4th gen Fuel economy and general driving impressions.

GSLV6 · July 2

Speaking with Lexus, it appears changes to the power pack on the v6 included some enhancements to Battery efficiency over the previous gens, plus the revised V6, to comply with tightening EU emissions regs resulted in both port and direct injection (clever move because it won't suffer the carboning up issues of direct injection nor the gas dilution of the oil resulting in more frequent oil changes being recommended) I was keen to compare longer term fuel efficiency.

Most of my driving is done in normal mode, with a switch to Sport S+ for B road twists and turns. My previous F Sport managed a long term average of 28mpg (hilly area, mixed driving) with 32mpg being about it at 70mph M/way cruising, and the max I saw was 36mpg cross country on a 150 mile trip.

The newer power train combined with improvements to drag coefficient with the more slanted front and rear screens have indeed seen a substantial improvement in overall fuel efficiency.

A recent 250 mile round trip on motorways saw 37mpg and it's achieving roughly the same on cross country A roads, with shorter local trips up from 28 to 34mpg. That's a whopping 6pmg more than previous generations. It doesn't sound that impressive until compared with similar sized diesel suvs. A friend has a diesel X3 and he manages an average of 35mpg, so the last of the V6's actually betters to BMW diesel models. Impressive stuff.

Performance-wise, the newer model has the older one licked as well, with mid range shove in Sport S+ being particularly impressive given the total absence of any CVT lag a with other modes, along with max power available from the electric motors instantly.

The more that I drive the 4th gen, the more I like it. It lacks the all round visibility of older models and still doesn't feel as sporty or nimble as the overall balance of the Gen3 F-Sport, but to any naysayers who consider the F-Sport as a styling only exercise, think again....with adaptive stabilisers (dampers) and the S+ pack, the 4th gen is more definitely sportier to drive than standard or Takumi models without the same set up and packs an impressive punch when asked. Lexus have produced a gem in this model. Newer RX500+ models may be quicker still but my short acquaintance with one of those and with an RZ convinced my that the interior trim and finish on the 4th gen seems to have newer models licked on quality of interiors and little practical touches like the retention of the hinged door buckets.

The not so good changes: Interior load space seems less (despite the figures) due to the increased rake of the rear door; the valve covers have gone from steel to plastic (although I've yet to hear of any issues with the RX covers) and the engine bay isn't as neat and tidy plus the newer F-Sport wheel spokes are more prone to being chipped as they protrude a longer way out than older 19 inch F Sport spokes. I also miss not having a manual door lift at the back but somewhere in the manual I think I read that the motor can be bypassed in the menu system to allow manual opening. Other than these relatively minor points, the 4th gen is a triumph of design and quality. The ride quality is particularly impressive. Quieter, more refined and smoother...at last it feels every bit the prestige model to drive that it always ought to have been.

KzA · July 14

I avged horrible MPG on my 4th Gen RXL. It is usually 28mpg to 30mpg. To be fair, I am usually the one passing. On the Autobahn it was like 19mpg at 120mph. If I average 80-90mph, it is like 26mpg. I have also driven the UX250H and I averaged 49-50mpg with the same driving style. On a road trip, friend with a diesel Maserati averaged 35mpg (also very fast driving). I am not fan of diesel and will never get one but just posting figures as a frame of reference.

Ken R · July 14

I'm getting up to 52mpg on a long run (incl motorways) when running the 5th Gen RX450h in HV mode which is impressive given the size and weight of the vehicle.

GSLV6 · July 15

I am surprised that there's any surprises that a 2.2 Tonne RXL only delivers 19mpg on "120mph autobhan" runs. Hardly real world average and that's been driven close to flat out! Combined average for mine is low to mid 30's which is about the same as the BMW X3 diesel my mate runs (he averages just under 35 combined), so I'd say that was as good as you could expect from a 3.5 litre 2.2 tonne brick.