Twin Tube Vs Mono Tube Shock Absorbers | Know Your Parts

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Video Courtesy of KYB | www.kyb.com
Transcript:
Hello there, I'm Mac and this is Aaron. We're going to show you the difference between a twin-tube and a mono-tube design shock absorber. To do that we're going to use the specially made clear demonstration units. This one is an example of a typical twin-tube unit, and this one is a mono-tube shock absorber. As you can see, both the twin-tube and mono-tube designs use hydraulic fluid and mount on the vehicle the same way.
Let's begin by looking inside the twin-tube. It uses two separated fluid areas, an inner working cylinder, and an outer fluid reservoir that acts as an expansion area. In a gas shock, all of the oxygen air is replaced with a low pressure nitrogen gas, about 50 to 100 pounds, to reduce foaming. The basic components are a shaft and piston that move up and down inside a working cylinder. There are hydraulic valves inside the traveling piston, and there's also a hydraulic base valve at the bottom of the working cylinder.
The fluid is pushed back and forth between the inner working cylinder and the outer fluid reservoir. As the shaft and piston passes up and down, you can see that fluid passes in and out of each cylinder. The calibrated resistance that each valve provides to fluid travel is what determines the amount of damping force that the unit will have. This basic function works well for most vehicles, especially when a vehicle is used in normal to moderate situations, and when passenger comfort is most important. However, during more demanding conditions, when the shaft and piston are moving more rapidly or traveling further, a churning effect and foaming starts to occur.
This condition decreases its effectiveness. In fact, performance in some cases can be reduced as much as 50%. This condition is similar to having air in a break fluid line, which causes a spongy brake pedal. The KYB twin-tube shocks and struts use high quality valves that improve fluid flow and create less churning. They also utilize and anti-foaming check valve at the top of the expansion area to reduce the amount of gas entering the fluid chamber and thus maintains a higher level of performance.
Now, let's compare the twin-tube design to the mono-tube. The purpose for the mono-tube design is to have a shock absorber that is more responsive, has additional body control, will not have any fluid aeration, and still has a comfortable ride. As you can see, the mono-tube has a single cylinder, a wider piston, and doesn't use an outer fluid reservoir. The entire diameter becomes the working cylinder, which increases the hydraulic valving area.
The mono-tube uses a high pressure nitrogen gas, typically 250 to 300 pounds. The gas pressure and the hydraulic fluid are separated by a floating piston so that the gas and fluid never mix. The gas areas becomes the expansion chamber, and the fluid portion has 100% fluid. Because the two never mix, it eliminates foaming, and the hydraulic valving becomes much more responsive.
During vehicle movement, not all of the movement can pass through the valving. This puts pressure against the floating piston and the nitrogen gas chamber. On lighter movements, it has a cushioning effect. But on more aggressive vehicle movements, the gas pressure increases quickly and offers additional resistance. This gives the mono-tube variable performance based on driving conditions. Higher performance, just when needed.
You can also see that no matter how aggressively Aaron pushes and pulls, there's never going to be any aeration. The mono-tube fluid holding valving guarantees that, so the vehicle will never have any performance fade conditions. That's the mono-tube. It provides a more responsive vehicle control, additional vehicle stability, and less body roll. Did you know that in some vehicles they come factory equipped with a mono-tube? The KYB gas adjust is the right replacement mono-tube for those vehicles, but since most vehicles come equipped with a twin-tube design, the gas adjust and the mono-max, which are both a mono-tube design, become a performance upgrade.

[@zzzzzzzzzzzzzzzz8635]

Aaron is staring into my soul!

[@toyotabrony]

I don’t know if I should be leading or frighting by his glare 😂😂😂

[@rsauder]

Aaron demonstrates some superb wrist-action, pumping those shafts like a champ ( "You cont break me!")!

[@robles100]

Wrist-action 😆 🤔

[@tommybronze3451]

Seriously Aron is one step away from pulling out M62 machine gun and going all arnie :) And thanks guys for vid.

[@faunaireland4194]

Aaron sure knows how to work a shock! Oh my, I may have developed the vapors. I ordered them for my pickup after that demonstration.

[@votebluenomatterwho2532]

Fauna, think about what else Aaron could work for you...

[@TheNothing40]

Thanks, now I understand. This video should have more views.

[@rowboat0317]

Agreed. This is the best explanation of mono- vs multi-tube I've come across so far.

[@brandonhilligas7648]

Aaron looks like one of those quiet neighbors that keeps to himself and creepely stares through the curtains at everybody.

[@greatmystery9729]

Great video, direct and to the point! Thanks!!

[@ghostwrench2292]

Excellent video! Clear and concise explanation of the two styles.

[@logangill9052]

Aaron you’re the MVP! Nice work to the both of you, thanks for the clear explanation

[@blakeallen4050]

Very good info.! This will help a very fast dirt racing Honda Prelude FAST41🏁 keep the tire to track percentage, meaning more speed leaving the turns. Thank you both for this presentation.! Very informative.!

[@TechTimeWithEric]

Cool, I was looking at both for my S10, now I know that I want the Monotube. Thanks

[@targbroffman9297]

Eric Brunhammer, Did you go with those monotubes on your S10? I have an '03 S10 also, and i got a pair of Gabriel monotubes for the rear, just wanted to know if you installed monos yet and how you like 'em, thanks

[@Fuzion180]

Great video, I think I want monotube now

[@jamesmccansh3168]

I've run Monomax shocks on both my Silverados. They quickly became my favorite shock. Unloaded they make the truck handle well, loaded up, they're extremely stable. Unbeatable for the price.

[@JJsAttic]

Very good explanation thank you

[@erikng1003]

Thanks u for explaining

[@zali7125]

Tq sir.. Good explanation👍

[@dexter8584]

Nice vid. Team Mono here for sure.

[@ChandraSQLVideos]

Good info..

[@mark00820]

Hello Mac nice demo tubes. My question is did that twin tube foam in real time with so few travel cycles? Is this representative of even KYB twin tubes? Are their monotubes that are smoother than others. Recovery time for five minute travels on a choppy road? Thanks.

[@garymaya1767]

amazing, was about to dump cash on rancho rs5000x but heck with that, monotube is the way to go. Especially where I live, there are a lot of bad roads.

[@myopicchiwawa]

Penn and Teller of the Strutosphere!

[@FizuhcuL]

after having both style shock absorbers i prefer the dual shocks for a daily driven sports car

[@adibz959]

Does changing to dual shock absorber cause the car to have more body roll?

[@FizuhcuL]

adib z i keep them on about 16/18 dampening and theres very little but if your looking for dedicated track coilovers get a mono setup but i love these for the street over HSDs

[@elijahrose7913]

Can I get a twin tube shock for my semi truck?

[@justinkroeker1464]

Aaron might be a serial killee

[@aristotelisvenieratos6109]

Or a KGB agent

[@MrMizi7]

Which one is better for daily use

[@mytubie]

Can i put monotube in rear and twin tube in the front?

[@mytubie]

Anybody please 😊

[@saultube44]

Hmmm, I'll go with Twin Tube, my rear and lower back demands it. Anyway, I think these shocks need a spring to go back into a high position. I think that if they could make both work together but reduce their strength by half, so they're not too stiff; I think they'd be complementary

[@mxnkeyig45]

Aaron can we arrange something per chance

[@votebluenomatterwho2532]

Thanks Aaron, I think some wives that don’t understand that need a more up close and personal demonstration.

[@leonardoperez1638]

Boomer comment

[@nursingzombie6479]

Its such a shame that Aaron had his tongue removed by that horrible cat accident.

[@saultube44]

Combining both, would make a better Twin Tube, separating the Nitrogen, but with the second valve separating the twin tubes gives more soft cushion, improving the primary valve and the nitrogen cushion capabilities; why is this still not a product? A Strut are Twin Tube, bit instead of Gas uses a Spring, which is very dangerous to change/replace; but this could be used to improve even more the Twin Tube, adding on stop and bottom, motorcycle size springs, increasing cushion for the 4th time, and on top and bottom of the springs, on a flat surface, a thick disc of Sorbothane, cushioning a 5th time

[@CowMeCow]

Wow, how much Nitrogen do I need to re-fill the mono-tube?

[@KookiDowg]

Aaron scares me but good video though lol

[@Alex-dn5hi]

Where'd you guys find this cyborg

[@BenDover-lx1gh]

Vladimir Putin's son working for kyb 😎

[@samyw4480]

twin should more suitable for daily and family use. Ppl wont race everyday especially you have your family. If not a racer twin should be good enough.

[@nobodynoone2500]

Just cheaper. A monotube will be safer.

[@williamgoring7605]

Yeah I just want to know what the hell that guy in the blue shirt is doing