H3 No work metal bump stop clunk (work in progress)

[amrg]

This is my second atempt at this. As everyone has noticed, once you change from OEM shocks to bilsteins (or even using worn out oem ones), the UCA drops all the way and the only thing that stops it is a metal stop under it.
Normally thats ok unless u drive on really bad roads, drop off kerbs or like my situation, do high speed desert drives. The clunking gets very repetitive and annoying and the faster I drive the more it clunks and its very loud (it keeps making me feel im breaking something although I know its not)

Solution? You can go with limit strapa, but I thought I'd instal a polytherane bump stop on the metal stop.



I drilled out the existing hole for this to fit, and added a thick metal washer behind it to act as a backing plate. Here is a link to this, its 11/16 inch thick...

http://www.energysuspensionparts.com/proddetail.asp?prod=9.9102


So far Ive driven this setup for 5k miles and wheeled it 4 times (approx 65 miles of high speed crap each time so 260 miles total) and it held up fine. I believe ideally a 1" thick one wld be great as it wld improve durability of it and it doesnt reduce travel much. The 11/16" thick one barely stops the metal contact as it compresses once the UCA rests on it so a 1" will prob get u 3/16" less travel maybe? My first trial was a 3/8" thick one but it didnt stop the contact and it broke off since its too thin.
Ive also noticed that it completely eleminated a metal bind and pop I used to get in my CVs whenever I hit a pot hole while turning, so I know its doing good to my CVS over time.

 

[ZWilson07]

Looks good man.

On a side note, I have read a lot about the bilsteins opening up more drop. Do you know how much drop they actually give by switching them? I assume it is just suspension range that for some reason GM didn't think we would want lol? It is a little suprising to me considering I have never had an ifs 4x4 vehicle that let you safely have more drop, usually it is already maxed out to the safe limit.

 

[amrg]

Looks good man.

On a side note, I have read a lot about the bilsteins opening up more drop. Do you know how much drop they actually give by switching them? I assume it is just suspension range that for some reason GM didn't think we would want lol? It is a little suprising to me considering I have never had an ifs 4x4 vehicle that let you safely have more drop, usually it is already maxed out to the safe limit.

Can't remember exact figures, but its enough for your control arm to hit on the metal stop, and possibly more if the metal stop didn't exist (Possibly an Inch over stock shocks). Stock setup uses the OEM shock itself as the limiting factor, there is an internal rubber bump stop built inside it which prevents the control arm from dropping all the way to land on the metal stop (when the shock is fully extended). Over time as the shock gets used, the internal rubber bump stop gets tired and allows more drop and you get metal contact in full drop situations. I had this when my OEM shocks were worn out. Also if your leveled, ur more likely to get full drop on smaller pot holes then in non-level cases, since ur UCA is already close to the metal stop.

I just swapped out those bushings with a larger ones, they are 1" thick, and at fully drop the control arm doesnt rest on the metal stop. There is probably 1/8 " between the arm and the metal stop. Went wheeling yesterday and got a chance to do a 50 mile high speed test on them, no loud bang whatsover. Plus as I said earlier, they stopped my C.V. joints from binding whenever I used to get full drop while turning (which is a great plus)

 

[ZWilson07]

Thanks for all the info man and going in depth so much.

Im curious as to why so many different posts across the forums want the bilsteins for the "added drop" but in essence it isn't the drop you necessarily want if it is going to be coming into contact with the metal stop.

I guess in theory switching to the bilsteins and adding rubber stops give you a little more room then stock shocks with internal "bump stop" but I am assuming its a very small difference especially if you consider that once stock shocks wear out, they let the control arm drop fully as well.

:huh: maybe im just overthinking it all.

 

[amrg]

The added drop the other members want helps them when wheeling, as they would want their tires planted on the ground as much as possible to get better traction. The H3 has 4" of travel at the shocks, so an extra 1/2 " is significant. Some people mod the OEM shocks by adding a 1/2 " nut as a spacer.
I simply want to use my performance shocks yet stop the metal clunk that happens as a result. Due to my type of wheeling, the metal on metal happens at a very high rate it becomes annoying and may distract me from noticing any other sounds that may happen from real parts breaking.

 

[amrg]

Here is a pic of the new setup. 1" thick energy suspension control arm stop. This is at full drop for the UCA:


There is probably 1/4" space left there. I think while driving that gap would be leas due to the force the UCA would have while dropping.

 

[RamRod]

How is it working out for you??


Sent from handheld smoke signal device

 

[amrg]

How is it working out for you??


Sent from handheld smoke signal device

The last ones I used are still in perfect condition, but I opted to get a thicker one for durability reasons (they can take more hits and still last for a v. Long time)

 

[Hunner]

If you added a half inch using shocks alone it should not hit that metal stop hard.
If it does you probably have your torsions turned up too high.

If you are more than occasionally tapping the stop you need to slow down!!
In my test jacked up with the wheels off the ground it did not touch but a violent drop from a jump could take out more slack.

I added the nut years ago before we found the Bilsteins.

To get all there is you have to extend the sway bar links are they will be at max angle.

At that point I used to use limit straps.

The next thing preventing further travel is the OEM tie rod ball ends.
To confirm this just take off these items one at a time and it will become evident.

I then submitted my ideas and measurements to have custom tie rods built with spherical rod ends. I used those for 40,000 miles on my 06 and now 60,000 on my 08 and they are still not loose. Debunks the criticism by people using crappy Heims at the time for other purposes. That allowed travel with out binding.

The next step I did was make some extended bump stops.

If that stop you added prevents hitting the metal does it not limit travel?

You can find extensive testing of all of this back in 06 on an older Hummer forum by some guy that is much older now low these many years. 8 or so in fact.

 

[amrg]

Ive read your thread before, and it inspired me to add a 1/2" nut to my oem shocks before I eventually added bilsteins.
Ive done this on one truck and noticed that after I did that I started getting the metal on metal contact. Ive changed my sway bar end links and UCA under warranty and still got the clunk.
I also got that on 3 different vehicles ( 2 of my own and a friends) after swapping to bilsteins. The tie rods/sway bars were not the limiting factor on any of my 3 vehicles, and I confirmed that by jacking up my trucks which is why I opted to get this bump stop solution.
I also noticed on one of my vehicles that usually whenever I get the metal on metal clunk, its followed by a loud pop couple of meters down the road on the side where I hit the pot hole. Did some research online and came to a conclusion that it may be one of the spheres inside the c.v. joint unseating and reseating itself. I ruled out my tie rod ball joints as the issue since there was no feedback in the steering wheel whenever this happened.
Anyway, since I added the bump stops (the 7/16" one) I got rid of the poping noise and the metal on metal sound.

As for losing travel, the stop sits at an angle, jacked up I have 1/4" left before the UCA rests on the metal stop(this is when using a 1" thick bump stop). I expect that to be even less while wheeling at a high speed (which btw is necessary as I need momentum to keep going forward on very heavy sand/ climbing dunes), which is a compromise if it will save me from possibly damaging other parts (ie. C.v. joints) and give me piece of mind not hearing that loud clunk every 5 seconds.