KHedges

So I had to replace my old coolant reservoir about a year's worth of driving ago, and got some cheap aftermarket one at a chain auto parts store. I just discovered it's leaking now, luckily a small leak and not catastrophic.

Should I go to the stealership this time, or is 1-2 years the usual life expectancy?

Thanks?

georgeb944

FCP Euro sells the VAG part with a lifetime warranty.

Zaub02A6

I've replaced mine 4 or 5 times in the last 15 years. The problem is that it is part of the pressurized system, so a leak affects the pressure in the entire cooling system.

Last time I replaced mine the increased pressure in the system caused a coolant sensor o-ring to start leaking.. replaced that and then a different one... then the water pump... fun times! At least it was time for a timing belt job anyways.

meternerd

Be sure you're using the correct coolant. Wrong coolant will cause cracks, leaks and eventual failure of most of the plastic parts of the cooling system, including the reservoir. I speak from experience......

KHedges

I'm definitely using the right coolant (R12, Pentosin brand) and correct dilution.

Thanks for the warning about other leaks. I seem to have a small leak somewhere because the coolant level dropped 1 cm or so since I installed the Febi-Bilstein tank a few days after posting. My friend and I changed the water pump and thermostat about 12,000 miles ago with the timing belt service so those are less likely to be the source.

georgeb944

Your best tool for diagnosing coolant loss is a "coolant system pressure tester," which can be borrowed (deposit returned on return of tool) from places like Autozone. You will also need an adapter for the audi system,

KHedges

Thanks, I bet my friend has one he can lend me.

KHedges

I smelled coolant, checked under the hood, and there's a drip from the lower expansion tank hose. It felt a bit squishy when I worked on it, so I'm not surprised.

Zaub02A6

agreed. I borrowed one from Autozone and it was a life saver. (well, at least a grey hair and swear word saver)