Cannondaleriders

have been to doing a lot of dune riding and i am finding the ohlins suspension to stiff. i have lubed my a-arms but it still is pretty stiff for the dunes. the back can be adjusted a number of ways but the front can only be adjusted for preload. will changing the shock oil to a different grad e help?????? any suggestions would be appreciated

thanks dan

It would help but changing the valving and springs is better!