Originally Posted by banorcal
well, like you said going all out. I was also planning of replacing the tranny with an Allison transmission if I went with the 6bt. It's a blueprint i have that wont get done for a long time ha
A 12v weights in at 975lbs and a 24v weighs 1,150lbs. The 4BT weights 782. Adjustments will have to be made to the front end of the 1/2 ton truck to hold a 6BT and maybe even the 4BT. The weight of these motors will be the issue. Your front suspension wont last very long witht that kind of weight. Remember that the 4BT weights around double of what your 4.6L would weigh.
The 4BT would be less powerful than your original 4.6L as far as stock hp and torque goes.