OLYMPIA, Wash. - A potential fix to Sound Transit 3’s car tab sticker-shock is causing surprise of its own.

“It’s definitely a different kind of sticker-shock,” said State Rep. Judy Clibborn, D-Mercer Island.

Clibborn chairs the House Transportation Committee and hoped to find a way to lower ST3’s car tab fees, which have surprised car owners.

Sound Transit will a use a 1999 formula to calculate a car’s value until bonds are retired in 2028.

Lawmakers suggested using an updated formula and asked Sound Transit what impact that would have to the measure backed by voters last November.

A Sound Transit memo, written to lobbyists in Olympia, estimated the hit to projects would be “more than $6 billion,” nearly 11 percent of ST3’s budget.

Clibborn said learning of the $6 billion figure has made her rethink changing the car valuation system.

“It may not get fixed,” said Clibborn. “I always have to remind everybody they did vote for it, so it’s kind of difficult for us to come in and remove that.”

Clibborn said she is trying to get low-income drivers to receive rebates if they need help paying for new car tab fees.

State Senator Dino Rossi said he thinks the $6 billion figure is an overestimate. He is still pushing for reform, even if it means projects don’t get completed.

“Sound Transit’s never fulfilled a promise they’ve made so far, so why should they start now?” asked Rossi.