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Posted

I have a 2019 rst and plan on getting bilstein 5100s adjustable height shocks and Icon Tubular UCAs. In the installation instructions for these and most other UCAs they have you cut off the droop stops. I’ve read a lot of concern of letting the lower arm droop too low while taking out the front strut assembly out with the potential to cause damage to the cv axle.

So my questions is wouldn’t cutting off the droop stop potentially cause problems with letting the arms droop too low? This is mainly a pavement princess with occasional dirt roads for hunting and what not, so I feel like the only time it would be at full droop would be when lifting the front end to rotate tires.

Posted

Just some more information this is icon’s response.

 

When using our coilovers we recommend to removing the droop stop to get the full travel out of the coilover and suspension. Without removing the droop stop you run into possibility of crashing in to that droop stop causing harsh ride conditions. We have not had any issues when testing with added stress on the cv shafts in the air. Our coilover and control arm are designed to stay within the usable travel of the suspension with out bind. being drooped in the air to changes tires will not hurt the cv axles 

Chuck Graves
Sales / Customer Service / Tech Support

Posted

Icon has been good to work with and they know their stuff. I haven't ordered any ICON stuff recently but ran a bunch of their gear on previous vehicles, off-roaders, and rock crawler type. I would imagine they are confident about what they say, otherwise it would open themselves up to a whole world of liability damages. These written responses are particularly tough to argue.

Personally, I would keep an eye on the ABS sensor wires, brake lines, CV boot (the rubber part) stretching/tearing and any other wires/sensors and call it a day. Those CV axle internals are pretty stout and I they hold up just fine for installs and tire rotations.

 

IANAL nor am I a mechanic, just a guy who's wrenched on his own cars/trucks for many years. This is my first GMC though so take it for what it's worth.

Posted
2 hours ago, Splitarrow said:

I have a 2019 rst and plan on getting bilstein 5100s adjustable height shocks and Icon Tubular UCAs. In the installation instructions for these and most other UCAs they have you cut off the droop stops. I’ve read a lot of concern of letting the lower arm droop too low while taking out the front strut assembly out with the potential to cause damage to the cv axle.

So my questions is wouldn’t cutting off the droop stop potentially cause problems with letting the arms droop too low? This is mainly a pavement princess with occasional dirt roads for hunting and what not, so I feel like the only time it would be at full droop would be when lifting the front end to rotate tires.

I am suspect under the intended use you describe you would not likely have an issue.

 

However it does prompt some thoughts: Why does GM use extended CV axles on the TB/AT4 which is only a 2" lift over the standard 1500 series truck? Why does the only factory authorized lift sold on the GM accessories web page include longer CV axles?  In both cases the droop stops remain in place restricting the movement, yet, GM still thinks it's important to extend the CV axles. Why is it often recommended to remove, or at least loosen, the CV axles from the wheel spindle to reduce the stress when replacing the strut assembly?

 

Aftermarket parts are often an improvement over factory parts and automotive engineers aren't all geniuses (I have 2 in my family). However, it does make one wonder why GM would go through the trouble of having 2 different length CV axles if lifting on the standard axle length didn't present some issues during testing and development.

 

Just some thoughts.

No expertise implied or expressed

 

Posted (edited)
8 hours ago, RWTJR said:

I am suspect under the intended use you describe you would not likely have an issue.

 

However it does prompt some thoughts: Why does GM use extended CV axles on the TB/AT4 which is only a 2" lift over the standard 1500 series truck? Why does the only factory authorized lift sold on the GM accessories web page include longer CV axles?  In both cases the droop stops remain in place restricting the movement, yet, GM still thinks it's important to extend the CV axles. Why is it often recommended to remove, or at least loosen, the CV axles from the wheel spindle to reduce the stress when replacing the strut assembly?

 

Aftermarket parts are often an improvement over factory parts and automotive engineers aren't all geniuses (I have 2 in my family). However, it does make one wonder why GM would go through the trouble of having 2 different length CV axles if lifting on the standard axle length didn't present some issues during testing and development.

 

Just some thoughts.

No expertise implied or expressed

 

the make the CVs longer because the differential isnt lowered, if you did lower it the problem is solved.......the angle is more  important.....at 2" its probably borderline of not needing anything but GM probably found it cheaper production wise to just have longer axles vs making new brackets to lower it a an inch or so.......you wouldnt think that would be the case,  but seems like it is as most bigger lift kits just use drop brackets.....longer CV in a bad angle is still a bad angle, at 2" not really a concern , at 4"-6" and up it is

 

 

GM probably gets the half shafts for same cost as the standard ones so doesnt cost anymore to build than standard truck.....however if they had to make frames different or brackets than that does add cost and time between 2 models....slower production also adds cost, so just an idea and idk if this is true

 

 

 

Edited by Dunn
Posted

I have the icon stage 4 with the tubular control arms, I didnt cut the stops off. When I put my truck on the lift, the suspension hangs and doesn't get that close to need to cut em off.

  • Thanks 1
Posted
5 hours ago, Flatblack83 said:

I have the icon stage 4 with the tubular control arms, I didnt cut the stops off. When I put my truck on the lift, the suspension hangs and doesn't get that close to need to cut em off.

There ya go. Measure twice, cuss less. 😉 

  • 9 months later...
Posted

Thanks for this information. I’m installing icon aluminum ucas, 6120s, and 5100 rr. I wanted to avoid removing the drop stops

  • 3 weeks later...
Posted

Food for thought on this subject. 

 

No need to remove them,  your sway bar won't let the front end fall that far anyway. Even with the extended coilovers you can put your finger in the gap from the icon uca to the stop.  Even hanging on a lift without the wheels when you unbolt the extended coilover the lower arm falls 3/8 of an inch. Still no where near the stops.

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