GM may end truck-based SUV design

Sharp increases in demand for more fuel-efficient vehicles has seen customers ditch cumbersome fullsize SUVs in droves. For years, American carmakers had a stranglehold on the market for gas-guzzling SUVs and pickups, but as sales dwindle and market share continues to erode executives are keen to develop a new range of lighter and more efficient SUVs in the hope to bring some of those customers back.

One solution that’s quickly gaining favor in Detroit is to develop new SUV models based on car-like ‘unibody’ designs. GM has been building passenger vehicles based on its pickup trucks for close to 70 years but according to latest reports this practice may soon come to an end.

According to Bloomberg, GM is designing lighter replacements for its fullsize SUVs such as the Chevrolet Tahoe, GMC Yukon and Cadillac Escalade (pictured) without using heavier pickup-truck frames. The Tahoe, for example, has been based on the Chevy Silverado pickup since its introduction in 1965 but its replacement – due in 2012 – will likely feature car-like construction.

Unibody construction relies on a frameless shell and is used to build most passenger cars and some small SUVs. Unibody vehicles are usually lighter and offer smoother driving than frame-built truck designs but they often can’t tow as much. For that reason, GM will keep same frame-on-body vehicles. Another problem with unibody design is that it’s harder to share components across different model lines.