Control arms
- Thread starter Tebbsjeep
- Start date
DaveB
Long Jeep Fan
- Location
- Holladay, Utah
All of our rigs have the flex end at the axle and the rubber/poly end at the frame. It gives you a lot less clunking.
- Location
- West Bountiful, UT
Is the clunking from when the rubber or poly bushings wear out?
- DAA
- DAA
Great topic as my wifes JK has picked up a clunking noise in the rear end and for the life of me I can't figure out where the noise is coming from. I have decided to just purchase some flex joint rebuild kits and tear them down. What typically goes out first? Flex or rubber?
The reason I ask is because I went to install my new joints on my Cherokee, and they don't fit the brackets that came on my long arm kit. It originally had heim joints, and I guess my new joints have a bigger body. However they do fit in the axle brackets.
RockChucker
Well-Known Member
- Location
- Highland
I always ran mine with rubber at the frame. Now I have Summit Machine Flex Joints on both ends. But I'm not too concerned about noise in my rig.
I can't give you a number. Use your judgement--if the threads are going to pull the hell out, that's not OK.
DaveB
Long Jeep Fan
- Location
- Holladay, Utah
From what I have seen on ours the clunking comes from the flex joint loosening up. They aren't worn out and can usually be fixed by tightening them up (if the joint allows tightening). The Rubicon Express lifts we had in the past had the rubber end at the frame. I have also had clunks when the poly end of the control arm gets worn out.
gatchmo5710
Active Member
Great question. This is standard test we do on our aircraft (im a heli mechanic) every inspection. The problem with most companys is their lack of tolerances or information about what is acceptable. Maybe teraflex gives a number.... but what you can do is go buy a grade 8 or better bolt with the same thread. Engage in the same amouint and compare wobble between the joint and the new bolt. If its close run it.
And i put all my soft joints at frame, hard at axle.
Last edited:
gatchmo5710
Active Member
This is from my manual with 5/16 fine thread bolt. Lossen jam nut, check movement at attach bolt hole.
If total movement exceeds 1/16 inch
(1.5875 mm) rod assembly must be
replaced with serviceable parts.
(f). Movement less than 3/64 inch
(1.190625 mm) is considered negligible.
(g). If movement is between 3/64 and 1/16
inch (1.5875 and 1.190625 mm),
inspect rod threads, step (6)., or rod
insert, step (7).
If total movement exceeds 1/16 inch
(1.5875 mm) rod assembly must be
replaced with serviceable parts.
(f). Movement less than 3/64 inch
(1.190625 mm) is considered negligible.
(g). If movement is between 3/64 and 1/16
inch (1.5875 and 1.190625 mm),
inspect rod threads, step (6)., or rod
insert, step (7).
On the teraflex joint the rubber will last WAY longer than the flex joint.
- Location
- West Bountiful, UT
That's interesting.
The flex joints on my LJ don't have any way of tightening them. But they have over 100,000 miles on them and haven't started making any noise yet I guess that's okay. A good thing, too, since they are on all 16 ends. They do have zerks and have been greased every time I change the motor oil at 4,000 miles.
The Clevite bushings in the factory arms were showing some wear when they came off at less than 20,000 miles though.
- DAA
The flex joints on my LJ don't have any way of tightening them. But they have over 100,000 miles on them and haven't started making any noise yet I guess that's okay. A good thing, too, since they are on all 16 ends. They do have zerks and have been greased every time I change the motor oil at 4,000 miles.
The Clevite bushings in the factory arms were showing some wear when they came off at less than 20,000 miles though.
- DAA
I'm a huge fan of good clevite bushings. I was happy when Teraflex adopted the use of them. They absorb impact and vibration really well and last a long time if setup properly (including not tightening until the suspension is at ride height)
You do have to be careful, there are lower quality clevite bushings out there that do not last very long, especially the ones with a 'D' window cut out of the rubber.
You do have to be careful, there are lower quality clevite bushings out there that do not last very long, especially the ones with a 'D' window cut out of the rubber.