Correct as usual.

[plh]

"But increased part count adding complexity really isn't the reason the new caddy is in a different league , is it? Could it be...... Design and QC/QA?"

That's my Quote from above. I guess you... agree.

Ok.. But for examples lets not use stats that "clip" the bar graph. As you can see when you drive past a ford dealer, 1 in five new auto broncos aren't failing to pull out of the lot, are they? .99 seems like a bit of a sucky number. Maybe use .9999 or .99999 to come up with a more realistic representation of parts actually being pushed out the door. Then we get 99.99% vs 99.96% and we ask if the .06% is statistically relevant enough to choose a 3 speed over a 10 speed?

Then lets look at the major moving components of a solid axle vs a independent. 2 cv's vs 4, at something representative like 99.99%.

We get 99.98 vs 99.96... .02% between them, but still both seem like ridiculously high rates of failure to me. I must be buying black market chinese parts.

so... hell... lets keep it unrealistic for ya, and use only 99% reliability for something as simple as a CV

And we end up with Pieces of "poop" assemblies either way at 98% and 96%

So, it makes sense for customers to choose Solid over Independent solely on this level of utter statistical irrelevance?

Yea. Its a non sequitur.

I missed documenting an important factor. The OE specs are generally 99% @ end of life. Depending on the OE it could be anywhere from 150K to 300K miles. So in USA average miles driven per year are 13.5K, so a lifetime for the vehicle is considered 11 to 22 years. There is a reason that certain OE vehicles have a better life maintenance track record than others.

A certain department of our government keeps great records of what vehicles remain on the road (registered) by model year. Being statistics are great a generalization, by the time a vehicle is 20 years old, there aren't a lot of them left on the road. Accidents are a huge contributor to this and other factors of course. Its in the 35% range still registered.

Oh and as far as IFS vs Solid axle. People in USA expect a comfy ride. Mall Crawlers are much more common than rock climbers.

Design, design tools, manufacturing tool improvements - of course a lot of things have changed since 1958 - that transmission was designed with a pencil and paper, not so much in 2023.

 

[nickw]

A diesel 4bt cummins has about 200 moving parts. An electric motor has about.... 1. The electric motor will last longer, but does the electric motor last 200 times as long? Does the motors duration have to do with the inherent design, where the forces always move in one direction and are balanced, whereas the Ice engine has all parts moving in reciprocal motions and develops NVH?

Part count affects...

I agree....but I don't love the electric motor analogy, there are 200 vs 1 moving parts to your point but 1 electric wire vs 2000 complex electric connections....not to count the software aspect. I only bring that up because that is always a big selling point for electric vehicles, many less moving parts.....but modes of failure are just moved to software and electrical connections, which I'd argue make it less reliable and/or less prone for long term upkeep.

Look at all those old pieces of heavy machinery, fully mechanical, that start up after sitting in a field for 20 years. I suppose if one were to built a Rivian with the skill and care the built the JWST or Space Shuttle with it would last forever....since theoretically nothing would wear out, but I think Software is ultimately going to be the demise of these new-fangled rigs, heck, just trying to keep a desk/laptop or a cell phone operational for 3+ years is a struggle these days.

With that said, I agree with the IFS comments - I'd take it over solid axle. I had a 2001 Tacoma, a buddy had a 1997(ish), we put 500,000 between those two with very very few problems....

 

[plh]

I agree....but I don't love the electric motor analogy, there are 200 vs 1 moving parts to your point but 1 electric wire vs 2000 complex electric connections....not to count the software aspect. I only bring that up because that is always a big selling point for electric vehicles, many less moving parts.....but modes of failure are just moved to software and electrical connections, which I'd argue make it less reliable and/or less prone for long term upkeep.

Look at all those old pieces of heavy machinery, fully mechanical, that start up after sitting in a field for 20 years. I suppose if one were to built a Rivian with the skill and care the built the JWST or Space Shuttle with it would last forever....since theoretically nothing would wear out, but I think Software is ultimately going to be the demise of these new-fangled rigs, heck, just trying to keep a desk/laptop or a cell phone operational for 3+ years is a struggle these days.

With that said, I agree with the IFS comments - I'd take it over solid axle. I had a 2001 Tacoma, a buddy had a 1997(ish), we put 500,000 between those two with very very few problems....

Yeah, software will really drive the life of the vehicle shorter in my opinion. I've heard OEs discussing basically getting away from key fobs and using only your phone to unlock and start the vehicle. No thanks.

 

[Grassland]

Why would we only be worried about the axle, when it's just one part of the product? Is driver comfort the only reason for the shift away from solid axles, or is there more to it?

The Grand Cherokee went from SFA on the WJ to IFS on the WK because it drastically decreased the assembly time, IIRC. I'm sure road manors were a small factor in the decision as well, but not the primary.

I am not opposed to IFS, especially when done right. However still prefer stout solid rear axle.