1985 k1500 6.0 swap

[bls77red]

hi currently researching options on a complete motor drop out. I would like to use a low miles 6.0 and use a 4l80e. or the newer i90 six speed auto trans. my questions are would these transmissions bolt to my transfer case? I currently have 350 with 700r4 . any input or some links would be appreciated.. I would like to start my project soon. thanks

 

[MadOgre]

hi currently researching options on a complete motor drop out. I would like to use a low miles 6.0 and use a 4l80e. or the newer i90 six speed auto trans. my questions are would these transmissions bolt to my transfer case? I currently have 350 with 700r4 . any input or some links would be appreciated.. I would like to start my project soon. thanks

The 4L80 will bolt to any transfer case and adapter from a TH400 as they use 32 spline input gears and 6 bolt adapters but it will not bolt to one from a 700r4 as they use 27 splines and 4 bolt adapters. You can how ever swap out input gears but this requires complete disassembly of the transfer case.

241 transfer cases are better than 208s and a little easier to disassemble. These transfer cases input gears can also be swapped to match your needs

 

[bls77red]

The 4L80 will bolt to any transfer case and adapter from a TH400 as they use 32 spline input gears and 6 bolt adapters but it will not bolt to one from a 700r4 as they use 27 splines and 4 bolt adapters. You can how ever swap out input gears but this requires complete disassembly of the transfer case.

241 transfer cases are better than 208s and a little easier to disassemble. These transfer cases input gears can also be swapped to match your needs

Thanks ..not sure what transfer case I have .its a 85 1/2 ton. Would the 4l60e be a better fit right off?

 

[MadOgre]

You have a 208

If your gonna go to all the trouble of putting an Electronic transmission in it, I would definitely go 4L80. It is a nice heavy duty transmission based off the TH400 but with an overdrive utilizing a locking torque converter.

The 4l60 is not nearly as reliable or as strong as the 4L80

Either way your gonna need a transmission controller.

You can even mate a 205 to the 4L80 with a bit of work mind you.

The 208/241 can be mated to the 4L80 using stock adapters as far as I know. The same would be true for the 4L60 as well.

 

[bls77red]

The 4L80 will bolt to any transfer case and adapter from a TH400 as they use 32 spline input gears and 6 bolt adapters but it will not bolt to one from a 700r4 as they use 27 splines and 4 bolt adapters. You can how ever swap out input gears but this requires complete disassembly of the transfer case.

241 transfer cases are better than 208s and a little easier to disassemble. These transfer cases input gears can also be swapped to match your needs

Any fitment ideas on the 6l90 transmission to the transfercase?

 

[MadOgre]

Any fitment ideas on the 6l90 transmission to the transfercase?

haven't but I will see what I can find

 

[bls77red]

haven't but I will see what I can fOTE]

Thanks . I found a 2010 6.0 with the trans.it was out of a hd truck. I.couldnt find much out there on this transmission.other than specs. Not sure what bolt number the hub is

 

[350runner]

Man I'd really like to see that trans be put to use. I plan on using that same setup for two vehicles.

Sent from the dust in front of you!

 

[MadOgre]

haven't but I will see what I can fOTE]

Thanks . I found a 2010 6.0 with the trans.it was out of a hd truck. I.couldnt find much out there on this transmission.other than specs. Not sure what bolt number the hub is

So you have a 6L90 ? That came with your 6.0 ?

 

[bls77red]

haven't but I will see what I can find[/Q60OTE]

Scrapped the idea of the 6l90. Thinking of just doing a 5.3 and the 4l60. Will the output shaft of the trans need changed to work with the 208 transfer case? And what would need done to make the speedometer work?

 

[firebane]

You have a 208

If your gonna go to all the trouble of putting an Electronic transmission in it, I would definitely go 4L80. It is a nice heavy duty transmission based off the TH400 but with an overdrive utilizing a locking torque converter.

The 4l60 is not nearly as reliable or as strong as the 4L80

Either way your gonna need a transmission controller.

You can even mate a 205 to the 4L80 with a bit of work mind you.

The 208/241 can be mated to the 4L80 using stock adapters as far as I know. The same would be true for the 4L60 as well.

Sun Shell go

 

[MadOgre]

haven't but I will see what I can find[/Q60OTE]

Scrapped the idea of the 6l90. Thinking of just doing a 5.3 and the 4l60. Will the output shaft of the trans need changed to work with the 208 transfer case? And what would need done to make the speedometer work?

your current 208 will work only with a 4L80. So to make it work with a 4L60 you need to change the input gear to a 27 spline. You will also need an adapter to bolt it to your transmission. But you need one any ways as the sm465 adapter can not be used on automatic transmissions

 

[MadOgre]

The easier and probably cheaper way is to go find one at your local wreckers and get the cross member, adapter and transfer case from a passenger side drop 700r4 or 4L60e

You probably can find a 241 with adapter and cross member for $100 or less

 

[bls77red]

Im in the process of getting the 5.3 l33 vortec. and whatever trans that will go together the best.i will get ecm for trans and motor to work . my current original 700r4 has a lot of miles on. I have the np208 transfer case that I want to retain. from what I have gathered is that the 4l80 has the correct number of output splines to mate to the np208 input..correct? and there will be a adapter to mount trans which is a 6 bolt to the 208 case which is a 4 .. correct? im new to 4x4 transfer case.sorry for what might seem silly questions.i just want to get the right parts first .thanks for any advice

 

[MadOgre]

Ooops I thought for some reason you had a sm465. Oh well yes the 4L60e uses the exact same everything from the 700r4. Yes you can put a 4L60 behind your 5.3 and then just bolt your current transfer case, adapter and cross member behind it