Route planning help

[garmp]

Our upcoming first trip to the badlands is wrought with concerns. Help!

How do I find which roads I can drive with my 26' RV, tunnels, turns & narrow roads etc? Is there a site, app or such that can help?
We want to go from Sylvan Lake Campground in Custer SP to Spearfish via Mt. Rushmore and I noticed there are tunnels hair pin turns & very narrow roads (google street view) that make me very nervous. Some tunnels are marked with height limits, some are not. How do I gather this info? I don't want to turn around on a one lane road and retrace a half days drive.
Thanks

[gtnsmlr]

South Dakota DOT will have all the info you need.

[Ivylog]

The CG app RV Parky shows low clearances. Stay off of 16A.

[garmp]

I just tried RV Trip Wizard and it seems to be the best alternative I've found. Seems cumbersome, but there again I just started to learn it. I will continue to search. Wish google maps had parameters you could enter for the best route.

thanks all

[MarkTwain]

Route trip planning----- I use the Garmin Diesel for trip planning.

[agesilaus]

Use RV Trip Wizard or an advanced RV GPS like the Garmin RV890. They will route you via a safe path for your RV. Or stick to Interstates.