Hi there. Let me explain a few basics about jungle in TT.
First of all, jungle in TT is harder than in summoner rift. Minions do not heal you up when killed and since the "health potion nerf" (several month ago, potions healed 50 more hp, that means 250 more hp if you carry 5 pots) jungling have becomed rare.
In order to jungle you need to use really good junglers and also be lvl 30 in order to have decent runes and masteries (this is really important).
Always take smite. Doing Dragon in TT is extremely important. In my opinion 1 Dragon = 5 Kills (since it grants you tons of gold and exp, and possibly the best buff in the game).
Routing: small camps first until you reach lvl 4 or 5. You can do green or grey buff if you are shaco only. There are lots of possible routes. One of the best tactics in my opinion is starting at their top small camp (wolves or small golems), then do yours and head mid for wraiths and red (always bring help, leash works here too!). In ranked, if your team has a strong lvl 1 you can invade their mid/bot camp and steal their wraiths, then do yours and head top camps (this will force you to gank top in most of the cases. Thats why I dont use this route, because I like ending up with red and having the possibility to gank either bot or top).
If you dont have smite on your team, ALWAYS invade. You have 1 summoner spell extra for lvl 1 fight. That could mean 1 exhaust, ignite or heal extra for your team, and that means a lot.
You can switch (bot prefered) lane and go jungling everytime smite is ready. This works good and helps ganks a lot. Nunu and Cho gath are good doing this. Even if you are not the jungler in your team, you can switch going jungle if you have a decent burst (like mordekaiser, he can leave lane and do small wraith camps in 2~4 secs!).
Always bring pink wards to red buff zone and dragon. Both are crucial paths and will give almost all de vision you need in order to prevent almost ANY gank.
Oh! I forgot to mention that WRIGGLES LANTERN IS A MUST in TT. Your team will ALWAYS need this item. If your team does not have a skill that can easly nuke dragon, try to get 2 of this item. It gives you everything you need in TT and its cheap.
I will list some junglers that do well in 3v3, some of then can solo jungle, others need laning.
-Lee Sin (he is possibly the most versatile champion for TT. Pick it or ban it!)
-Shaco (great ganker, can solo dragon easly, high movility... same as Lee in my opinion)
Most champions can do jungling, but if you are looking some competitive advantage these are the most efficient ones. Im almost sure that i forgot to mention 1 or 2, and I will be glad if you add them to this list
Wish you luck in TT. Cya
PS: sry for my bad english
PS2: nunu will be buffed on next patch, try it! (procs good with olaf)