Brace yourself -- this is going to hurt.

Workers can expect an average pay raise of about 3.7 percent his year, but because of sky-high gasoline prices, they'll pour all but a smidgen of that extra cash down the gas tank commuting to work according to an analysis by Salary.com.

Calculating the toll of higher gas prices in 88 cities nationwide, the Needham, Mass., compensation software and data firm found that workers making the average annual salary of just above $40,000 last month were spending 3.3 percent of their paychecks gassing up for work.

The costliest city was Brownsville, Texas, where drivers burned through 4.6 percent of their pay on gas. Motorists there get clipped by some of the highest pump prices in the country coupled with above average commute times.

Rochester, N.Y., ranked second highest at 4.5 percent, followed by Honolulu and Riverside, Calif., both at 4.4 percent, and Albany, N.Y., at 4.3 percent.

Pittsburgh ranked 29th most expensive, with motorists spending 3.4 percent of their salary at the pump.

The cheapest city was Santa Ana, Calif., where drivers spent 2 percent of their pay getting to and from work.

More details in tomorrow's Pittsburgh Post-Gazette.