Speartech

iTrader: (14)

I decided we needed to get the new 6L80/6L90 series of transmission up and running in a swap project to get all of the electronics and programming worked out.

We are getting a lot of calls from people interested in this new transmission.

Here's what we did:

I wanted to start with something as easy as possible for the swap since the goal was to get it up and running quickly in order to work out any electronics/wiring/programming issues so that people will be able to successfully use this setup in their projects.

I found this 2001 4.8/4L60E 2WD Silverado close by so I snatched it up for the project. It just happened to be in my color of choice, and it’s in pretty good shape with 135,000 miles on it.




The first step was to get the 4.8 engine and trans out.



For the new engine/trans I used a new LS2 Corvette crate engine (Part #19156261)

Along with a new 6L80 transmission.

I decided to substitute the truck style harmonic balancer so that I could retain the original truck accessories and brackets. That way I wouldn't need any custom power steering hoses or A/C lines made.

We then installed the LS2/6L80 as one assembly.





Because I retained the truck accessories I also had to take off the Vette LS2 intake manifold and substitute the LS2 truck intake manifold.





The 6L80/6L90 transmission uses the same style rear mount, but it sits back just a little further so we had to modify the stock rear trans crossmember a little for proper fit.



The additional bulk of the 6L80 is mostly below the mainshaft centerline, so there is plenty of tunnel clearance for the transmission. That should be good for other vehicle swaps!
The overall length of the 6L80 transmission is actually SHORTER than the 4L60E! We had to use a longer driveshaft for this project. The 6L90 is 35mm longer than the 6L80 due to the thicker gears, etc.



With everything installed we built a custom wiring harness for the truck using the new E38 controller to run it with.



Since all of these new setups are electronic throttle, we had to fit the truck with the ETC pedal.



After programming the E38 controller, the truck fired right up. Everything worked great so I took it for drive. Wow! What a first gear this thing has! The truck came stock with a 3.73 single pull rear end, and you can literally boil the rear tire all the way down the road while it shifts thru the gears!

On a truck this new we also made a mini-harness to retain the old computer so that all of the gauges and A/C would still function properly.



With everything running so good I had to jaz up the truck a little bit.

Since the main goal was to sort out the wiring harness and programming, I stayed with the stock exhaust manifolds and Y pipe. I did add a Gibson sport cat-back exhaust system with stainless tips for a little help in the breathing department (sounds great).

Since this had been a work truck and the bed was all scratched up, I added a GM one piece bedliner and a set of Silverado SS chrome wheels with Goodyear F1 tires (P275/45-20) to upgrade the looks department.

I think the truck looks much better now!






I also had a positraction unit put in the rear for some traction capabilities.

After getting it dialed in a little bit I took it to the dragstrip for a few passes to see how it would do.

All passes were in the 13’s with a best of 13.67 at 101.


I don’t have a very good feel for truck quarter mile times but I did get a lot of compliments on the looks and performance, so 13.60’s must be pretty decent.

The truck feels really strong on the street, so considering everything (no headers, street tires, stock converter, etc.) I think the times are pretty good.

Thanks to the Speartech crew for the powertrain installation and custom wiring harness.

Thanks to RPM Transmissions for the positraction unit and installation.

Thanks to Speedcraft Prototypes for the custom length driveshaft.

We recently got a skid of brand new 6L90’s in the shop. Here's what the 2WD version looks like:

00Z71

iTrader: (2)

How much would a kit like this be?

thunder550

iTrader: (70)

I may not be understanding right.....are you running three controllers now? Original PCM for a/c and gauges, new PCM for the LS2 engine, and also a separate tranny controller? Is it possible to just run the original truck PCM and a separate tranny controller?

ZZebes

iTrader: (10)

will there be a way to use the stock unit and the Tranny???

jaegmc99

Oh I want so bad!!! Now!! Even if it does work, there probably won't be converters for a while

Speartech

iTrader: (14)

00Z71- There's really not a kit price for something like this in a late model truck. More of a feasibility study on the whole thing, and the truck was just an easy platform to do it on.

thunder550- As it turns out, the original PCM is in there performing the mighty task of operating the water temp gauge and the fuel level gauge. There was no other easy way to get those two gauges to work. The A/C is basically a stand alone system not needing any of the 3 controllers.

thunder550

iTrader: (70)

Is this necessary because of the CAN bus that the new tranny runs off of? I was hoping someone would make some kind of conversion module that would allow the older style PCM's like we have to communicate with the CAN controllers that the new trans needs.

What needed to be done to the LS2 PCM to work with the 6L80E instead of the 4 speed that the Vette's and GTO's come with?

kbracing96

iTrader: (26)

4wd???? Possible????

Speartech

iTrader: (14)

I don't see any way to do it.

John

Speartech

iTrader: (14)

Yes, it's the CAN bus that changes everything. The trans will only talk to the new 58X Gen 4 engines/controllers.

I don't see anyway to use it with a 24X engine.