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KY Regulations

Trucking Regulations in Kentucky

Complete guide to weight limits, speed limits, permits, chain laws, and special rules for commercial truck drivers operating in Kentucky.

Max Gross Weight

80,000 lbs (extended weight permits on coal haul roads)

Truck Speed Limit

70 mph (same as cars)

Diesel Tax

$0.246 per gallon diesel + $0.02 supplemental + federal

Weight & Size Limits in Kentucky

MeasurementLimit
Max Gross Vehicle Weight80,000 lbs (extended weight permits on coal haul roads)
Max Axle Weight20,000 lbs single axle, 34,000 lbs tandem
Max Trailer Length53 ft trailer, 65 ft overall
Max Width102 inches
Max Height13'6"

Speed Limits for Trucks in Kentucky

Rural Interstate

70 mph

Urban Interstate

55 mph

Truck-Specific

70 mph (same as cars)

Fuel Tax & Tolls in Kentucky

Diesel Fuel Tax

$0.246 per gallon diesel + $0.02 supplemental + federal

Toll Roads & Bridges

No state toll roads. Ohio River bridges (Louisville area) have tolls: RiverLink system, ~$12 for trucks. No tolling on other routes.

Chain Laws & Weather Requirements

No chain law. Eastern Kentucky mountain roads can have winter weather requiring caution.

Oversize & Overweight Permits

Kentucky Transportation Cabinet. Coal haul roads have special weight permits. Online permitting available.

Port of Entry & Weigh Stations

Weigh stations on I-75, I-65, I-64, and I-71. Kentucky also enforces at Ohio River bridge approaches.

Special Rules for Kentucky

1
Kentucky-Unique Unit (KYU) number required for all trucks operating in the state
2
Coal haul roads have extended weight limits with special permits
3
Ohio River bridge tolls in Louisville area ($12 for trucks via RiverLink)
4
Eastern Kentucky mountain roads have steep grades and tight curves

Hazmat Route Restrictions

Hazmat restricted through downtown Louisville and Lexington. Designated coal haul routes have specific hazmat protocols. Ohio River bridge hazmat restrictions apply to some crossings.

Rest Area & Parking Rules

Rest areas allow parking up to 4 hours. Kentucky Welcome Centers have truck parking. No state anti-idling law.

DOT Inspection Frequency

High. Kentucky Vehicle Enforcement is aggressive, particularly on I-75 and I-65 corridors and coal haul routes in eastern Kentucky.

Looking for Trucking Jobs in Kentucky?

Browse CDL driver positions and connect with carriers operating in Kentucky.

Frequently Asked Questions About Kentucky Trucking Regulations

What is the KYU number required in Kentucky?

Kentucky requires all motor carriers operating in the state to have a Kentucky-Unique (KYU) number, which is separate from the USDOT number. The KYU number is used for weight distance tax collection. It must be displayed on the vehicle and obtained through the Kentucky Transportation Cabinet.

What are the Ohio River bridge tolls near Louisville?

The three Ohio River bridges in the Louisville area use the RiverLink electronic tolling system. Trucks pay approximately $12 per crossing. There is no cash option; tolls are collected electronically via transponder or by mailing a bill to the registered vehicle owner.

What are the special coal haul regulations?

Kentucky has special weight permits for coal haul roads in eastern Kentucky, allowing weights above the standard 80,000 lb limit. These permits are specific to designated coal haul routes and come with specific conditions. Coal haulers pay an additional road tax.

What is the truck speed limit in Kentucky?

Kentucky allows 70 mph for trucks on rural interstates, matching passenger vehicles. The Mountain Parkway and other eastern Kentucky routes have lower posted limits. Urban areas are 55 mph. Eastern Kentucky mountain roads often have advisory speeds for trucks well below posted limits.

How strict is truck enforcement in Kentucky?

Kentucky Vehicle Enforcement is known as one of the more aggressive enforcement agencies in the region. They focus heavily on weight compliance (I-75, I-65), coal haul compliance in eastern Kentucky, and KYU number verification. Out-of-service rates are above the national average.