Air Suspension Technical Info?

[White Shadow]

I wanted to do some research on the air suspension system used by Rivian, but I can't find much info at all. What do we know about it so far?

Is it a closed system that uses nitrogen in an onboard pressure tank, similar to what Jeep uses?

Or is it an open system that uses ambient air without a pressure tank, similar to what Land Rover uses?

Does the system have an air dryer (desiccant) to help with moisture freeze during the winter?

Do we know who manufactures the air suspension components (air bags, compressor, valve block, etc...)?


I'm a big fan of air suspension systems and it would be nice to know a bit more about the system in the R1 vehicles. Not a lot of info is out there that I can find though...

Sponsored

 

[240vPlug]

The sticker I saw on mine says Monroe. Pretty sure it uses ambient air. It does use a separate compressor for the air suspension.

As far as the use of desiccant or any other technical details I would be curious to know myself.

 

[R1Tom]

Also would love to know about desiccant. Concerned it will need service at some point. Don't want line freeze up....

 

[Zoidz]

Tenneco/Monroe is the OEM.

"Tenneco supplies parts to a host of manufacturers including McLaren. In fact, from its inception, Rivian has used a central valve body block from Tenneco that shares much of its design with one used by McLaren. In fact, McLaren and Rivian take a very similar approach to thwart body roll while maintaining excellent handling and comfort. They do so by utilizing a cross-linked hydraulic system at each wheel.

That means that Rivian doesn’t need a traditional anti-roll bar. In turn, that provides more articulation and eliminates the need for that bulky and heavy hardware. Now, future Rivian models will use Tenneco’s CVSA2/Kinetic H2 semi-active suspension technology. Rivian will integrate the components directly into its skateboard chassis. It should provide improved continuously-controlled damping and roll control without compromising off-road capability or comfort."

Articles:

BuzzEVNews

PRNewsWire

CarScoops

 

[electruck]

Tenneco/Monroe provide the suspension hydraulics. MT has reported that Rivian also worked with Ohlins for some custom valving.

As for the air bits of the suspension, not much has been shared about that. There was some press that the air shocks are sourced from Dunlop Systems in the UK. So yes, pressurized from ambient air using compressor, compressed air reservoir, drier... all the usual stuff.

 

[pnwr1s]

 

[Forager]

Open system. The compressor has a desiccant air dryer, very similar to Land Rover. The compressor is made by AMK. The compressor for the air ride is separate from that of the auxiliary air compressor system. There is only one valve block.

 

[White Shadow]

Open system. The compressor has a desiccant air dryer, very similar to Land Rover. The compressor is made by AMK. The compressor for the air ride is separate from that of the auxiliary air compressor system. There is only one valve block.

What pressure does it operate at? Does it pull in make-up air in the event of a slow leak? Does the compressor have a temperature sensor that shuts it down at a predetermined temp? What temperature will it shut down?

 

[MidnightRivian]

What pressure does it operate at? Does it pull in make-up air in the event of a slow leak? Does the compressor have a temperature sensor that shuts it down at a predetermined temp? What temperature will it shut down?

https://leandesign.com/contact/
Munro & Associates
1140 Centre Road
Auburn Hills, MI, 48326
Phone: (248) 362 5110
Fax: (248) 362-5117

Michael Oakes
VP Commercial Business Development
[email protected]

 

[White Shadow]

https://leandesign.com/contact/
Munro & Associates
1140 Centre Road
Auburn Hills, MI, 48326
Phone: (248) 362 5110
Fax: (248) 362-5117

Michael Oakes
VP Commercial Business Development
[email protected]

That's great, but Forager seems to know something about the system. Knowledge is power.

 

[Zoidz]

What pressure does it operate at? Does it pull in make-up air in the event of a slow leak? Does the compressor have a temperature sensor that shuts it down at a predetermined temp? What temperature will it shut down?

What pressure does it operate at? Dunno....

Does it pull in make-up air in the event of a slow leak? Yes, based on reports from people who have had leaks. COmpressor runs more frequently.

Does the compressor have a temperature sensor that shuts it down at a predetermined temp? Yes, people have reported that they have seen an "compressor overheated" alert message when playing too much with ride height.

What temperature will it shut down? Unknown

 

[Killer95Stang]

What pressure does it operate at? Does it pull in make-up air in the event of a slow leak? Does the compressor have a temperature sensor that shuts it down at a predetermined temp? What temperature will it shut down?

I was told unofficially that the system operates at 7 bar during normal driving. A friend pulled up RIDE and saw that my system was operating at 1.5bar and he asked a Rivian tech that was a remote trouble shooter about my suspension issues. He said my system seemed to be operating at too low of pressure and that probably indicated a failing compressor. Next day, I had a complete failure of the system, but I didn't have a leak, because the R1S never sunk to its lowest position.

After the a related drive system failure, it was towed into the SC. Ultimately, a leak into the area surrounding the rear compressors and body control module (BCM) harness was flooded with standing water. That killed the compressor, tripped a 60amp fuse and corroded some plugs in the harness. After that was fixed and leak possibly fixed, everything is working fine. I guess I have a newer version of the compressor now.

If you have access to RIDE (not sure if that is still a thing), you can see what pressure your suspension system is seeing at normal operation.

 

[R1Tom]

Open system. The compressor has a desiccant air dryer, very similar to Land Rover. The compressor is made by AMK. The compressor for the air ride is separate from that of the auxiliary air compressor system. There is only one valve block.

I wonder how the desicant works in these types of systems. Does the desiccant need replacement at some point or does it run a resistance heater at some point and drive the moisture out?

 

[crashmtb]

That's great, but Forager seems to know something about the system. Knowledge is power.

Buy a report from Munro. Then you’ll have allllll the knowledge.

 

[Forager]

What pressure does it operate at? Does it pull in make-up air in the event of a slow leak? Does the compressor have a temperature sensor that shuts it down at a predetermined temp? What temperature will it shut down?

There was a salvaged compressor on eBay a few months ago. It had AMK parts numbers on it, it’s one of these models:

https://amk-group.com/en/products/air-suspension-compressors/passenger-cars/lfk/

Unfortunately I could not tell precisely which model based on the photos available and AMK has only very basic information available on their website. I’m an engineer and love tearing things apart, but I didn’t want to spend $300 on the salvage compressor to learn more.

I had a Land Rover LR3 that I personally maintained so I am very familiar with their design and function. My Land Rover had a Hitachi compressor (JLR later switched to AMK) and Dunlop air springs. The systems are very similar.

The compressors have a temperature sensor on the compressor head to shut off power if the compressor overheats. The internal seals are all plastic so heat destroys them. My LR3 compressor shut off around 190F.

The system pulls in fresh make up air to compensate for system leaks and vented off pressure when the ride height is lowered. The desiccant should be changed every 1-2 years depending on climate. In marine climates (like the PNW) the humid air saturates the desiccant quickly and when the temperature drops enough for a hard freeze the desiccant dryer will freeze up, restricting air flow. This makes the compressor work harder to move air into the system, leading to premature failure. We’ve already seen cases of air lines freezing up in the PNW with @jjswan33 ‘s R1T. I have not heard of a premature compressor failure, however.

Sponsored