Hi all,
After seeing Mazdatrix's website and noting the lengths and size of hose I need, I have set out to find the hose required (in silicone) to replace all the vac hoses in my car, since I have a leak somewhere and I can't find it, I'll replace everything and hopefully problem solved.

My question is: I can't find 3.5mm silicone vac hose ANYWHERE in Australia that I've tried, the cost of importing it from the US is absolutely huge in terms of postage, and while I am prepared to do that I'm hoping I can perhaps get away with using 3mm hose instead which is cheap and plentiful. I know 4mm is slightly too big which can cause leaks later on which is exactly what I'm trying to avoid. 4mm is also plentiful so as per your suggestion I am prepared to go this route if it is going to be better than 3mm.

Is 3mm OK as a replacement for 3.5mm or am I going to get problems?

Thanks,
Sean

 

I don't really see a problem unless its a pain to fit on there.

One thing you can do is run 4mm line and put hose clamps on it if 3mm won't fit.