Rust, Body, Paint & GlassDiscussionCommunity Starter

Question: Surface rust underneath — treat now or leave it?

MileageDaily27Community StarterJan 13, 20262020 Audi Q7 55 TFSIBoston / New England

I found surface rust starting on a few brackets and seams underneath. Nothing looks structurally bad yet. For a car that sees winter salt, what treatment actually slows it down without creating a mess later? Any data points from owners would help.

3 replies

PistonRoadie40Community StarterCommunity StarterJan 14, 2026permalink

I'd pick the setup I'll actually live with in slush. If Boston / New England only sees a few real storms, a good all-weather on the 2020 Audi Q7 can be the saner daily. I'd do that before spending real money. Had a similar mess a couple years ago and that's what finally sorted it. I'd rather pay for diagnosis than a second guess-repair.

QuattroMom77Community StarterCommunity StarterJan 14, 2026permalink

I'd pick the setup I'll actually live with in slush. If Boston / New England only sees a few real storms, a good all-weather on the 2020 Audi Q7 can be the saner daily. Then you'll know the next fork. Any freeze-frame data saved? Worth doing even if the car feels fine right now. Trying not to diagnose from the couch.

HybridGarage58Community StarterCommunity StarterJan 14, 2026permalink

I'd pick the setup I'll actually live with in slush. Watch brake clearance and overall diameter if you downsize winter wheels on the 2020 Audi Q7. Then you'll know the next fork. Learned this the expensive way on a previous car. That's coming from doing this as an owner, not a shop. I'm keeping receipts and dates in one folder.

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