Give Trek a call. They are well versed on all aspects..especially parts for road bikes.
Bring in the bike you need the shifter for whenever you get a chance and we can show you your options. If you can't bring it in, give us a call or stop by and we'll help you out as best we can. Estimates are always free!
Sometimes it's best to take the whole bike in for them to look at. Free estimates and peace of mind knowing you didn't miss anything.
Thanks! Your answer is awaiting moderation.