2005 1500HD swap late 6.2 or 6.0 8 speed drivetrain

[4ws f 7]

Have 05 1500HD Quadrasteer which I love! Has 6.0 with 4 speed, range when towing is just over 200 miles. So I would like to switch a late 6.2 with 8 speed drivetrain which is very expensive, or a late 6.0 VVT with 8 speed just not sure if being cheap at the point that I am changing drivetrain I should just do 6.2. My questions are has anyone done this type of change as searches have not come up with much. Have been waiting a few years for 4 wheel steer to return but seems like it never will. Thanks for any information!

[swathdiver]

Trouble with such a conversion is that the computers and wiring harnesses are completely different and do not talk to the BCM either.  You might want to beef up or stroke your 6.0 for more torque and maybe add a Gear Vendors over-drive instead.

 

What would provide a greater benefit to you, the 4-wheel steering or the higher horsepower engine with more gears?

[4ws f 7]

1 hour ago, swathdiver said:

Trouble with such a conversion is that the computers and wiring harnesses are completely different and do not talk to the BCM either.  You might want to beef up or stroke your 6.0 for more torque and maybe add a Gear Vendors over-drive instead.

 

What would provide a greater benefit to you, the 4-wheel steering or the higher horsepower engine with more gears?

My thought was if I have to I will run 2 ignition keys, and will need a complete parts truck. I do love the 4 wheel steering, but would love more power/range that a later drivetrain would give.

[davester]

It's more than just shoehorning the engine and transmission into the truck.  The ecm and tcm communicate with the bcm and ip for the truck to function, and the newer ecm/tcm needed for either the vvt 6.0 or 6.2 don't work with the older bcm & ip in your truck.

 

And the quadrasteer setup makes it that much more challenging, because it probably also depends on the ecm/tcm to determine how it works (as in, you probably get more rear steering when going really slow, vs at highway speeds).

 

And after doing all this work, assuming you manage to get all the electronics right, you probably aren't going to get much of an increase in mpg, just because it takes so much power to get to a 3+ ton brick down the road at 60+ mph.

 

If you want more range, I would suggest trying to find a larger tank to replace the factory one, or a tank in the bed and rigging up something to transfer fuel to the main tank (this isn't particularly safe, as gas more volatile than diesel, so I haven't come across in-bed gas tanks (but I also haven't looked very hard for them).

[swathdiver]

3 hours ago, 4ws f 7 said:

My thought was if I have to I will run 2 ignition keys, and will need a complete parts truck. I do love the 4 wheel steering, but would love more power/range that a later drivetrain would give.

You can ask the guys over at the Performance Trucks forum about what the conversion of yours may entail but I think you'd be better served by just going with a newer truck.

[davester]

It will be WAY simpler for you to just get the engine tuned, and maybe add a turbo or supercharger to get more power.  Trying to put in an engine/transmission from a newer truck will take much longer, and you'll have all sort of things that just don't work quite right anymore.  And diagnosing problems will be much easier, as the OBDII port for scanning the truck is connected to everything.

[davester]

Just to follow up, prior to opening the wallet for doing performance enhancements, make sure in advance that they will work with your quadra-steer system, as it's my understanding it's fairly integrated with the engine and transmission computers, and the tuners may not be aware of or experienced with how the quadrasteer interacts with the ecm/tcm.

[4ws f 7]

Thanks for info. I am a little worried about the 4ws working my self. Really have been looking at late 6.0 L96’s with the 6L90’s as they are very reasonably priced  for complete drivetrains.

[4ws f 7]

Davester thanks again for your input. Zero Gravity sells everything needed to install a 6L80 or 6L90, so I may start off with that, as hoping the .85 fifth gear will work well when I am trying to do 70 to 80 mph up hills, the 4L80 has a 1.0 3rd which screams bloody murder now. I have a 93 tune from Nelson which is 12 or so years old, would a newer tune be any better?

[davester]

IDK. Maybe your engine has the power to keep up 70mph with .85 ratio, that it doesn't have with the .75 OD ratio of the 4l80e.  If/how it works depends on, well, all kinds of stuff, from wheel size, diff ratio, weight of vehicle, what the tune does to alter the engine and transmission tables.  I wouldn't be surprised if just a tune wasn't enough to keep your truck going uphill speed in an OD gear (as in, you'll probably need something like a turbo or supercharger to give the engine enough power to maintain that gear).

 

But talk/email to a couple different tuner's and see what they say about making this happen.

Edited August 25, 2019 by davester