Take a look at this link. Scroll down to the 3155 and 3156 Click Link
These are both T25 Wedge Base size S8 bulbs.
The 2011 owners manual Click Link
on page 43 only references the bulbs by their trade name as 3155.
I would not recommend putting a 3156 in place of a 3155 due to the difference in current draw between the two.
Here's GE's bulb chart. Look on page 11 Click Link