Front sub frame corrosion

Zailorman · Post by **Zailorman** » 03 Jun 2025, 10:25

I have just taken off the underbody tray to change the engine oil for the first time since I got my 2007 Mk3 V70. The first thing I noticed was a hole rusted through the front sub frame!!! The hole is in the right hand rail but the rest of the sub frame doesn't look much better. I see that there are a number of subframe assemblies for sale on ebay so I guess this is a common problem.
My question is, are there any posts regarding changing the sub frame? It looks like a fair job that would probably need a ramp. If it is a garage job what would be the labour costs?

Zailorman · Post by **Zailorman** » 03 Jul 2025, 11:36

Just an update . I bought a new sub frame for £380 and the local garage fitted it for me and charged £275

Post by **BlackBart** » 03 Jul 2025, 13:38

Are you in a wet and rusty area? That seems awfully soon for rust-through.

Post by **scot850** » 04 Jul 2025, 10:37

Plymouth is where the pilgrims sailed to the US from.......so yes it is salty in that area.

Having said that, when working on my friends P3 S60 (2012) I was amazed at the level of corrosion on his front subframe. They don't appear to be very well protected.

Neil.

Post by **rollin_home** » 08 Jul 2025, 04:38

I’m recently noticing the rust on the underside of my 2011 xc70 and have started applying Fluidfilm using the spray can and a brush. Advocates of fluidfilm say it penetrates and creeps on the steel and rust and lasts 1-2 years. It’s got lanolin in it so smells like wool!

Maybe I’m too late and should have been applying FF years ago , but will certainly continue on my newer vehicles.

Post by **abscate** » 27 Jul 2025, 18:00

Plymouth is where the pilgrims sailed to the US from.......so yes it is salty in that area.

That’s amazing! They landed in Plymouth, too!

Home of Rock Auto, no doubt.

Post by **scot850** » 05 Aug 2025, 16:19

Neil.

Post by **scot850** » 05 Aug 2025, 16:22

I've started to use Fluid film on my cars due to the level of corrosion from the de-icing agent they use here in the winters. It does not go hard and stays flexible. The road dust helps as it builds up on the outside of it and adds another protective layer. Takes me back to the days when we used our old engine oil on the underside of the cars. Can't see why they don't advocate for that anymore?

Neil.