Rust protection guide

I-81, I-690 and Brine: How Syracuse Commuters Can Slow Underbody Rust

By the Syracuse Undercoating team · October 31, 2026 · 3 min read

If you commute on I-81, I-690 or the Thruway in winter, your vehicle's underbody is getting a daily dose of brine. Here's what's happening and what helps.

Why highways are worse than city streets

Highways are treated early and heavily, and speed throws spray higher and farther. At 65 miles an hour, tires fling salty slush onto the frame, fuel tank, brake lines and rear suspension. A slow city commute doesn't produce nearly as much spray.

Brine clings

Liquid brine sticks to pavement and to your underbody. It mists up from tires and clings to everything, then stays wet in cracks and joints. Because it goes down before storms, your vehicle can be salty even on dry days.

Parts commuters should check each fall

Brake lines and fittings
Fuel lines and tank straps
Rear frame sections and spring hangers
Exhaust hangers and heat shields (for rust, not for coating)

What helps

An oil film (wool wax or Fluid Film-style) on the frame, lines and mounts, applied before winter.
Underbody rinses after big storms when temperatures allow.
A yearly inspection of lines, hangers and the hitch.

None of this is exciting, but all of it is cheaper than a rusted brake line at 65 miles an hour. Call or text for a straight answer on your vehicle.

Want a straight answer about your vehicle?

Call or text Syracuse Undercoating with the year, make, model and town. We'll tell you what we'd do, and what we wouldn't.

Call (315) 555-0146 Text a Question