Thinking Of Undersealing My S3 When I Get Her.

m2srt

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As I'm planning on keeping my S3 quite a while (10 years+) I'm thinking of undersealing her chassis as I have no idea if Audi still galvanise their chassis's. Any ideas?
 
How long is the corrosion warranty on the car? My feeling is that if you underseal it with any unapproved method then the warranty will be void...
 
chances are you'll actually make it rust quicker. The multistage processes that the body goes through are state of the art. The places rust starts in are inside box sections and weld joints. The EPD process and inter weld sealants take care of these areas. By adding underseal you may block up drainage areas and trap water in, same as would happen when the underseal delaminates and causes pockets for water and brine to sit in.

I think the corrosion warranty is pretty comprehensive and by adding something you will almost certainly void that warranty. Keep it clean and pressure wash under the wings and touch up paint chips as soon as you find them as that's where corrosion starts and is not covered under warranty.
 
Good advice to keep it clean underneath with regular jet washing, especially during winter months when there's salt about (which remains in the road surface well into summer...). Yes the body is well protected; galvanised steel and underseal but all the suspension components are poorly protected with thin paint and these parts will develop surface corrosion quickly. My last 8P was delivered with corrosion already showing on the front struts... I did protect the entire underside of my 8V from day one with ACF50 fluid. It was developed to protect the US Navy's helicopters operating off aircraft carriers. It's brilliant stuff and I've used it on my motorbike and have never seen any corrosion. It's also clear and therefore not obvious so shouldn't compromise warranty...
 
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Are you planning on keeping the car for the next 10 years??? Seems a tad OTT :/
 
ACF50 is stunning stuff................
 
With the increasing levels of 'nannying' in cars, I somehow would feel uneasy driving round with E-Call, EDD and other things onboard. I know it sounds paranoid but I'm old enough to remember when cars were just cars.
 
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Yes my car is a keeper - at least 10 yrs... Hence I want to protect/preserve it in good condition. My last car - a MKIV Golf was owned for most of its life by a gent who really looked after it but at 10 yrs old all of the undercarriage was very badly corroded. e.g. the brake disc shields had rotted away and were extremely difficult to get off to replace.
 
Cars just aren't built to look pristine after 10 years these days - maybe an exception to that would be Merc S-class/Bentleys etc. My disc hubs had decorative rust on them from almost day 1. Brake disc shields will rot, springs and struts will collect surface corrosion at the very least - your actual car body should remain pretty resilient though. Most cars with good residuals take a real dive in retained value when they hit 5 years old and the dealership network is no longer interested in it for used stock. At that point when they have to compete with other cars, you will not see a 5/6 year old example of an Audi S3 commanding 3x the price of a well maintained Focus ST of a similar age - something has to give.

When you consider how much it is to maintain an old car and how much your 10 year old S3 will have lost in those 10 years, there isn't much in it vs annual cost of running a new one (less than a grand a year in it). Buy a new S3 at decent discount (£30k paid for a £33k RRP model) and it's probably going to be worth £20k after 3 years, it's cost you £3333 a year in depreciation and will have needed to do nothing to it except replace the front tyres and give it 2 or 3 services. Buy a new one for £30k, keep it and have it worth probably £4k at 10 years old, you've lost £2600 a year, will have replaced the brake pads twice and maybe the discs once, maybe a new clutch, probably shocks all round once, maybe a timing belt and a gearbox oil change - it all adds up. 7 years without the reassurance of warranty. There's next to nowt in it. Consider any new innovations that might become standard on newer cars in the 7 years following year 3....

On a new car with exceptional residuals, it usually makes sense to change every 3 years, VAG engineer the financials of ownership to make it so.
 
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