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.

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 (only one left!).

 

I've seen this truck in person and these guys really know their stuff. If your wondering where to send your harness or need one call Speartech.

 

Always on the leading edge, way to go John! Another success story!

I know I couldn't be happier with my LS7 harness from you

 

Now this is great news for the LSx Conversion Family!

 

Nice!

 

I want one so bad in my S10 now. Ditch the LS1/4l60e....in with LS2/6l80e ohh yeah. Now I know what to save for!

 

I still have to order my DBW pedal from you guys for when I finally start working on my harness. I am also using the E38 for my Ly6 swap in my 96 Impala. Do I use the 05 Vette pedal? Would I also need to use my Lt1 computer to run any of my stock accessories?

 

Nice work! What are your plans for the original 4.8L/4L60e take out? I've got a father looking for an engine package for a T-bucket.

Dustin

 

Any idea as to what the cost of a swap would be with your wiring harness?

 

Yes, the 05 Vette pedal will work for that. I think the LT1 computer will go away completely.

 

Dustin,

I'm not sure yet what I'll do with the 4.8. I haven't decided if we will leave the truck the way it is, or put the 4.8/4L60E back in it. It's a lot of money sitting in it. The powertrain is worth more than the whole truck!!

 

John, that is an awesome test bed you have there! I truly envy you!!!!

 

Thanks. BTW are you guys still selling the idler pulley relocation bracket that is used when switching from the truck intake to the car? The L92 truck intake is to tall so I will be selling it and buying a L76.

 

+111111

 

Looks like it might be a good combo for my Silverado SS.

 

Yes. We have been out of stock but should have more in by the end of the week.

 

Awesome implant power plant,my cream dream for a 00-02 SWB 4x4.I found a Escalade engine trans combo here in the pacific NW 13K$$$$ .Will have to take a different approch when the time comes.

 

so is there a pricing for the 6l80 and 6l90 swap yet?

 

Oh John,

email me at work regarding getting this into the new products section. this 6L80/90 deal is going to be VERY popular

 

Yes. We have the complete engine/trans harness, programmed computer, and ETC pedal assembly for $1695.