Fron upper A-arm. What support it ?

[lsv_palana]

Hello dear friends. As you know i want yo changed my dead rancho x9000 to kyb (modified) and now want to install bilstein shocks. Interesting question come to my mind.. what supports upper A-arm when it goes maximum down ? It seems it supported by shocks ? It cant be so.. there are no any bumpers.. no straps.. no anything... if my shock will be longer then original then upper a-arm will bumps on iron thing that holds down a-arm bumpstop... here is a photo: upper a-arm and no bumpers... do i need to worry about this when i install bilstein with external reserviour (it extend much longer then rancho or stock). What holds upper a-arm when it goes down ?

 

[amrg]

You have the following:

1. OEM setup (no lift and original shocks):
At full drop, the original shock has a small rubber stop inside it which stops the arm from going all the way down and hitting the metal. When the rubber is worn, it will hit slightly. (I had that before)

2. Rancho lift with Rancho shocks:

The rancho shocks have 2.5" travel. The original no lift shock has 4". So rancho travel is less than stock and prevents the arm from hitting the metal (also reduces front wheel travel)

3. Bilstein shocks:

They have more travel than original and rancho. For Some people the arm hits the metal all the time (like me) or part of the time. You can't stop this without installing limit straps that stop the arm before hiting the metal. I have 2 trucks like this (no limit straps) and so far no problem.

Note: at full drop the cv joint will bind slightly, after maybe 20 meters of the bind you will hear a pop from the cv. Apparently the bearings in the cv get unseated and then go back to place.... I changed C.V.s for both trucks at 150.000 kms (94K miles)

 

[lsv_palana]

Thank you for so good answer.. does anybody make bump stop gor upper arm on that metal thing ?

 

[amrg]

http://www.hummer4x4offroad.com/forum/showthread.php?t=7583


I tried this myself. It was very difficult to install because of space. With rancho it will be easier (4" more space under wheel well).
It will do the job but you will have to put a new one every 5000 Kms if you offroad. 10000 Kms no offroading. The polyrethane keeps breaking apart because the bushing is straight from the back while the metal stop is curved. It the metal was flat, I think it will last more but this means more work.

 

[alrock]

I've had the upper A-arm hitting the metal stop for years. You'll wear out the ball joints or bushings before you damage the A-arms.