After owning the car for 3 years I have noticed that my IS200 is starting to use the coolant, the level dropping, my oil and coolant is clean, no mayo.
Its probably always been like it, I may just be taking notice now.

Does anybody elses? do you have to top up and how often?

This goes out to stock and tuned engines.

mine uses about a pint of water every 2000 miles but not sure where it goes as the water pump is nice and clean and no mayo?

that was going to be my next question, if this is normal, where does it all go?

I always top up using Halfords ready mix.

Mine seems ok, just top it up every now and again but nothing major.

Stav

Check the by pass pipe above the waterpump. The 'o' rings on the by pass pipe can perish over time causing coolant loss.

Thanks, will get on that one, I have not noticed any coolant stains.

err you shouldnt be using anything other than Toyota Red stuff..

Never check mine. Just topped up 300ml after 3 years( 60k service), on recommendation at the service, make sure coolant reserve is in the middle (behind the radiator).

I also had my bypass hose replaced under warranty shorty after getting the car.

Why?

My Lexus owners manual says "Coolant Type : Ethylene - glycol coolant (Do not use alcohol type)". Do IS's use a different coolant than other Lexus models, if not, then any ethylene - glycol coolant can be used, including halfrauds own brands.

Mine's hasnt used any antifreeze at all since I bought the car in Sept 2007.

it is red that i use.

I believe its super long life coolant....gets replaced every 60,000 miles

Noticed that the coolant is dropping when im not driving (when its cooling down on its own) also noticed when car was ticking over that its loosing it from the lower pipe on the radiator/overflow pipe (may just be because level was close to max).

Have i read before that radiator seals are not good, I have used them before on previous cars.

How true this is.apparently if you fill the coolant up 2 the max when it gets hot it expands hence will come out of the overflow pipe coz its a sealed system and has no expansion tank for it to over flow into....as long as its between the max/min marks should be ok.................................................just check were the level is when its hot when mine is hot the level sits at the max level.........

i sometimes get a bit of the pink/red coolant at the top of the overflow /filler cap......dno why or what the problem is doesnt seem to be any rubber o ring or anything just plastic cap that snaps/clips on...

i have recently changed from my TRD radiator cap, a higher pressure cap, dunno if this has anything to do with it, i wouldnt have thought it would???

my coolant never moved its only just starting to do it, i have used 3/4 litre topping up over the last couple of weeks, i have only been driving it at weekends, again that might be the problem, not driving it enough.

When I bought my car I had noticed it needed a top up every 3 weeks or so. I had a word with my neighbour about it who also has a IS200 and he has the same problem. I swiftly popped down to Halfords for a bottle of radweld, poured it in topped up my levels and haven't had a problem since!! It's been 5 months now (5k) and its still holding fine. Give it a go!

oh dear shouldnt use products like radweld/radseal in modern cooling systems

Update: Car been in today to my local garage, they have located a leak from the radiator, sooo new rad has been ordered and being fitted next week, damn radiators are pretty expensive.