do i need a transmission crossmember?

[GreenMystChevy]

Okay, I feel like a moron on this one but it happens. I was driving ht etruck the other day and when I gave it some gas at a stop light, something "broke" and it pops and shudders and whatnot. It's not drivable and I think it is the tranny. There is this knocking noise coming from the inspection plate area of my 3 speed. I wanna say that the throwout bearing went bad, I broke a piece off of the clutch, something. I really have no idea.

Now the question that I posted about, I bought my truck fairly recently and I look under there and there is nothing holding up the back of the tranny? It is just a little guy and it looks like there hasn't been a crossmember for a long time by looking at all of the crap that has built up. Do you think this is what caused whatever happened?

I'll be taking the tranny out this weekend to see what happened. No I just need to find a trailer in the Seattle area. Thanks guys.