This might be a bit late, to respond to this post, but here goes.
To get your garbage / recycling working correctly do the following:
1. Make sure your public transport works well, to ease the traffic flow.
2. Make sure to educate your sims to have them recycle more than they trash.
3. Make sure not to send your trucks to neighboring cities or to have your garbage / recycling collected by neighboring cities.
4. Make sure you have enough garbage / recycling trucks and make sure you don't run out of space, if you run out of space, it might be time to upgrade your recycling / garbage centers.
5. Make sure to have a trade center and to have enough trucks to go to the trade center, from your recycling center.
6. Make sure to have storage holds for the type of materials you recycle, at both the recycling center and trade center, ie: alloy, plastic & metal.
7. Make sure you have enough trucks at the trade center to get rid of materials.
8. Easiest way to get rid of materials is to have it sold to the market.
If you were to follow these steps, you are ensured to have a well functioning garbage system.
9. Make sure to start educating your sims early and to start both recycling & garbage collections early to ensure you don't run into trouble.
I hope this helps other people that might be struggling with this issue.