Wheel offset (ET) decoder

What does 7.5Jx17 ET40 5x112 mean?

The rim is 7.5 inches wide (J flange) and 17 inches in diameter; ET40 means 40 mm of offset; 5x112 is the bolt pattern (5 bolts on a 112 mm circle). A smaller ET pushes the wheel further out.

Effective offset
ET35
Outer face change
+22.7 mm
Inner clearance change
+2.7 mm

Wheel position visual

Suspension / brake sideWheel arch side
  • Current wheel: 7.5Jx17 ET45
  • New wheel: 8.5Jx18 ET35
  • Hub face · Effective offset: ET35 · Spacer effect: 0 mm

Positive outer change moves toward the arch; positive inner change reduces suspension/brake clearance.

Example decoded

Width7.5″ J
Diameter17″
offset40 mm
Bolt pattern5×112
Centre bore66.6 mm

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Last reviewed: 2026-06-28
What changed
  • Reviewed deterministic geometry, load/speed references, sitemap inclusion and localized page shell.