Swap in 4L80E in C/K 1500?

1999 Tahoe 4x4 · October 24, 2006

Is there an easy way or possibility to swap plug & connect the stornger 4L80E in place of the 4L60E of a 1/2ton truck. I'm wondering if all connections are the same or IF MINOR, what modifications have to be made.

As far as I saw the vehicle speed sensor is on a different location. What else needs to be changed. Are there any kits available? (e.g. Advance Adaptor etc.)

Does anybody has any experience with this?

95Sierra2500 · October 25, 2006

As far as bolting it in, you should be able to (I think). As for wiring...I'm not sure.

thecraft · October 25, 2006

It can be done, but I think the modifications will be a little more than just minor.

I found a webpage through a Google search that explains what needs to be done. I haven't read the whole thing, but it looks intresting: http://www.neufamily.org/4l80e/4l80swap.html

BTW, if your engine is mostly stock and doesn't tow much, it might just be better to get a tranny shop to rebuild and beef up your existing 4L60E. Probably much cheaper and easier that way. The 4L80E would be overkill for a daily driver...

99Silver6.0 · October 25, 2006

Its not an easy swap. It takes a good amount of parts. Im gonna assume this will live behind an LS motor!?!? Speed-Engineering makes every part you would need to perform that task. Youll of course need the 80E, converter, wire harness, tranny lines, new x-member, shorter drive shaft, flexplate, flexplate spacer, trans mount and most important an updated PCM that has the ability to control a 4L80E!

Important note!!! If you have a stock motor or near stock. This swap IMO is a bad idea. The 4L80 has obscenely low first and second gear. Most guys that are running FI, forced induction, love that for traction reasons. But an NA motor running a 4L80 will be pretty doggy. Takes a good amount of power to turn an 80. Plus, its a heavy ass tranny!

1999 Tahoe 4x4 · October 25, 2006

Thank you for your replies. Unfortunately you guys exactly confirmed my worries. So I guess I'll just see how much longer my existing 4L60 will last and then have it rebuilt stronger.