100k Service

Adrian 300H · January 20, 2019

Hi all,

My IS300H is due it's 100k service later this year and I am wondering there is a definitive list which covers the checks and fluids etc that should be completed?

I downloaded the lexus list but there are a lot of "model dependant" items on it which has confused me somewhat.

Just wondering there is anything major I need to keep in mind? Needless to say I'm not going to Lexus for the service.

Cheers.

ColinBarber · January 20, 2019

According to the European schedule there isn't anything that is needed at 100k other than the standard 20k service, but I believe Lexus UK change the engine and inverter coolant at that interval.

Adrian 300H · January 21, 2019

Thanks Colin, I'll make sure to put these items on the list.

On another note my discs and pad need doing on the front, having reviewed the service history I saw no mention of brakes being done so far. So first pad change at 94k miles, that's some going. Picked up the full front set (pads and discs) from lexus Birmingham for 170 pound. Rears seem fine so will wait another while.

Adrian 300H · January 21, 2019

I'm hoping this will also cure the rattle I'm getting on rough surfaces (tapping the brakes cures this) does anyone know if there are clips that come with the pads?

Stuart Aspey · February 13, 2019

I am quickly approaching 100,000 miles in my IS300H. Just clicked over 88,000 this week. The cars previous owner had the first 4 services done at 12,500 mile intervals, which has skewed the servicing points. So, my 90,000 mile car will be going for its 80,000 mile service. All Lexus and they've said this is standard as a result of the first four services. But this means my 100,000 mile service will be at 110,000 miles on the car . . .

Anyway . .

I just wanted to ask whether the 100k service was to change water pump/cambelt belt/auxiliary belts/spark plugs/oil filter/air filter/pollen filter/coolant/oil. The full works. As it was on my previous IS, the first gen? Or is this what is changed at 20K service too?

Kind Regards

Stuart Aspey

Mikey B · February 13, 2019

No cambelt so you can cross that off the list!

Just checked on mine snd the big one looks to have been the 60+ at 120K - that included plugs, but cant see much else beyond the normal full service

Stuart Aspey · February 13, 2019

Thank you for the reply. Cambelt removed from metaphorical list.

Kind Regards

Stuart Aspey

route66 · February 13, 2019

The only other thing I can think of is the gearbox oil. It's not mandatory at this mileage but some say this is when it should be changed.

Having said that, this exact subject has generated lots of discussion and debate for the IS300H - and other Lexus/Toyota hybrids - but I have yet to hear of anyone, ever, getting this changed on the IS300H. You could be the first in the world!

reeac · February 16, 2019

Yes, checking the service schedules for my IS300h, there's changing differential oil every 20k miles but no mention of gearbox oil. Being an epicyclic gearbox it must have clutches to control the distribution of power and hence have friction material which will release wear debris into the oil ....maybe they just have a very good filtration system.

ColinBarber · February 16, 2019

No that isn't how power is distributed. There is a clutch but it is permanently engaged at the flywheel as a protection device but that wouldn't normally slip and wear.

The transmission fluid should be inspected every 40k miles - mainly for level in case there is a leak but quality should be checked too. There is no interval for it to be changed.

If you run the 'severe' maintenance schedule then the fluid should be changed every 60k miles.

reeac · February 17, 2019

Oh. , dear that's got me thinking. If I'm accelerating away from rest at a constant 2000 rpm (my favourite engine speed) then presumably the surplus power is used to charge the traction Battery but what happens when that Battery is fully charged? Does the fuel injection reduce the fuel supplied and hence the power generated by the ICE accordingly? Then there's the matter of accessing and staying in the fixed gear ratios via the paddles e.g. for long downhill stretches How is that done elecronically if there are no clutches?

ColinBarber · February 17, 2019

If the Battery is full then amount of charge can be controlled. Going downhill the engine can be used as a load, being turned over but no fuel used.

The simulated gears are achieved because the electronic control of the transmission can make the engine run at any speed it wishes - the engine isn't directly connected to the wheels.

here is a fun demo of how the transmission works:

http://eahart.com/prius/psd/

There are many videos on the subject, the second half of this video is shows the physical components being rotated to give a good understanding (components are a slightly different design in the 3rd Gen system used on the IS300h but technically work in a similar way):

BigChange · February 17, 2019

Complex mechanics beyond me but thanks for the informative and well presented post and utube video. Must remember to extend my warranty ! 😵

route66 · February 18, 2019

On 2/16/2019 at 2:40 PM, ColinBarber said:

If you run the 'severe' maintenance schedule then the fluid should be changed every 60k miles.

Know of anyone who got it done?

Britprius · February 18, 2019

The engine and transmission coolant ( Toyota SLLC ) change should be done at 120,000 miles or ten years, and the every 50,000 miles there after. There is no recommended transmission oil change. It has been found on the US Prius Chat forum through oil annalist that the oil at 30,000 miles contains much gear ware in metal contamination, and it is suggested to change the oil at that millage, and then every 50,000 miles because the oil looses 25% of it's viscosity. This seems sensible to safeguard the transmission without breaking the bank.
The electric motors are cooled by the oil and run at high voltages "around 600 VDC". It is therefore not desirable to have oil that becomes conductive. Oil becomes acidic when continually heated and cooled. The reason why the oil in high voltage transformers on the electrical supply grid is checked regularly for acid contamination.

John.