running like crap

340mopar said
When you took the rearend out, did you possibly bump or run into the fuel line by the tank?

Chuck

I agree with chuck. Gear will not hurt your drivabily like that. It does sound like you engine is starving for fuel. Check your fuel lines even fuel filter. You mau have jarred some crap in the gas tank up. Check fuel pressure to make sure it is nto dropping to zero.