Waxoyl washes off easily. Dinitrol does not and performs far better in tests and in real life. If you buy several spray cans of Dinitrol 4941 (for underbody as opposed to cavity ) sealing, there are discounts - see ebay for cheapest prices.

I keep our 2004 Yaris perfect underneath using Dinitrol every 3-4 years...Underneath is rust free. (As is the exhaust - but using heatproof paint)

Edit Dinitroled the underneath of a 2004 VW Sharan where all teh paint had vanished around the boot floor and rear suspension pick up points.. Used a pit. Took 4 cans and 90 minutes.

Edited by madf on 06/02/2018 at 11:52

I had a Talbot Horizon in to the garage for work a few years ago,

put it inside and locked up for the day,

Anyway open up next day and was struck by a line on the floor either side of the car under the sill!

A quick bit of investigation revealed it looked/smelled like old sump oil!

Anyhoo it was in for Mot worked and if I recall it needed a brake lamp bulb or similar small stuff.

Which I'll admit was a bit of a shocker as these were rust buckets,

Real cheese graters underneath.

So owner turns up and he's pleased with the little I charged him but before he drive off I'm like "what's the thing with the wierd oil leaks"?

And he states it's an old trick from where he comes from,

One of the Skandinavian countries,Can't recall which one but it really snows up there.

They spray into the sill cavities with oil that's been drained from the sump during servicing.

Now this car was old back then and I'd take a bet that barring accidents it's still on the road now,

And as I stated they were rust buckets,

All I had to do was get a Mot failure in and my rent was paid for a month.

All he had to do was keep spraing the oil in.

And It's not a messy as I'm making out here.

Just a few drip/drops on my clean garage floor.

You wouldn't have noticed it out on the tarmac.

Now that to me is both preventive maintinance and recycling!!

Ye I bet in scandavia there's loads of salt in the roads all the time.

In the summer I think I will give the underside a quick rinse with the hose and paint some waxoyl or motor oil. If it can protect against the harsh Scandinavian winter should be good enough.

Dinitrol looks much better but I'd need to rent a steam cleaner and it's expensive I want something that's cheap and easy.

If any problem areas do develop I might clean with water and engine degreaser and put a bit of Dinitrol on just the problem area.

Edited by Ebob on 06/02/2018 at 20:59