FatfreeGTO

Hey everyone I have searched and I just can't find what I'm looking for so I have to ask here.

I bought an 08 LY6 from a 2500 silverado that had a 6l90e. I picked up an 09 4l80e from an express van. Do I need a different flexplate or a spacer to put the 4l80e behind my engine?

I have the truck harness with the 6l90e wires... Do I need a different harness or can I modify this one I have to work with the 4l80e? Is there an adapter plug for this or do I need to run new wires? I did pick up a t42 tcm so I need to wire that up also.

And lastly the 4l80e has the full spline output shaft about 5" of splines. Can I use my slip yoke from my th400 that is fully splined? It slips on I just don't understand the o-ring issue others have talked about.

If you can help thanks!!

bhop42

iTrader: (2)

Not sure about the other stuff but your flexplate will work.

Circle-D

iTrader: (21)

I am not sure about the flexplate, but the 6L90s we have built use the LS bolt pattern. So the 4L80 will not bolt up to it. You might need to swap to the GM# 12621399, which is the 6.0 4L80. The kit comes with the spacer and new bolts. If you want to step up to an SFI one, we have a really nice choice. It also depends on which converter you are going with. Let me know...

Chris

bhop42

iTrader: (2)

I stand corrected then. I thought the 4l80's used a standard Ls flexplate which is what I use on my 6l90e.

FatfreeGTO

Thanks for the flexplate info!

Circle-D

iTrader: (21)

Your welcome...

Chris