RALEIGH, N.C. — Inspections of big rigs on interstates and highways across the state are happening less statewide, a WRAL investigation concludes.

Over a two-year period, WRAL has learned that the hours weigh stations were open dropped by 13,000. From 2001 to 2004, 4 million fewer trucks were weighed

In that same period, the amount of fines issued dropped by $5 million.

Lt. Everett Clendenin of the North Carolina Highway Patrol said one reason for the drastic drops is manpower.

Since Motor Carrier Enforcement became part of the Department of Crime Control and Public Safety in 2003, not one of the 59 vacant officer positions has been filled.

Clendenin said it is a recruitment problem. During the merge, standards for motor carrier enforcement officers were raised.

"When applicants see there is a trooper position and a motor carrier enforcement position open -- they have to go through the same training with standards, so they are going to go to the trooper position, because it pays significantly more money," Clendenin said.

Lawmakers propose raising the salary of motor carrier officers, who make $5,000 less than high patrol troopers.

The Highway Patrol is working to fix the problem. Now, recruits are told they may be assigned as a motor carrier enforcement officer or a trooper.

Crashes involving 18-wheelers have not increased with fewer inspections, but many who drive the vehicles believe increased inspections do prevent accidents.

"It's a major safety issue," truck driver Jeff Faircloth said.

The Highway Patrol also said trucks are not being inspected as often because a new law allows them to carry more weight. It also said that because general traffic is increasing, it is increasing the demand on the patrol.