I am building a 6.0 motor, and I want use the crank outta the 6.0. What i have heard is the early year 6.0's wont work with the 4l60e tranny, the flange on the back of the crank is thicker. But on the newer 6.0's the crank with work with 4l60e. I dont know what year my motor came out of, it was a complete block with alum 317 heads, so I assume its is a newer style block, is there anyway I can check to see if the crank is the correct one before I bolt everything together? <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />

 

I have heard of this same issue but I am not sure how to tell which crank it is. I do remeber that you could have the crank turned down and it would work.If I had a way to accurately messure the cranks I have a 6.0l and an LS1 crank here at the house but I dont think my tape measure would be to accurate. <img border="0" title="" alt="[Embarrassed]" src="gr_emb.gif" />

 

If you could see a standard LS1 crank in the block and the 99-00 6 liter crank in the block, you would visually be able to tell. The 6L is at least 1/4" longer in the back. If you mounted a flexplate / converter to it, it would wedge the converter into a 4L60.

If it is a stock longblock with aluminum heads, you are safe.