Hi, I have a 2010 F1 50 with a six already in four-wheel-drive 4.6 L, my truck has had three torque converter's and finally the last one went out due to torque converter shutter. After a fresh rebuild and torque converter my torque converter was shuttering within 15 minutes of putting it back together. I noticed that my torque converter lock up valve was a little sticky so at that point I replaced my valve body, noticing the new valve body had for loose bolts and was missing for bolts I questioned its integrity, but really had no choice so I threw it in. Now in first gear the truck lurches everyone's in a while and then mid-first upon acceleration only at neutrals out about halfway through the RPMs, never had this problem with the old valve body. The torque converter still shutters but it's about 80% less than it did before. Any ideas on what you guys think it could be exactly ? If I manually put it in first in shifts just fine drives like Normal. Thanks