Effect of ambient temperature on shocks

I've been documenting stuff on my truck, before and after, for everything that I do, and like to "compare notes" to see what the difference has been in different circumstances.

As the temperature outside warms up in Las Vegas, i've noticed my Icon C/Os have started feeling a little soft. It's not a bad "soft," but looking through my notes on when I installed them over winter, there's a huge difference between how they feel now in 80°+ degrees and back when it was in the 20°+ degree area. I have no weight on the rear, and can't really tell the difference between the stock bilstein and the 5100s, fwiw. More or less, just watching the C/Os.

Of course, while out wheeling when it was around 30°-ish, after cycling the shocks a few times, they feel about the same as they do in the morning when I leave for work, about 70° or so.

Just curious to see if anyone else with other shocks notices things like this. Most of my wheeling is done mid-summer in 110°+ and curious to see if these things turn to mush being digressive and everything.

Of course, everyone likes pictures, so here's some obligatory shots of my commute on the way from my house to Lake Mead (POND Mead, rather.) And yeah, this is still in Las Vegas. Some locals might recognize the route. I could drive on the roads to get there, but wth is the fun in that? Right?





Kenny

 

Amazing how temperatures effect things eh?

 

Always, but nothing i'm not used to.

My dragster requires constant adjusting/re-valving for certain tracks and temps. Not really an option in my truck. Well, not that frequently, anyways.

Just wondered how some of the other shocks react to temperature/climate changes.

 

it is....it really is

i deal with it everyday at work with process variations from ambient temp

 

very noticebable from 20 degrees to 85 degrees....from stiff to mushy

 

I can only go by seat-of-the-pants here, but here's what i've paid attention to:

1. Taking the same route to work for 4 years. Same roads, same speed, etc (since getting this truck, just over a year)

2. 30 outside and 110 outside are complete different (obviously) but at the same time, southern Nevada doesn't really have seasons

I understand that nitrogen follows the ideal gas laws to the 'T' so it's likely it's the springs in this case.

So, just as a quick example: I hit a speed bump/drain gutter at 15mph while it's cold outside (i.e. shocks are cold) feels like the shocks are pretty damn stiff and don't articulate much, translating into the frame and into the driver. Same scenario with it being warmer outside (around 80) the shocks soak the whole thing up and the truck itself, and driver, feel almost nothing.

Not a concern, but more of a question. Just, if i'm coming down off of a rock/ledge/into a gully in warmer temps with the shocks warmed-up. That kinda thing.

I know that's what armor and sliders are for.

 

When the ambient temperature is colder then naturally things should feel stiffer. Thermal contraction is the reason for this. You're going to have tighter clearances in the components of the shocks because of dissimilar metals of unequal thickness will expand and contract at slightly different rates. At least until you get it moving and friction takes over...causing them to heat up to their normal operating pressure. Then the ambient temperatures will have a much less of an impact.

Now as far as the springs go, the colder they are the more rigid or stiff they will be. After driving for a while they won't encounter the heat build up like shocks will because there isn't any metal on metal friction involved with the springs. So they will soften up a tiny bit but not nearly as much as the shocks will. So effectively, the ambient temperature becomes the operating temperature of the springs.

All this mumbo jumbo I just described is why I think things seem stiffer the colder it is outside and softer when it warms up.

 

This explains why my trucks been riding better lately...

 

Rather the bound than rebound, since these are digressively valved. There's bump stops and such to help prevent any damage when bring the front end down with all the weight on it, but it's more of how the shocks will react to going from fully/close to fully-extended to full compression.

Definitely not out to disprove anyone. If I could, I'd be all over that shit and making my own shocks. Like mentioned above, I hit the same gutters and speed bumps, and there's a very noticeable difference between when it's 30 outside and and 80 or higher. The nature of the digressively-valved shocks (Icons in this case), in which, at slower shaft speeds/cycles hold their "stiffness," was ultimately my question. That, versus the progressively valved shocks.

Not mumbo jumbo at all. Shock's shaft thickness versus body thickness is kind of a no-brainer. Expansion rates, cross curves of stability, etc all vary ever so slightly. Understandably, different shocks are made quite similar with the valving being about the only difference in most cases. It was more of the "combos" I was questioning. Kings, IVDs, Camburg/SAW, Evan Walkers, etc.

The coils would require a fairly ridiculous amount of heat applied to them before showing to be "soft." Though the coils are treated in a way that they maintain their life spans for as long as possible through almost all conditions, obviously, they won't. As for the newer coils, they wouldn't be, or I don't believe them to be, as susceptible to cycling wear in different heat ranges versus worn or near-worn coils.

That's good info to know. As it's warmed up outside, I've noticed the front end being much more "manageable" and comfortable if that makes any sense. On and off road. They seem to cycle alot cleaner and smoother, though, maintaining a rigid feel in a lot of situations. I'm still running my anti-sway bar, but figured I'd dump it this summer when my bumper and armor are on it. Not that any of those would help out, but I suspect my front end will be considerably lower than it is now.

Better? Mine sure has. I've been trialling the stock bilstein, OME N182, and bilstein 5100s on the rear and just can't catch a break. Regardless of what's installed, it's headache-inducing hitting some bumps and stuff with no weight on the rear.

 

when its -40C my truck sure rides different than when its like 27C

 

Of course! Want to wait until everything is installed before re-adjusting and re-aligning.

I can agree in that I don't really give a shit either. Just a general inquiry into whether or not all these $1k and up coil-overs all go through this or if anyone even notices. This IS my first truck (other than my '99 4x4 tacoma, r.i.p.) that I'm really putting any $$$ into and plan on plenty of carnage and destruction.

Coming from a world of cars with, generally, only an inch maximum travel (usually at launch.) Those things are stiffer than all hell, regardless of temperature, but lap times and ETs can show when a suspension system is out of "tune."

Not much I can do with these, or that i'd want to. It's more for exploring, camping in hard to reach areas, a lil' billy goat action with some other off-roaders from time to time and the like.

Kenny

 

I can def feel my set up turn into mush after a good hour in the dezert. Usually in the beginning of my trips I can get the whoops section at pretty good speeds and coast thru. I couple hours in and I start hitting the bump stops easy and I can feel my bypass and coil overs heat up.

 

ohh ambient temp my shocks are total titty bouncers, no matter if its 50* or 100*

 

pics?