Snapped input shaft on Huges built 4l60e on only 10 pounds of boost! Doing 4l80e swap using 04 low mile unit. What mods should I do? I have an 01 C3 6.0 76mm turbo. I would like to run as much boost possible on 93 and water injection. I don't know what that is with 9 to 1 forgings. I can't find a long AWD dyno in my area, Atlanta, for proper tuning. I have a new PI 3000 multi-disc converter. I have a stock or maybe ls6 cam. 80% street/ATL hwy-20% strip.

 

Throw a HD2 shift kit in it and go ride..

 

What he said^^^

 

Because the input and output shafts seem to get confused by many I'm going to ask. Did you break the shaft going into the converter or into the transfer case? I refer to the input as the one that goes into the converter. If you broke this shaft I'm going to question if you had the TCC set up to be applied under wot or during shifts. These are the two things that I see often break this shaft. If you plan on doing this with a 4l80E I'm going to recommend that you install a billet input shaft. I have seen a few of these break as well from doing what I stated above. Also make sure you keep the shifter in the D3 position during spirited driver mode! This will bring the over run clutches on in this range and help the OD roller survive. HTH Vince

 

Yes the input shaft to converter. In D, making 10# boost, I floored it, trans kicked down, and loud kapow. I don't want this to happen with 4l80e, so I got pro HD2 kit. But my trans guy, who only does GM builds- mostly race, refuses to use transgo kit. He only uses superior brand kit. Anyone know this kit? I want to turn up boost, on race gas, and not kill trans. Other than strong input shaft, gear selector in D3, HD2 or superior kit, is there anything else I need?

 

This is what I'm planning on doing. I hope it's enough. Any particular transmission fluid you guys recommend?

 

Dex 3 is what I was told to run. I just go with the cheap stuff. As long as it's not overheated it will be fine.