1985 2500 4x4, 6.0 4L80e. will a 208 TC handle it??

[Nasty-LSX]

I am finally getting around to the 4x4. She has been neglected for some time now. Been doing alot of LS swaps for everyone else. Now im taking some time for my own rides.

Long story short, I burned up the transmission in my 06 short bed single cab 5.3 4L60e silverado.
I made a 200 mile trip pulling a car trailer that weighs about 2100 LBS Empty. on the next 200 miles back with just a car shell, total weight maybe 3500 LBS is when i burned it up.

MY GOAL!! Swap a 6.0 with a BUILT 4L80E. Trans will have all the goodies.. 6.0 will have full bolt ons
with the truck intake still installed. I will have a custom grind cam for good power and TORQ!! engine should be in the power range of 400 HP or under to the rear wheels. Not building race truck. Just want a good cruiser and hauler that can pull 5000LBS easy.

I will say it has a stock GM GOODWRENCH 350 replacement engine done years ago with a turbo 400 trans.
It will pull 5500LBS with ease. The only reason I dont use this truck is because I get about 9/12 mile per gallon. Pulling is even WORSE!!

Will I have any problems running a 208? I have read the 241 TC is a upgrade from the 208 and all bolts up the same. Im just trying to build a STRONG RELIABLE truck to pull short and far distance with decent mileage. Not a off road or rock crawler.. Thanks!

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[Nasty-LSX]

I tried to find 208 HD upgrades to make it stronger but there is nothing out there. Only stock replacement parts. I dont want a 205.

 

[RoryH19]

I am finally getting around to the 4x4. She has been neglected for some time now. Been doing alot of LS swaps for everyone else. Now im taking some time for my own rides.

Long story short, I burned up the transmission in my 06 short bed single cab 5.3 4L60e silverado.
I made a 200 mile trip pulling a car trailer that weighs about 2100 LBS Empty. on the next 200 miles back with just a car shell, total weight maybe 3500 LBS is when i burned it up.

MY GOAL!! Swap a 6.0 with a BUILT 4L80E. Trans will have all the goodies.. 6.0 will have full bolt ons
with the truck intake still installed. I will have a custom grind cam for good power and TORQ!! engine should be in the power range of 400 HP or under to the rear wheels. Not building race truck. Just want a good cruiser and hauler that can pull 5000LBS easy.

I will say it has a stock GM GOODWRENCH 350 replacement engine done years ago with a turbo 400 trans.
It will pull 5500LBS with ease. The only reason I dont use this truck is because I get about 9/12 mile per gallon. Pulling is even WORSE!!

Will I have any problems running a 208? I have read the 241 TC is a upgrade from the 208 and all bolts up the same. Im just trying to build a STRONG RELIABLE truck to pull short and far distance with decent mileage. Not a off road or rock crawler.. Thanks!

You must be registered for see images attach

There is a 32 spline np208 for the 3/4 trucks. These would be run with th400s. The np241c is an upgrade and has both 27 and 32 spline count. I run a np241c for my ls swap. 6.0/4L65e/np241c
This not only is a better t-case but it will give you the digital output for the pcm to shift the trans.

 

[Nasty-LSX]

it will give you the digital output for the pcm to shift the trans.

I forgot about that!! What Ls harness did you use? I have been using PSI CONVERSIONS with great results. Have Never done a 4x4 before so not sure what all would be different. Thanks

 

[RoryH19]

I forgot about that!! What Ls harness did you use? I have been using PSI CONVERSIONS with great results. Have Never done a 4x4 before so not sure what all would be different. Thanks

I modified the stock one and included additional relays for electric fans.
It's DBW and I have everything working including cruise control.

Main difference is the vss is on the t-case and you need to add a simple switch when going to 4 low.
Also if you go from np208 to np241 use the cross member from the 241.

 

[Rusty Nail]

Dude, I really like your truck-what a great lookin ride!

I'm surprised buying transmissions is easier than buying more gas because it's cheap here.

 

[roundhouse]

I do a lot of towing , bobcats and mini excavators with a 2017 2500 4x4 chevy crew cab and I always use the manual shift buttons to keep it in 4th when I’m towing

If you let it , it will shift to 6th and melt the trans .
Runs about 3300 rpm at 65 mph
Sucks down the gas but cheaper than a new trans

 

[Nasty-LSX]

ROUNDHOUSE I learned my lesson. It was my fault!

 

[Camar068]

Sounds like you have a 32 spline NP208 since it's bolted to a TH400 unless the trans has been downgraded to 27 spline. From where your sitting at now, you need to figure out how your going to get your VSS signal IF you don't get an NP241 with VSS signal out. Come up with your choice of VSS option and price for that, then compare to the price of an NP241 in your area.

I think a 32 spline NP208 will work fine with that HP after reading a few posts elsewhere on the web.

 

[dragstews]

On the replacement trans, might be best to find a 4L85E instead of the 4L80 ... Built much stronger ...

 

[Rusty Nail]

Voted yes.