6 Speed Upgrade?

[l008com]

My truck has a lot of miles, and while its currently running great, it won't last forever. My amateur thinking is that the transmission is probably the most likely big item to fail. They take a lot of abuse over the years. And mine seems to be making more and more odd noises as time goes on.

This is all HYPOTHETICAL but lets say it did fail, can you swap a 6 speed automatic into these trucks? 6L80 for example?

There's that famous video of someone with a 5.3 SWB LT (like me) where he swapped in a 6 speed manual. It looks amazing, but the computers freak out and it has eternal error lights on the dash.

Is it the same with the 6 automatic? Or can you grab computer module(s) from a doner truck too and really turn it into a seamless swap? Seamless meaning as seamless as swapping in another 4 speed would be.

I've often thought the transmission (a 4 speed) is one of the weakest points in this truck. Not weakest as in point of failure, but weakest as in a design choice that's not ideal. I know this truck was built a very long time ago and 6 speed autos probably didn't exist back then. But they sure do now.

If the swap is plausible, that might be something to keep in mind as a backup plan if my truck ever needs a new transmission.

 

[TollKeeper]

Simple answer is no... It likely could be done with a lot of work.. The issue is finding a GMT360 that has a 6L80 to copy the BIN file.. And they dont exist as far as I know.

I dont think you could copy a BIN file from a GMT800, as all the engine parameters are different.

It can be done if you go the route of a Stand Alone TCM.. But there are costs involved.

6l80e Transmission swap

In the past the ideas of swapping the 4L65e to the 6L80e were rightfully met with resounding No’s, and don’t try. At recently as 6-7 years ago this swap was a $7,500-$10,000 endeavor. From what I’m seeing that’s changed dramatically in recent years. Swaps from $2,000-$4,000 seems very...

hummer4x4offroad.com

 

[Mooseman]

I have to agree, not very likely. The ECM, TCM and BCM have to be able to talk to each other. And the TCM is built into the 6L80. The ECM will just go "huh?" as this generation has never had the 6L80. They probably don't even speak the same language.

And then there's the mechanical aspects. Shifter linkage would be a PITA, the transfer case has to mate to the tranny if it's the same bolt pattern and splines, the rear drive shaft would need to be shortened and the front lengthened. Heck, the speedo probably wouldn't work neither. May not even fit physically in the tunnel.

I think it's too much trouble for any of the small gains you might get.