johnatg

So - why do I think that the fuel economy of Lexus GS/IS hybrids is more down to the CVT gearbox and less to the hybrid power train? That's not the popular perception of hybrid cars but that's because of politics and marketing. Let's like at what fuel consumption is - it is based on the transfer of chemical energy into kinetic energy in the vehicle. In hybrids, regenerative braking and spare engine power transfer some kinetic energy and chemical energy (petrol) into chemical energy in the traction battery. That can then be used later to boost the kinetic energy in the vehicle, either by reducing the amount of petrol needed at any one time or to add to the power available from the engine to aid acceleration. But the hybrid battery capacity is very small and you can watch its power reserve plummet quickly when called on for acceleration. (And equally you can watch its power available increase rapidly - even from near empty to near full when descending even a small hill.) The amount of petrol being used at any one time depends on a number of things - the capacity and design of the engine, throttle opening and engine revs. Politicians and the green lobby want us to reduce the amount of petrol consumed and car manufacturers have gone about building this requirement into their ice vehicles in various ways. Current fashion is to use every small engines, which intrinsically use very little fuel on cruise. But then they add forced induction (mainly turbo charging but also supercharging or both) to increase power when needed for acceleration. Mondeos (RIP) and Range Rovers with 1 litre engines, anyone? I suspect that long term durability is very much an issue. Lexus took a different approach - use a relatively big old lazy engine and run it at low revs and small throttle openings. You don't need much power (and therefore petrol) to trundle a vehicle along at 30 mph - my wife's Seat Mii runs at about 1750 rpm at 30 mph - (that's not even on the power curve even on its little 1 litre engine) and is probably making about 20bhp or less. That's all you need - a GS is going to need a bit more but not much, until you open the throttle to accelerate and then the revs go up and the petrol starts pouring in. See current fuel consumption on the dash display! It's true that the amount of petrol required at that point is reduced by the boost available from the hybrid battery, but see the comment about how small the hybrid battery capacity is. The revs all depend on gearing. The great benefit of a CVT gearbox is that it's always in the 'correct' gear. If you engage S mode on a motorway you can observe your engine revs - and you will find you can cruise at 70mph at about 1700 rpm on a level road. That is remarkable and not achievable with a manual or normal automatic gearbox unless you had many more available gears than is practical. (Not many people would want to drive an 18 speed manual as in Australian road trains etc) But at 1700 rpm and a moderate throttle opening you are using very little fuel - and that is why CVT gearboxes enable impressive fuel economy. You will observe 50-60 mpg instantaneously in cruise. At 70mph on a motorway the hybrid battery is doing little or nothing - but it will help some when you come to a hill or need to accelerate after a slow down. Meanwhile, more recent hybrids (and plug-in hybrids) have a large capacity traction battery and can achieve substantial range on that battery. The GS and IS hybrid ranges are now 15-20 year old designs (from the drawing board) - you might argue that the origins are even older in the Prius. Electric vehicle technology has moved on by leaps and bounds so I'm afraid our cars are now rather outdated (but well proven technology). Which isn't to say that I won't be keeping my car for a long time yet!

I think that's about right. I get in the range 36 - 42mpg - the higher figure on long motorway runs. It's a big heavy car - I don't know that you can reasonably expect much more. The battery is pretty small by current hybrid car standards - the range on electric is very small - less than 2 miles and only at slow speed. The hybrid/traction battery is there to boost acceleration. Incidentally my view is that the fuel economy is down to the CVT gearbox, not the hybrid power set-up. For the size and weight of the car, I think you would be lucky to get 25-28mpg with a normal ice petrol power train, so to get 50% more is pretty good really. I'll expand on that sometime and explain why I think that and what my evidence is.

There's nothing special about Lexus aircon. Any competent operator with the correct machine can do it. Google Groupon ats aircon and get a voucher to have it done by ATS Euro master for £37.99. Check that an ATS branch near you is accepting the coupon - not all do. Offer may expire soon.

October to December

Somewhat surprisingly, there are more Mk 4 GS450h Premiers (~275) like yours, Robert, than GS300h Premiers (~240) The majority (161) of GS450h Premiers were registered in 2012/2013 then very few each year after that (25, 25, 35, 17, 11, 3 up to 2019.) Numbers approximate and net - some were clearly destroyed!

There were only 13 GS300h Premier registered in 2013 (all in Q4). There are currently about 240 Premier versions registered in UK. (all years 2013-2019) I've got one (2014, Reg December) Meteor Blue.

Those are four very different cars, each with their advantages and disadvantages. Might be good to investigate to match what you want. Most for sale in UK are advertised on Autotrader.

It sems to me to be a bit odd to lump all those service items together. If you stick to the recommended intervals you don't need them together - eg Air filter (Interval 40K miles), Plugs (60K), Coolant (100K then 50K). If my arithmetic is correct the first time you need them all is at 600K miles! I suppose if you bought a high mileage car with no service history you might want to do the whole lot and start again. And oil. Nearly £150 for 7 litres? Come on - buy 10 litres and keep the 3 and a bit for next time. Anyway, there's a lot of nonsense written about oil. If it meets the specs, that's all you need. Maybe one brand is 'better' than another - but you won't notice. I used GM Dexos2 over several years but I've recently switched to Mannol. I've been thinking about what to do about my GS300h major service, due imminently. Lexus want £630 - it takes them about an hour to do (a couple of years ago I had it done while I waited at Lexus Stockport). What I have done is bought 5 Litres of Mannol 0w20 Legend Ultra, 2 Blue Print Oil filters (a deal - one for next time) and a Blue Print Carbon Pollen filter all for less than £45 (BTW Nothing wrong with Blue Print - I've used them on and off for the last 30 years with no problems. They are part of Febi Bilstein these days) (My GS300h only needs 4 and a bit litres of oil) I don't get the Lexus warranties 'tis true, but I've got nearly £600 in my pocket. And I still enjoy doing my own spannering - at least I know it's been done correctly! YMMV!

I think you misunderstood what they said. Larger wheels give a worse ride (not because of the tyres - because of the size of the wheels) Lower profile tyres cause a worse ride (less rubber and air to flex) Two different things but they work in unpredictable ways in conjunction. The design of the tyres plays a part too. And ride is not just down to tyres - the suspension design, shock absorbers and springs all play a significant part. All relative to the weight of the car. So there are lots of different factors at work. Altering one or more may have an effect, but it may also have consequences - eg softer (lower pressure) tyres - slightly better ride, higher fuel consumption, lower grip. Softer springs - softer ride, worse handling. Ditto shock absorbers. It's a compromise between lots of different factors.

Drive each window up and down with its own switch - ie the one on the door, not the switch on the driver's door. Pause holding down the switch when the window is fully closed for a couple of seconds.

My GS300h premier has 18" wheels with Goodyear Eagle F1 tyres. I would describe the ride as acceptable - firm but not amazingly insulating from road structure - potholes etc. It's not the best feature of the car - the ride is not comparable to Jaguar XJ, for example. But you'll get used to it. Every car has its pros and cons and the Lexus has more pros and fewer cons than most comparable vehicles.

You're paying about £200 for the spark plug change but they don't need doing until past 60K miles It is ridiculous to change plugs based on time. If they will do the warranty without the plug change you'd be quids in.

That's strange - my IS250 (2006) definitely had an alloy sump. I always used the Smartearlybird fibre/aluminium washers and continue to do so on my GS300h (also alloy sump) - no problems at all.

Re the ATS/Groupon regas deal - I had my wife's Mii done last week. If you haven't had your aircon regassed in the last 2-3 years, it's an excellent opportunity. ATS normally charge £62 so the Groupon deal at £38 is great value. The gas does leak out and the aircon gets less efficient over time. Be aware that not all ATS branches accept the Groupon voucher - eg Knutsford doesn't but Macclesfield and Altrincham do in my locality

The thing of it is - it's not that easy. You have to remove the back seat to get to the traction battery isolation plug (I think it's that orange thing on the face of the battery in the pic below) And is that enough anyway? Could you still fry something in the hybrid electronics by electric welding even if the battery is isolated? I suspect that the garage is going to find out the hard way that welding on a hybrid or electric vehicle is not as straightforward as welding on an ICE car where it's easy to disconnect a battery terminal

The battery space is exactly the same on GS300h as GS450h, so yes - they will fit.

OP was misled by the forum description. It says 'Lexus 450h' Mods - can you change the forum description to say GS450h and what about GS300h? Or just have Lexus GS ? Thanks!

Check this: https://www.ebay.co.uk/itm/163090823963?fits=Car+Make%3ALexus&epid=13039424755&hash=item25f8f87b1b:g:D6UAAOSwirFbHScb

OK to drive with the aircon off.

Compressor seized?

Can't really comment on a comparison but the is220d has a poor reputation here. The Insignia diesel has a fatal flaw to do with an o-ring in the oil pick up from the sump. You don't know there's a problem until the oil pressure warning light comes on by which time the engine is wrecked. Which is why there are so many cheap Insignia diesels about. Cheap fuel? Can't compensate for the costs involved in fixing engine problems. Fuel cost for an is250 is nothing like double the diesel - in fact quite similar now, I'd say.

Nice as it is to have an unusual feature, I think at this point I'd be looking at what would be involved in getting it to non-steered rear suspension spec. Just a thought!

At least you would avoid the probably huge Lexus UK (or wherever) markup. Might take a while to ship though esp as they're shut for a hol.

That would do the trick. Or you can get readers which connect to your phone via Bluetooth, then you use the app 'Torque' to read codes and get other info. In the meantime, try changing the battery in the key. That is sometimes the cause of 'Check VSC'.

Come, come - that's unnecessarily pessimistic. That engine will do 250K miles or more. Even if it does burn a little oil along the way.