today I pulled into a parking spot and felt something weird. When I got back in and backed out, my x5 started shuddering. It's shuddering at low speeds and idle. I googled it and all of those are saying that it's either my transmission fluid or my transfer case. Could yall help me to figure out what could be wrong? I have just over 120,000 miles and it's a 2007 4.8i.