Real-World Reliability of High Performance Shocks

Well dang, thats some good info. Wish Id known that before I bought Kings living up here in the frozen tundra haha

Living in Maine, I guess Im going to find out in a few years haha

 

Bit of a late reply here, but still relevant -- I appreciate this very detailed info on temp ranges for shock oils.

Today I put my Accutune-provided 4-corners FOX 2.5 PE / DSCs through their first real work-out, maybe 60-70 miles total, in 3 segments with ~30 mins rest between, on rough single-track forest roads, loaded w/ ~800 lbs of cargo, at 85-90ºF ambient temps. Average driving speed of 30-35 mph, mix of washboard & a good number of fairly heavy potholes.

Anyway -- when I got out the check the shock temp by hand, I could hold my hand on the shock for a count of 5 before I had to pull my hand away. I figure that's about 135-140ºF or so. The remote reservoir was warm to the touch but nowhere near hot. I'd guess if the shock body was 140ºF the oil inside might be peaking at 150-160ºF.

I was wondering "how hot, for how long?" -- i.e. like ATF fluid has a temperature chart with an inverse correlation between temp. & fluid lifespan. I'm guessing shock fluid might have a similar chart, but it sounds like ~150-160ºF is considered modest and nowhere near viscosity breakdown or other heat-related degradation of the shock oil.

If so, that's pretty f%*#ign encouraging, because truth be told I've never driven a truck at 50-55mph on single track forest road (peaking at 70 mph -- don't tell nobody) -- and that's as fast as I ever need to go on rough surfaces. If these shocks are built for 200ºF+ oil temps I'm never going to approach that performance limit unless I'm desert running at 120ºF ambient w/ 1200 lbs of cargo at 75 mph, which I don't plan on doing.

 

It would have been great to put a temp gun on those shocks to get accurate numbers. But what you've found with your example is great information that I don't think many will think about, unless you're racing. We've compared Fox and King oil in the past, but in a new article yet to be released, we compare Ride Shocks as well. Below is some copy and paste from that article that will go along with your findings.


Not all shock oil is created equal. The oil’s job is to provide lubrication for moving parts, but more importantly, to stay at a consistent thickness for the piston to flow through without obstruction or air bubbles known as cavitation. Shock Fade happens when the oil heats up, expands, thins, allows for cavitation, and creates a negative ride quality and performance.

Fox oil offers amazing lubrication across a wide range of temperatures, and is less likely to break down due to heat. High lubricity and resistance to breaking down are critical for a long lifespan. Viscosity index is a measure of how much the damping will fade due to heat. Fox’s viscosity index of 400 degrees is very high and provides exceptional performance. King’s viscosity index of 150 degrees is an average rating which means it is much more prone to shock fade.

Ride Shocks has pushed this even further, by using an oil that outperforms the industry leading shock oils with a viscosity index of 500 degrees. The advanced polymer technology has a nearly identical viscosity index and viscosity VS temperature profile, as the Fox JM92, however carries a much higher boiling point. This allows for greater resistance to cavitation. The higher boiling point also makes it much easier to tune. Factor in that Rides’ advanced formula shock oil has a lower volumetric expansion rate, which allows shock pressure to be more consistent throughout a wide range of temperatures, that leads to better shear properties and an overall better performing oil.

 

Matter of fact, I have a good thermal camera (TOPDON model TC005,) & will take it on my next off-road-ish trip & update this thread w/ info & photos etc, under similar operating conditions. (Cargo load, speed, ambient temperature, etc.)