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Axle Balance Tandem hole rules by state Illinois
Illinois tandem hole rules: 45 ft 6 in kingpin to rear axle
For a 53 ft van, reefer or flatbed with a sliding tandem · Checked October 2026
Limit Illinois limits the distance from the kingpin to the rearmost axle to 45 ft 6 in.
Where it applies: Trailers over 48 ft on Class I and II highways. Lower limit (42 ft 6 in) on Class III and other non-designated roads. Livestock trailers exempt.
Class III and local roads: 42 ft 6 in (Equipment World).
How to read it
Measure from the kingpin to the center of the last axle on the trailer. On a tandem, that is usually about 2 ft farther back than the tandem center, so this rule is tighter than a center-measured rule of the same number.
Source
625 ILCS 5/15-107. Rules checked October 2026. Laws and enforcement change, so confirm with the state before you rely on this.
Set it in the app
In Axle Balance, open State rules and tap Illinois, or plan a route through it. Pro shows which tandem holes are legal for your trailer and warns you before a slide would put you over a state's limit. New to sliding? Read how to slide tandems.
Other states
Know which way to slide before you get back on the scale. Axle Balance is a free calculator made by a trucker. Enter your scale ticket and it tells you which way to slide your tandems and how many holes, plus your fifth wheel. Works offline in the cab.
Open the free calculatorEstimates and general information only, not legal advice. Laws change and enforcement varies. Always confirm on a certified scale and with the state before you rely on it. See the Terms of Use.