How much frame rust is too much on a GX460?

The short version

Surface rust is normal

A light orange coat is normal on any GX that's seen road salt. The PPI on mine found some, and the shop called it fine.

Rot means walk away

Rust that flakes off in layers or has holes is rot.

The hammer test

Tap anything that looks bad and prod hard-to-reach spots with a screwdriver. If chunks fall off or the tool goes in, walk.

Compare within the region

What passes for normal in Minnesota would look rough in California. Judge a truck against others from the same region.

Rust costs you later

Even on a solid frame, rusty bolts seize and snap, so every repair takes longer. Price that into the offer.

Protect yours

If you drive on salted roads, have it undercoated by a well-rated shop near you.

What I'd use

Blaster Surface Shield, because it came out on top in RepairGeek's side-by-side testing.

Where owners split

On r/GXOR it's Woolwax vs. Fluid Film. Both have fans, and both are messy.