We've known about the eventual existence of the 2018 Lexus RX 450h L three-row hybrid SUV ever since the 2018 RX 350L gasoline version was shown at last year's LA Auto Show. The mechanical details were easy enough to surmise. All you needed to do was compare an existing RX 350 to an RX 450h and then look at the RX 350L on display and extrapolate by adding the same hybrid all-wheel-drive powertrain under its elongated skin.
But that left three questions: When would Lexus start selling it? How much would it cost? What would be the fuel economy?
Today we have the answers to two of those three questions. The RX 450hL AWD goes on sale this April, and, like every other RX hybrid, it only comes in all-wheel-drive form. The base price will be $50,620, plus the usual $995 for shipping and handling. That makes it just $1,550 more expensive than a base-level V6-powered RX 350L with all-wheel drive. The more upscale RX 450hL Luxury AWD will start at $54,555 (plus $995 for shipping and handling), and that's only $470 more than the cost of the RX 350L Luxury AWD.
The picture is a bit less rosy if a hybrid is on your shopping list but all-wheel drive isn't. The base RX 450L AWD with its compulsory all-wheel-drive drivetrain costs $2,950 more than a base RX 350L with front-wheel drive, while the RX 450L Luxury AWD narrows that gap somewhat and costs just $1,870 more than a front-wheel-drive RX 350L Luxury.
You do get a bit more, though, because the RX 450hL comes standard with middle-row captain's chairs instead of the split bench of the RX 350L. Beyond that, the standard equipment and options lists of the RX 450hL mimic those of the RX 350L AWD. Detailed option pricing has not yet been confirmed, but we fully expect those line items to more or less match, too.
In case this is the first you've heard of either version of the three-row RX L twins, the body has been stretched some 4.3 inches to accommodate a power-folding third-row seat, and the rear roofline and tailgate glass are a bit more squared-off in the name of third-row headroom. According to the chief engineer, the RX's third-row seat is intended for occasional use when relatives come to visit, a use case that matches the needs of the typical Lexus SUV customer. But occasional visits by the grandparents is not the only benefit because cargo capacity behind the second row is superior to that of the regular RX 350 and 450h SUVs when the L's extra row is folded and dormant.
As you can imagine, the transformation from RX 350 to 350L results in a longer SUV that weighs more, and this manifests itself in a 1 mpg drop in overall fuel economy. No official 2018 Lexus RX 450hL fuel economy figures have been released, but the familiar two-row version of the 2018 Lexus RX 450h is rated at 30 mpg combined (31 city/28 highway). The official answer to the final question of fuel economy will no doubt come soon enough, but it seems easy enough to guess.