How Many Fewer Moving Parts Does a Model S Have Compared to an ICE?

How Many Fewer Moving Parts Does a Model S Have Compared to an ICE?

I have been throwing out spitball numbers at friends that I think the Model S has 75% fewer moving parts than a comparable ICE? Has Tesla ever shed light on this? Would any of the brilliant engineers on this forum like to hazard a guess? Am I even close, or a hopeless fanboy? I'm not sure what parts I am referring to, I guess parts associated with locomotion, not things like door handles and sunroofs.

Cattledog | 15 March 2013

Thanks DouglasR. For those who didn't follow the link, looks like there are over 10,000 moving parts in an ICE. Now we need Tesla to weigh in.

mreichenberger | 27 June 2013

For me this is the Most exciting aspect of the tesla palatform and i think elon and all early Investors focused on that. Think of a BMW Platform Strategy. You have Diesel, Gasolin whitch is different Quality all over the World. You have different Emission Standards. Only to fit in LHD and RHD probably cost them more than the compleet Body Development of a New tesla Model. To fit in 10.000 Parts from different suppliers is a expansive Journey and is the Reason for Long Development cycles. When i First Saw the tesla Platform in the Show room, i Could Not sleep for 3 days behause tesla is a Revolution in Automotive like the introduction of the Internet in the IT.
A Platform Strategy with the tesla Concept, Costs you at least 90% less than with compustion Engines. Tesla wins the Race. Markus from munich

Nexxus | 27 June 2013

Just think about it. Just because the Model S isn't an ICE it has even less moving parts that are automatically a part of an ICE vehicle:

Entire exhaust system
Spark plug wires
Air breather/filter for ICE
All the hoses, canisters, filters, etc...for the emissions control systems required for an ICE vehicle

Just to name a few...

So overall the Model S probably has maybe 12,000 fewer parts to begin with.

randyy | 27 June 2013

I seem to recall being told there are 17 moving parts in the Model S. This was at a gallery so validity is questionable, but possible.

langzaiguy | 27 June 2013

No valves, transmission, belts, crankshaft, cams, pistons. I would guess far fewer bearings, too. Most of all, way less heat & friction! | 27 June 2013

The number of parts depends on what you are including. For the drivetrain, perhaps the 17 number is right.

If you're talking about the entire car, there are far more moving parts (like any car). Moving parts includes simple things like door hinges, visors and cup-holder sliders. More complex sections include power steering, window lifts, HVAC valves, flaps and compressor, fans, air-compressor, fluid pumps, brakes and suspension components. You might even include seat-belts and every switch too, since they are all moving parts.

shop | 27 June 2013

The Tesla door handles alone each have 8 micro switches, or was that 8 for the car?

jonesxander | 27 June 2013

@TeslaTap, I think we all know we're talking about just the engine elements.

cfOH | 27 June 2013

It's a car...ALL the parts move. ;-D

Mark K | 27 June 2013

The comparison can best be calculated like this:

1. Look at moving parts in an ICE engine, transmission, and exhaust.

2. Replace those with the electric motor rotor, bearings, reduction gear.

3. All other systems have roughly the same number of parts (like doors, windows, steering, AC, brakes, drive shafts, shocks, etc.) so leave those out of the equation.

ICE engine and transmission easily total in the hundreds of moving parts (and many static parts.)

So the delta number is roughly in the low hundreds.

But that understates it because the EV architecture eliminates many static parts too, which still can fail in an ICE car.

The model s battery pack alone has 8,000 cells, (a high number) but these have a measure of redundancy so they are not single points of failure which can stop the car. But many single static parts in the engine, transmission, and exhaust systems can stop the car from working.

From an engineering perspective, Electric drive is a far more robust and elegant solution. | 27 June 2013

@jonesxander "I think we all know we're talking about just the engine elements."

I'm so not sure. Is it the entire car, just the engine, engine and transmission or the entire drivetrain (and does it include the suspension components)? The comment about 10,000 moving parts in an ICE car sounds more like the entire car.

If just the electric motor, I'm not sure if it has ball bearings or not, but if so, do you count each ball within the bearing or is the bearing considered one moving part?

Sounds silly, but it's really hard to pin down a good comparison, although now I'm curious as to an answer!

SamO | 27 June 2013

I've seen the number quoted as "one thousand fewer moving parts" but can't find the link.

How many fewer fluids?

How many fewer sensors to check on the belts, fans and levels?

How many fewer interior buttons and knobs?

How many fewer mandatory smog/exhaust test-only trips?

Jamon | 27 June 2013

On my very first visit to the showroom, I remember hearing that ICE cars typically have 500-1000 moving parts in the drivetrain, while the model S has maybe a couple dozen. FWIW | 28 June 2013

Here's a thumbnail analysis of just the motor, and we'll ignore the bearings in both cases (which may have many ball bearings), and cooling (both have water cooling systems).

TESLA Motor - 1 moving part

A modern Fuel injected V8 (similar power to the Tesla):
Each cylinder:
Piston, connecting rod, 4 valves, 4 valve springs, 4 cams, 1 fuel injector (total 15 parts per cylinder)
8 cylinders * 15 = 120

Additional parts:
Crankshaft, 2 camshafts, timing belt (if a chain - many more parts), starter motor, starter relay, belt (could have 2), oil pump, fuel pressure regulator, gas sender gauge, EGR valve, air injection check valve, purge valve.
Additional parts: 12

Total ICE moving parts: 132

I'm likely missing a few, and you can easily argue for more or less parts with different engine designs, numbers of cylinders, valves, emissions control, variable valve timing adjuster, turbo charging, etc.

jonesxander | 28 June 2013

@Tesla.Tap, right maybe I was a bit hasty in my previous comment. I'll say it includes the engine, the brakes, and drivetrain.

I would also include the door handles though, because those could, and have, had some problems in the past.

djp | 28 June 2013

1416 less than a Chrysler 300SRT

wheatcraft | 28 June 2013

I was also told the Model S has a thousand fewer moving parts than an equivalent ICE car. I think I was told that by a Product Specialist at the Menlo Park store. So I don't have a solid "reference" for the number.

EcLectric | 5 July 2013

I was at the Menlo Park service center today, marveling at the simplicity of the 'bodyless' Model S they have on display there. I use all the parts that broke on my Subaru as a benchmark. Oil filler tube that broke, causing the engine to seize with only 60k miles? Model S doesn't have one. Oxygen sensor that died, costing a couple hundred bucks to replace? Model S doesn't have one of those either. Steering system that got 'metal flakes' in the hydraulic fluid and had to be replaced? I found that in the model S. In the model S, the steering wheel rod goes into a small housing in the side of the steering linkage. There is a single wire going from that housing to the electric 'steering assist' motor. No hydraulics to spring a leak, no squealing noise when you turn the wheel all the way. Simple.

Oil pump? Nope.
Clutch? Nope.
Air conditioning belt? Nope.
Throttle body air sensor? Nope.
Fuel injectors? Nope.
PCV valve? Nope.
Head gasket? Nope.
Valve adjustment? Er....... Nope.
Catalytic converter? Nope.

I will definitely not miss the falsely sad voice of the service advisor after my 'free inspection' (or 'check engine' light) telling me that the water pump is shot, and while we're in there that far, we might as well replace the timing belt, which, if it were to break, would destroy the motor, because unfortunately, it's the 'interference type' as are all high performance motors... So sad for you.... That'll be two-thousand dollars, please. But don't worry, when you get it back, it will run just as well as it does now. And we'll fluff your engine pillows while we have it, and give it a nice wash. Just sit down over here.... We are very sorry for your loss...

cfOH | 6 July 2013

EcLectric: Ha! Nice. What kind of Subaru did/do you have? Your post is a big part of why I'm selling my STI for the MS I have on the way. My daily commute is 4.5 miles on city streets. The oil temp never gets hot enough to burn off condensates and it's gunking up my engine. I'm facing a ring job with less than 53k miles! EVs simply won't care how far I drive.

EcLectric | 7 July 2013

I had a 2005 STi. I had only 62k miles on it when it seized. They wouldn't warrant the repair if I didn't let them put the same faulty oil pickup tube back in. Talk about planned obsolescence! "We won't warrant the repair for one year unless you agree to put in a tube that will fail in five."

The money I got for selling it barely paid for that repair.

The Subaru had a lot of useless, inefficient power. I am so happy I switched to Model S!

cfOH | 7 July 2013

@EcLectric Aha! I am currently driving my 2005 STi...good to see another person making the conversion. What drove (ha!) me to decide to abandon the STi was basically the fact that ICEs don't handle my commute well. I go <5 miles each way and the oil temp never gets hot enough to burn off contaminants. I'm basically destroying the engine every time I go to work, and it takes a lot of fun out of driving because I LOVE (almost literally) my cars.

The MS and the STi are two VERY different cars. Losing AWD is my biggest fear...I've come to depend on it to get me through the increasingly rare snow storm. I've also done a lot to the suspension and it now has IMO the perfect amount of understeer (just a hint under normal driving, but I can still kick the back out when I need to). Are you someplace where winter weather is a concern?

EcLectric | 8 July 2013

I'm in the San Francisco Bay Area, so I don't have to worry about snow. I did have a blast auto crossing the STi in the rain, though. That, and the sheer power it had on the freeway. It wanted to go faster.

All the breakdowns and the lack of usable power at low speeds far outweighed the advantages of 4-wheel drive for me. The STi annoyed me at every turn, while the Model S does the opposite. The STi key fob was too sensitive, so if I tried to tie my shoes while the key was in my jeans pocket - the alarm would go off. When the AC was working (had to replace the belt once, had a coolant leak - 2 trips to the shop for that one), you couldn't tell if it was on or off because the indicator was a tiny orange LED that was not very bright and was sitting about hip height, so you had to put your hand over it to shade it and bend down between the seats to see it. I like to drive with the lights on, but the STi assumed that meant you wanted the interior instrument lights dimmed, so I couldn't see the radio or clock during the day.

Now I get annoyed at... Having to drive and occasionally fill up my wife's ICE car. With the Model S, all you have to do when you get in is put your foot on the break, click the gear stock down once (into Drive), and step on the accelerator. That's it! It has more power than the STi on the freeway, and the same power when you are completely stopped. The first time I drove it, it was in the pouring rain. It handled great, even when I pushed it to see what it would do. The traction control kept it completely under control, and it still went fast!

Brian H | 8 July 2013

Don't break your foot, it's very painful and makes walking hard. Use the brake instead.

David59 | 8 July 2013

I have heard the number 14 used on more than one occasion. I also heard that the motor counted as one of the moving parts.

EcLectric | 8 July 2013

Sorry, I should have said "brakedowns".

Brian H | 8 July 2013

"put your foot on the break,"

No downs mentioned.

elguapo | 8 July 2013

I think it is too low, but the Tesla store in DC says the car has 19 moving parts. The salesman (or whatever they're called) had a list. It was mainly fans and pumps, but I don't remember everything. Even so, that seems very low.

cfOH | 8 July 2013

To count "moving parts," one must first define what "moving" means and what constitutes "a part."

Is a wheel bearing a part? If they're tapered roller bearings, is each roller a part, along with the inner and outer races, seals, etc.? You could easily have 20+ "moving parts" just in a single bearing.

So, until we know what they mean by those words, arguing about it is silly.

EcLectric | 9 July 2013

Paragraph 2, word 3

Brian H | 9 July 2013

Paragraph 3, word 35.