Twist Beam rear suspension swap from dead to live (add a diff, axles, hubs etc. to be like a SX4)

I am very curious after reading about DeDion axles made popular in Locost builds on another "twist" in live axles incorporating the twist beam (ever so popular with small fwd) and an independent diff.  I have not found another car manufacture that uses the twist beam and a differential to drive the rear wheels other than Suzuki's SX4.  Please see the embedded links, I love Edmunds suspension walk through articles!  I'm sure Suzuki did this to offer a simpler solution in manufacturing for fwd vs awd variants (it is offered both as awd and fwd in US, my first post was incorrect).  Its interesting to note Chrysler's solution for the early AWD Caravans of taking the dead solid axle  hung with leaf springs and adding an independent diff to the chassis in similar fashion as Suzuki did.  I guess clearance for a pumpkin on a typical live solid axle hung with the same leaf springs wasn't available.  In case this topic starts to wonder around fwd vs awd and leaf vs coil, the above info is just reference.

On to the questions:  Does anyone have additional info on other factory cars specifically with a live twist beam axle?

Another is if instead of swapping to a live solid axle in fwd to rwd conversion, has anyone kept the twist beam, drilled out the hub mounts and added the components to do what Suzuki has done?   

Finally, would anyone consider this over the popular DeDion or solid axle choices in a Locost (or even a Challenge car)?

There was a discussion on IRS vs live rear axles in this thread:

https://grassrootsmotorsports.com/forum/grm/suspension-mythbusting-solid/136022/page2/

I described the 'floppy D', a variation on the DeDion approach that employs a torsionally compliant beam, distantly similar to twist-beam.

Classical DeDion beams tend to be rather heavy, being stressed in bending

I asked if anyone knew of a production car having twist beam combined with driven axles, no one responded.

So thanks for posting this example, it shows what can be done with some clever packaging.

In reply to junked :

I don't have much to add to the discussion, but the SX4 was definitely available as FWD only here in the US.

I can tell you that Saab 9-3 (99-02 at least) have twist beam rears with bolt through rear wheel bearings. Take out the wheel bearings and you are left with nice big holes to run your axles through, and a flat plate to bolt your wheel bearing to.

In that Suzuki though the twist beam is much more 'upright' to clear the diff. In the Saab the rear trailing arms are basically parallel to the ground.

According to wikipedia some honda AWD Fits had a rear DeDion setup.

The SX4 was available in both FWD and AWD in the USA.  Some flavors of the SX4, like the Sportback, were FWD only.  I've seen a number of SX4's that were AWD.

I guarantee the SX4 came in AWD. There's one sitting in my driveway.

In reply to freetors :

Thank you freetors, using Honda Fit AWD in the search gave me something to chase!  Hopefully it is ok to copy and post directly from the FitFreak forum for educational purposes (I put the posters name, post date and link in here).   Its not the best picture, but it looks and sounds the same as I was looking for.

02-04-2013, 12:19 AM

Mini_Odyssey

It does indeed appear to be a torsion beam but how it's done is the beam is designed with a bend in the middle to clear the propeller driveshaft (much like how sway bars bends are on rwd cars) and the differential is mounted on the subframe. So it's possible to do a 4wd without independent suspension, I was hoping this wouldn't be the case but it appears so. I wasn't after the fact on 4wd possibility but more of the fact it might open up ways to do a IRS rear suspension but it appears not.

Then I found hints on the Honda HRV having the same twist beam rear on AWD models.  CRV is independent, but the 2nd gen HRV we know in the US shares much with the 3rd gen Fit, so it makes sense this is probably the next thing to chase in my search.  The quick search I have done so far doesn't have much in the way of visuals and the public view of this design is a manufacturing cost reduction and performance negative.  I agree with the manufacturing part, but in real world practice, I see this as the same argument fwd enthusiasts have touted for decades with the negatives as or as not critical based on the application.   I attached a parts diagram of the twist beam itself in the HRV to show the holes for hubs and the bend for driveshaft clearance.  There were a few under car pics, but I couldn't make out the details well enough to add here.

In reply to pres589 :

Thanks, I fixed my original post.  Using the twist beam for both fwd and awd is an "interesting" compromise for manufacturing and design within the same chassis.

Appleseed said:

I guarantee the SX4 came in AWD. There's one sitting in my driveway.

Ahoy fellow SX4 owner!  How are you finding the ownership of your Suzuki? 

junked said:

Finally, would anyone consider this over the popular DeDion or solid axle choices in a Locost (or even a Challenge car)?

Probably not.  Using components intended to have significant flex as structural suspension members is generally not going to benefit performance.

pres589 said:

Appleseed said:

I guarantee the SX4 came in AWD. There's one sitting in my driveway.

Ahoy fellow SX4 owner!  How are you finding the ownership of your Suzuki? 

Roommates. She loves it. I think the manual trans multiplys the fun factor.

The Buick Encore/Chevy Trax also uses this style setup. Seeing as they are a lifted Sonic with AWD, they just reuse the Sonic's twist-beam rear axle

Appleseed said:

Roommates. She loves it. I think the manual trans multiplys the fun factor.

I could totally see that.  Mine has the six speed as it's a later first-gen SX4 and it's not the greatest shifting trans, especially when cold.  I also wish 6th gear was longer.  I like the car okay but I admit to having Golf envy but would hate to risk giving up the reliability; my car has been like an anvil and needed nothing but basic / normal maintenance for the 50k miles I've had it.  This coming summer I'm probably going to throw a bunch of suspension parts at it to freshen it up.