Engineering Firm Munro & Associates Has Begun Tearing Apart A Rivian R1T; Here’s What They’ve Found So Far

Munro & Associates, the enginerds who tear apart cars to figure out how they’re built and how much they cost, have temporarily stepped away from their Ti-89s to place their hands on a Rivian R1T electric pickup truck. The team has begun its teardown, so let’s have a peek at what they’ve discovered so far.

I remember the first time I visited Munro & Associates; I was a 20 year-old intern in Chrysler Group, LLC’s (as it was then called) Advanced Concepts Engineering team, and my job was to study saddle-style gas tanks and different packaging setups for Power Transfer Units (Chrysler was considering an all-wheel drive variant of the RU platform that underpins the Pacifica). I recall attending classes that Munro was teaching FCA engineers, and I remember being reprimanded — a year after my internship, when I came on full time in a different group — when the Ford Explorer PTU that I’d checked out as an intern never made its way back to Munro. (I still have no clue what happened with that thing).

Anyway, after my two-year stint leading cooling system design for the JL Wrangler, I joined the circus over at the famous German lighting company, and started writing about cars. “Man, readers have no idea how much cool shit happens in the auto industry” was one of my first thoughts while working my new job. Among the cool things I wanted readers to see was benchmarking, specifically Munro’s benchmarking and costing analyses. In the summer of 2016, I’d run into Kevin, one of the many enginerds at Munro, while off-roading in the woods of northern Michigan, and we’d exchanged info so I could swing by Munro for a story. So in the fall of 2016, I stopped by to see what I’d remembered from my engineering days: thousands of parts just hanging on huge white pegboards, tables covered in suspension control arms and electronics and powertrain bits, detailed diagrams with dimensions and manufacturing processes spelled out — Munro was an engineer’s paradise, so I wasn’t surprised when my story on the company enraptured so many readers. Munro does cool stuff.

I don’t know why I’m writing any of this; possibly because Munro’s president, Cory Steuben, talks a bit about our history at the end of this Rivian R1T teardown intro video (thanks for the shoutout!), which I will now briefly summarize:

Right away, Cory and Sandy show off something cool: That front trim piece ahead of the frunk is actually held on by magnets!

This is bizarre, as almost every other company uses plastic clips to hold on plastic trim/closeout panels. In fact, just the other week I was talking about how Ford was using two-piece clips to affix the F-150 Lightning’s plastic trim that surrounds the frunk. I even mentioned my distaste for the fastener choice, since it was so easy to drop a clip into the dark abyss between the frunk and the inner fender/firewall (Sorry Ford, that clip is gone):

Sandy and Cory note that Rivian’s strategy here is novel, but a bit expensive — not just because magnets cost more than little plastic clips, but also because the magnets require ferrous provisions on the front end module. And not just on the main upper cross-car member, but also on the headlights; this, Cory notes, just adds complexity to the manufacturing process:

“I’d use 3M Dual Lock,” chirps Sandy. This is essentially a velcro-style setup, and I totally see why Munro & Associates’ boss would suggest that. So long as there are locating features in the trim piece to make sure it sits exactly where it should (and that’s one of the advantages of the magnet setup, I assume — the piece will want to center itself), that velcro-style tape should work well. And it’s cheap. I’m not entirely sure why some regular ol’ Christmas Tree fasteners and some holes wouldn’t do the job, here; maybe it’s an aesthetics thing since this is a class-A surface?

Cory mentions that the two little plastic boxes (which hold electronics for the light and the federally-mandated frunk release switch) hot-staked to the enormous injection-mold that makes up the frunk could be the same piece instead of two different shapes. This, he notes, could save Rivian some cash.

I’m glad Cory mentioned hot-staking, because I was looking for that term recently when trying to remove the fabric part of my a 1994 Jeep Grand Cherokee ZJ’s door trim. This bit:

Unfortunately, flipping the panel over revealed that the fabric bit won’t come off, as it’s been heat-staked. It’s actually quite an elegant way to join two pieces:

Heat-staking is basically like plastic welding in that it involves mating two pieces (with at least one of them being plastic) by heating up and pressurizing one of the plastic parts to create a joint that requires no additional parts, won’t rattle or squeak, and features a nice, clean look. This diagram from British manufacturing company Goudsmit shows how it works:

Here’s the process in video form:

Anyway, by using the same little plastic boxes heat-staked to the tub, Rivian may be able to save a few pennies, as reducing the number of unique parts reduces overall vehicle complexity and cost. It’s one of the many things that Munro frequently points out as a key cost-reduction measure, along with things like using the right materials in the right locations, using the right manufacturing processes to build certain parts, reducing steps needed to build a component or system (often by reducing the total number of parts used), reducing fastener count/using cheaper fasteners when possible, and so on.

Removing the frunk reveals some nice hardware: chillers and inverters and motor mounts and ABS pumps, and all sorts of coolant and refrigerant lines. Plus, you can see vents in the wheel liners to help facilitate airflow through the front heat exchangers (it reduces pressure aft of the heat exchangers, facilitating flow) — like Sandy points out, the way these parts are laid out just looks good. And yeah, the typical owner is never going to see these bits, but how something is presented under the skin can also play into “perceived quality,” so it all matters. Plus, as Cory points out, many of the coolant lines are short, and they’re made of nylon (lightweight compared to rubber) with quick disconnects, which are easier to assemble and, if I had to guess, less likely to spring leaks than constant-tension springs (which the Rivian has a few of, Cory points out).

Cory also points out that Rivian uses a traditional air-to-refrigerant condenser out front rather than a liquid-cooled condenser (which basically just uses a radiator out front to cool liquid coolant, which flows into a liquid-cooled condenser that looks like the chiller pointed out above). As Cory says, a liquid-cooled condenser would allow the entire refrigerant system to be tightly-packaged; Rivian’s approach requires long lines and hoses to the front of the vehicle. I’m curious to know why Rivian made this choice; I used to work directly with the head of Rivian’s thermal team (a sharp dude) so I have no doubt there was some good thought put into the design.

Cory and Sandy also talk about the R1T’s body, pointing out the structure attached to the outside of the frame rails, which is there to make sure that the very outer 25 percent of the vehicle’s front end is tied in with its main structure; this helps the truck pass the Insurance Institute for Highway Safety’s rigorous Small Overlap Rigid Barrier (SORB) crash test.

Cory also notes the main upper rail (the “shotgun”) — a part that’s normally tied in with a vehicle’s body and that’s normally hydroformed (see video above; it basically uses hydraulic working fluid to press metal into the desired shape) — is made of a different material than the aluminum body (it’s steel) and is not hydroformed (It almost looks stamped and welded? — see image after the one below).

I showed a shotgun rail in my Ford F-150 Lightning review as a way to demonstrate just how much body structure the Lightning shares in common with its gasoline counterpart. Have a look:

Check out that review to see more images of those F-150 Lightning rails; they’re nice and smooth — quite a contrast to the Rivian’s shotgun rails, which feature lots of welds:

Cory and Sandy also note that Rivian uses multiple brackets/jumpers to tie the outer fender to the shotgun rail. Sandy says he reckon’s there’s opportunity for parts reduction, here. Plus, you see those round indentations in the outer fender that tie it to the narrow bracket? Those are Tog-L-Loc Clinchings, three-step processes that clamp, draw, and lock two pieces of metal together without using fasteners or welds.

In the video, the engineering duo gets into into lots more detail, talking about how the Rivian uses unique fasteners (a big no-no, when it’s avoidable), Cory shows a headlight access lid that seems entirely unnecessary/costly, there’s also an overly-expensive cast aluminum bracket holding the front end module to the shotgun rail — it’s all great stuff, so watch the video and get nerdy.

I’m pumped to see more as the team at Munro & Associates continues to tear into Rivian’s impressive pickup.