I have bought two cars with them over an 8 yr span. I bought my girl in 2014. Things may have changed. I never had too wait long. I have only dealt with local people. I don't recall, but I bet I called their local San Jose office. Sorry, but I don't have a number in my contacts. But I found this number on my account site:
The other number they list is an 800.
Their service has been outstanding in every way. I got approved for a 75K (I think) loan in about 4 minutes while on the phone. Getting the funds to Tesla was a little tricky (It was earlier on in Tesla time...) and they were right on top of it. I paid the rest in cash. About 55K. Tesla was easy. TCU was easy. My first loan for a much cheaper car was just as simple 8 years earlier. My credit score was off the charts, which I think helps make it fast. I have since paid it all off. It was a great cash flow loan for me.
Hope this helps. Rates are rising fast due to Trump, so act fast. The 10-yr T-Bill is up 50% in a week! I'm not sure I am remembering right, But I think TCU uses LIBOR, which i am not following right now. Good luck!