Courtesy of the folks over at Allpar we know more about the actual body structure of the JL Wrangler.
The name of the game currently is fuel economy, and early on it was rumored that the JL would switch to a full aluminium tub, riding on a hydroformed steel frame. However Sergio Marchionne said back in May "I think we can do almost as well without doing it all-aluminum,”and still meet fuel economy targets. The hydroformed frame is likely to stay as the process is already used by RAM Trucks.
Allpar claims where the real weight savings will come from is changing the configuration of the JL's top. Because Wrangler has always offered a soft top and folding windshield the body itself has needed extra bolstering to resist torsional forces, exacerbated by the rigorous life some Wranglers lead. Looks like the top 'roll' bar will also disappear in its current format.
Allpars source writes:
he traditional soft top is gone. It appears to have removable soft panels over the substructure. The sport bar design gone. It even appears to have built in grab handles.”
“The taillight design will change (my guess with an "x" design, such as the one used in the Renegade), bumpers are mostly the same as current (good for the aftermarket), as well as the tailgate construction [and] 5x5 wheel bolt pattern.”
If this comes to fruition Jeep will be able to remove a good chunk of weight needed to reinforce the lower portion of the body. This will give the JK two advantages, a lower CoG and improved fuel economy.
That doesn't mean the JL won't offer a removable top, just that it won't be the one you know and love.