB.jpeg
75CCC7AF-FE17-4A41-B1BC-1D1900F07801.jpeg
9F8BF2FD-A340-4BE4-9BAA-5043F163EA84.jpeg
596A3922-F46F-4790-8B82-CFD35746A463.jpeg
 
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i have a unique situation. and need an offset bar with a joint in that orientation. most are cocked off at that axle joint or arched at odd angles over the diff cover. i need a 3" offset with the joint able to clock the offset forward.
length is not really important i can change that.
I think if you look at the older Rough Country track bar... The one that has the bodacious curve... You might find that it has the clearance you need.

Also that would be an easy type to move the mount forward or make a custom mount. It seems to me.

Good luck and keep us posted with what you got going on
 
ay, thank you very much that was way more than called for. i appreciate you taking the time.......

yah the 1 pic in that link looked like it was ran the offset out front (red line). but your pics clearly show it's canted up n out (more like green line).

i do appreciate your help. thanx again.

rc tb.PNG
 
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