97 gmc yukon 5.7 to 5.3 swap

[Brokenyukon]

So i got the 350 out yesterday and I took the torque converter out of my current trans and compared it to the newer one. Only thing I noticed is the inlet hole on the newer torque converter is a touch longer than the older one. So I checked to see if it slides into my 97 4l60e. Which it does without any issue. It seats fully in and spins perfectly. But I'm wonder if i need the crank spacer for what I'm doing. All the threads I've read people say you need it when using the 5.3 with an older trans like th350 or the 700r4, but no body mentions if you need it when using an older 4l60e.

[Disney]

So i got the 350 out yesterday and I took the torque converter out of my current trans and compared it to the newer one. Only thing I noticed is the inlet hole on the newer torque converter is a touch longer than the older one. So I checked to see if it slides into my 97 4l60e. Which it does without any issue. It seats fully in and spins perfectly. But I'm wonder if i need the crank spacer for what I'm doing. All the threads I've read people say you need it when using the 5.3 with an older trans like th350 or the 700r4, but no body mentions if you need it when using an older 4l60e.

Yes, you'll still need the crank spacer.