Shock topping out or limit of UCA downtravel?

Before I start... I know I know, I need aftermarket UCAs which are ordered. But, I am interested, more for knowledge than anything.

I have installed Bilstein 6112s on the 5/6 height with 600lb coils. the lift is just what I hoped and the ride is planted and good. I am concerned though that I get a big clunk when hitting things that cause the front wheels to drop like going over a speed bump (even slowly) or potholes/railroad crossings/etc... It is clear to me the down travel is limited, but it is not clear whether the shock is topping out or if there is something else limiting the travel like the stock UCA. I don't want to cause any damage, but I am also not too concerned since this is a configuration that Bilstein sells. I appreciate any thoughts. I have definitely found that working on and learning about my truck is a ton of fun. TIA!

 

More than likely your stock UCAs will or are making contact with the coils at droop. As far as damage- more than likely it’ll be cosmetic unoess you really send it and can bend the UCA if it’s a hard impact. An aftermarket UCA has a wider radius to clear the coils at droop.

 

I have the same issue. I think mine is shock topping out because I don't see marks on UCA or on spring body. Anyone know if shock topping out is bad?

 

What UCA would you recommend for 2.5-3 inches of lift? I was thinking of getting the OME ones.

 

It’s most likely the shock. Direct bolt in aftermarket shocks are typically designed for OEM travel. It’s when you get into extended or heavily modified shocks that you need UCA.

Hard to say without seeing it.

 

Any of the popular ones should suffice- SPC, icon, TC, camburg. I have no immediate experience with the OME arms but they look similar to a lot that are already out there so I’m sure they’re fine.

 

I don’t think it’s the coils hitting the UCA. I have 1” clearance at full drop. Do aftermarket UCAs allow help with this assuming it is the shock topping out? Don’t see how it would other than if geometry is corrected

 

The 6112 has a larger diameter coil similar to traditional 2.5 coil overs. I’m willing to be that the arms are binding on the coil. It should be quick to tell since the coating on the coils will have a chip or witness mark in line with the balljoint.

 

2.5” shocks with 3” coilovers fit with stock UCA.

OP just said he had an 1” of clearance at full droop…

UCAs only real benefit is to help with caster corrections on a lift due to the built in caster or adjustability. If you have extended shocks they will allow 5/8” more of droop but it’s pretty negligible in the grand scheme.

 

I could be wrong. I’m curious to see picture now.

 

1” of clearance seems like a lot to me.

 

I agree. I suspect he isn’t at “full droop”. Or it could be something else entirely, but without pictures it’s hard to say.

 

I’d the shock is truly bottoming out and not
hitting a bumpstop, they will be damaged pretty quickly.

 

Alright, at full droop (truck jacked up with tires off the ground) this is the clearance. About 1”.

 

I was more or less in the same boat recently with my ICONs and stock UCAs. When I had the truck on jacks I had a happy gap between the control arm and coils. The thing I dont see anyone considering is that putting the truck on jacks and driving over a pothole are to very different scenarios that the suspension reacts to. With potholes a sudden change in road elevation forces the tires and suspension to drop much more rapidly and the UCA should actually be dropping even further than what you see when the truck is on jacks, which means it is likely hitting the coilovers, albeit not bad enough to cause noticeable damage to them. I ended up swapping out my UCAs and it got rid of at least 75% of the noise in my case.

EDIT: Added an old photo of stock UCA clearance when it was on jacks

 

@aninzer , You can stick some painters tape on possible contact areas then go for a drive to replicate it. You should see where there’s contact after.

 

That’s really interesting! I’m crossing my fingers that new UCAs will be the key. I could definitely deal with 75% less noise. I’ll repost in several weeks after getting UCAs installed!

 

I’ll give it a try. Especially after hearing @ForceOfG experience.

 

@aninzer did the new UCAs fix the issue?

 

Jack it up. Report back.