Does anyone know the I.D. of the large hose between the PS reservoir and pump? Mine is a little wet on both ends but I don't want to pull it off until I have a replacement hose. The Lexus part is approx $40. I'd much rather spend $4 on a short section of bulk hose. I have an old PS pump from my previous 400 which takes a 5/8" ID (or 16mm) but I don't want to assume the 400 is the same as a 430 since they use different pumps. I think it's safe to assume it's not 3/4"ID, the next inch step larger, but I'm more concerned it might be 17 or 18mm...

I tried measuring but no hard line is exposed and I don't want to disturb the old hose for fear it will disintegrate with any twisting.

Save yourself wasted time, gas, irritation, bad advice, wrong hose, by purchasing the OEM part in the first place.

Don't forget to purchase new OEM compression clamps....worm gear clamps will not work.