Moving cache to SD Card? Is it possible?
it is possible, but you will need to get a root. 
FolderMount allows to transfer not the apps but their cache. This program requires root access. If you don’t know what root is then go here and here to read about how to gain root access.

Cache transfer is performed in a few simple steps:

Open FolderMount and press “+” in the top right corner.
Name an app that has leftover cache in the internal memory.
Press “Source” and indicate the folder with the app’s cache. It is located in Android/obb/the folder with the app’s name.
Press “Destination” to choose a folder on the SD card for the transfer.
After every field is filled out, press the check mark in the top right corner and select the “pin” next to the Name field.


Read here http://droidguides.com/applications-to-sd/