Browsing through the archives there doesn't seem to have been an underseal thread for some time, so...

My classic import needs under treating as it has never been done. There are a few small areas of surface rust but mostly it's very good indeed

I like the idea of a clear wax as the original can still be seen, but this is not a must

So, I'm planning on a thorough steam cleaning and then applying one or a combo from the thread title - what's the general consensus

Thanks

 

WURTH underbody seal,can't beat it as it doesn't dry out like other cheaper brands.
Perfect protection for the underside of any vehicle

 

I have used dinitrol and found it good but the car in question isn't used in the winter. But if it had nothing on then I would treat all rust then put on a good zinc primer then follow this up with some stonechip. Then just use the wax treatment in unaccessable areas.

 

I think Waxoyl and Hammerite have a tie up agreement and products. Dinitrol seems to be the brand that all the classic car mags rave about.