Discover the Difference: Comparing Lexus SUVs & Crossover Design
Understanding the differences among the five Lexus SUVs can make car shopping even easier. Here’s one way you can find the right vehicle for you and your family and discover the difference in Lexus SUV design at the same time. Keep reading below…
Lexus SUVs have two different frame types: body-on-frame or unibody. Each has their own unique advantages for various driving conditions and by answering a few key questions, you can narrow the field and find the right SUV or Lexus Crossover. Those key details to explore include the Lexus SUV/Crossover Frame Types, Drive System Types and ultimately the Lexus Design Choices that match your needs.
Lexus SUV Frame Types
Lexus body-on-frame models are engineered to be driven both on and off-road and have more in common with trucks than cars. Both the Lexus GX 460 and LX 570 are body-on-frame SUVs and both are built with standard full-time 4WD. So what exactly does body-on-frame mean? Lexus starts with a ladder frame which looks like one big ladder. Two symmetric beams, called rails, run the length of the vehicle and have several crossmembers (ladder rungs, using the ladder comparison) running between them. The engine, transmission, suspension and other equipment attach to the frame to form the vehicle chassis. The actual body of the SUV is assembled separately and then bolted to the frame/chassis, hence the name body-on-frame.
Lexus unibody models can also be taken “off-road” but they are more like cars than trucks. The unibody design consists of one or more stampings that make up the floorplan. Other stampings that form the side panels, fenders and roof are welded to each other and the floorplan with the final result being the vehicle’s body. With the unibody design there is no separate frame: the welded-up body is the frame, hence the unibody name. The Lexus UX, NX and RX are all unibody SUVs and commonly called crossover SUVs.
Lexus Drive System Types
If added SUV performance is important, you may want to consider the AWD, Full-Time 4WD or Electric All-Wheel Drive available on the various Lexus SUV types.
The Lexus Active Torque Control All-Wheel Drive (AWD) system is designed for on-road use and is often referred to as “All-Weather Drive.” The Lexus NX 300 AWD, RX 350 AWD and RX 350L AWD all use the Lexus Active Torque Control AWD system. What exactly is Active Torque Control AWD? Lexus explains the system here:
Engine power goes through the transmission and then into a transfer case. There are two output shafts from the transfer case, one shaft going to each axle. At the front, the drive shaft is always connected to the front differential. At the rear, an electronic coupling containing a clutch package can connect or disconnect the drive shaft and the rear differential. The coupling continuously adjusts the torque distribution from 100:0 (front:rear) to 50:50 or any ratio in between.
Lexus information current as of January 2019 and Subject to change.
Under normal driving conditions, the advanced system all but disconnects the rear axle via the coupling mentioned above, sending some of the drive torque to the rear wheels which a huge plus for fuel economy. On the flip side, when sensors detect wheel slip or certain other conditions (like icy roads), the coupling engages the rear axle by sending some of the drive torque to the rear which benefits control. The driver can also control the system by pressing the LOCK switch to lock the coupling and ensure a 50:50 torque distribution. This is beneficial in maintaining control when first starting off and when the driver knows that the road is covered in sand or snow, for example.
Full-Time 4WD is standard on the Lexus GX and LX and designed for on-road or off-road driving. Engine power goes through the transmission and into the transfer case which includes a switchable set of gears. The high range gear spins the output shafts (to the axles) at the same speed as the input shaft that comes from the vehicle transmission. The low gear range in the Lexus 4WD system is a reduction gear that causes the output shafts to spin slower than the input shaft. Low range has two benefits for slow, challenging off-road driving conditions:
- The driver has enhanced throttle control because a given throttle change produces much less speed change.
- The reduction gear multiplies the available torque, so the vehicle has added capabilities for overcoming obstacles or taking on steep inclines or declines.
The Lexus Full-Time 4WD System incorporates a Torsen center differential within the transfer case and has two functions:
- It accommodates the axles when they have different spin rates.
- It continuously moves drive torque to the axle with better traction.
Of course, the 4WD system is not lost under normal driving conditions either since the center differential has a 40:60 (front:rear) torque distribution, promoting a familiar rear-wheel drive feeling. The smart system will split seamlessly between 30:70 and 50:50 as it senses axle traction changes, keeping you in control and promoting better grip.
For off-road enthusiasts or anyone wanting to take their Lexus SUV on challenging drives, the driver can press the LOCK switch to lock the center differential and ensure a 50:50 torque distribution. Why would you do this? Locking the center differential benefits control when in situations that favor stable and continuous torque, such as when climbing up rock fields (for anyone wanting to take on a mountain in their Lexus SUV).
Electric All-Wheel Drive
Finally, the Lexus Electric All-Wheel Drive system is specifically designed for on-road use and is found in hybrid AWD vehicles including the UX 250h AWD, NX 300h AWD, RX 450h AWD and RX 450hL AWD. The overall principles and feature benefits are the same as the Active Torque Control AWD system found in the Lexus gas model variations but the method is different. With electric AWD, there is no mechanical connection between the transmission and rear axle so there’s no transfer case, no rear driveshaft and no electronic coupling (this is why you will not see the “typical” AWD button that allows the driver to “Lock” on the hybrid models).
Lexus Design Options
If you want the design of a crossover with flexible cargo space and the peace of mind that comes with all-wheel drive (when it’s needed), then the Lexus NX, RX and UX are all great options and you can match the unibody frame with either Active Torque Control AWD (in the gas versions) or Electric AWD (for hybrid models).
The Lexus GX and LX both have body-on-frame construction with Lexus full-time 4WD giving it superior off-roading capabilities and competitive fuel economy. These luxury SUVs have everything you need to take on challenging terrains and provides the same peace of mind and Lexus-level quality.
Questions to Ask: Finding the Right Lexus SUV
- Will this vehicle be a weekend recreational vehicle or your primary vehicle? Weekend users may benefit from the extra cargo and towing capabilities of the GX and LX, whereas everyday commuters may benefit from the versatility and fuel economy found on the UX, NX or RX which are generally easier to maneuver in and out of traffic.
- How many people do you plan to travel with you? The UX, NX and RX seat up to five passengers where the RX L and GX can seat seven and the LX can handle up to eight.
- Do you plan to tow? The NX and RX, being unibody designs, have car-like tow ratings (1,500 to 3,500 lbs respectfully) whereas the GX and LX, being body-on-frame designs, have much higher tow ratings (6,500 to 7,500 lbs). We do recommend towing anything behind the UX.
- What are the on-road conditions that you typically drive? If you typically drive in wet, icy, snowy or sandy roads, then you will benefit from either the AWD or full-time 4WD system.
For more information or to test drive the Lexus SUV model line up, contact North Park Lexus at Dominion in San Antonio, Texas.