I wonder if the 8L90E, in the C7, would be available to buy and fit in where I now have a 4L70E?

 

Available yes, fit and be able to run that's highly doubtful.

 

Why this obsession with adding all these gears and making the transmission controllers stupid complicated. The worst thing about engineers is when they over-do their job.

 

I don't think the engineers had much choice in adding the gears, really. Yes they can help with fuel economy some (which is govt demanded, and with certain driving conditions, the 4spd's get the same MPG), but the number of gears is now just a basically a pissing contest between manufacturers, everybody is trying to say they have an 8spd, 9spd, 10spd etc. It sucks for us, the enthusiasts, because this means great racing transmissions like the 4l80e are no longer produced.

And yes, at some point not too far from now, 8l90's will start to pop up for the aftermarket, but they are massive. From what I have seen when people swap the 6spd autos in, they usually need to chop the floor pans up. It would only be worse with an 8spd. They will be expensive, and from all I hear about the 6spds, they are not as strong as something like a 4l80, even if they are dubbed 6l90 (the "90" should indicate higher strength).

 

These very new transmissions are controlled by TCUs with very sophisticated software that requires complex input from many other computers. Therefore the GM TCU is not going to work in any older vehicle. I suspect a standalone 8L80/90 controller is far in the future.

Aren't the 4L60E and 4L80E still being made? GM sells "new" ones with the Connect&Cruise packages.

 

6 speed standalone controllers are just now coming out, and that trans has almost been out for 10 years. And from everything I have seen, the 8 speed is even more complicated. So.... It's going to be a while before a conversion is going to be available for the end user.

Chris

 

Its been a few months now, just wondering where something like this stand for aftermarket? Seems much more refined than the 6, supposedly stronger as well. Seems like they are set up to be "manual" with the paddles so I would think a full manual could be done

 

As Chris suggested, it is unlikely aftermarket support will be available for many years.
Sorry, but you are overlooking how complex cars have gotten in recent years. Heck, in modern cars several computers are required to turn the headlights on. It probably takes 4 computers for the paddles to connect to a trans and hundreds of not thousands of functions need to be implemented for a "manual" shift to occur. I would guess that the 8L80 has 10x the computer complexity of a 6L80.

 

srorry to bring back a zombie but to the OP, I recently contacted usShift and the Quick6 tcm can handle 6 speed trans from GM and Ford and they are working on a Update so it also can work on a 10R80.... just to let you know... I got a quote the Quick4 for my 4L80 and a Quick 6 for a 10R80 and the price is not that bad..

 

just to update this thread. You were wrong lol a handful of controllers out now.

 

I think the DCT trannys have more potential. And they are available in small delivery trucks already.. FUSO(Ford) 12 speeds...

 

Thats it, everyone install 18 wheeler transmissions in the cars. 15 speeds for everyone!!!!

 

not really you quoted a post that is 2 years old , things change what was not quite available yet then is now

 

At this point I would think that the torque converter doesn’t need to stall very much. With 6 and 8 speeds there can’t be much of an RPM drop between shifts.

 

Name 1

 

Oops forgot to quote.

 

I drive for a living, Im fully aware that ano Allison (heavy equipment) transmission is impossible to fit in...let's say an f body. BUT I would curious to see how much hp it would sap. I wouldn't be surprised to see an 800 hp motor....delivery 475rwhp through one of those trannys.

 

What would be a start is to transplant the required transmission with engine, wiring and control units from a wreck. In my experience more practical than using an aftermarket controller plus you have OE advantages.

 

Happens all the time.....