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4l80E NP205

SKUBASTEVE1010

SKUBASTEVE1010

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I have a 72 blazer 4X4. I already have a 6.0 installed with a 700R4. I have a 4L80E in the shop being rebuilt. I will be sending the NP205 to the same guy to rebuild. The 6.0 already has a complete wiring harness. The truck is up and running. What wiring harness do you guys recommend for the 4l80E and are there any prefabbed mounting brackets out there for this set up? Thank you in advance.
 
Are yiu running a stock ecu? I would think you'd have the 4l80e as part of the 6.0 harness if you know you were going that way.
If you plan on running a stand alone trans controller, it should come with a harness.
 
I bought a stand alone 6.0 harness and I am using the stock ECU. My original plan was to stick with the 700R4. But of course I changed my mind.
What trans controller do you recommend?
Thank you.
 
SKUBASTEVE1010 said:
I have a 72 blazer 4X4. I already have a 6.0 installed with a 700R4. I have a 4L80E in the shop being rebuilt. I will be sending the NP205 to the same guy to rebuild. The 6.0 already has a complete wiring harness. The truck is up and running. What wiring harness do you guys recommend for the 4l80E and are there any prefabbed mounting brackets out there for this set up? Thank you in advance.
Click to expand...
When you say “mounting brackets” are you speaking of ECU and wiring components or the mounting of the 4L80E/205 combo to the chassis ?
 
Gotcha,
The easiest way is to use the one year only ( ‘91 K30 or I should say V3500 to be absolutely correct ) adapter.
I’m assuming that your NP 205 is an ‘85~’91 round pattern long 32-spline input case ?

You can also use an ‘85~’91 1/2 or 3/4 Ton short mount crossmember and just drill through holes in the frame in the correct locations just as GM did originally.

You can achieve all this with OEM parts and will look somewhat factory appearing.
 
SKUBASTEVE1010 said:
Thank you! I am in the beginning phases on trying to figure this out. I have limited knowledge.
Click to expand...
The wiring harness for the 6.0 may or may not have the connections added to it to control the transmission. You may have to replace the harness to get one with the trans connections added, but I would bet that it would be cheaper than buying and adding in a separate trans controller.
 
With already having the factory ECM for the 6.0, I would buy a harness from BP automotive. ( I believe that is the brand that my buddy uses in his swaps.)
They will sell you a harness that will control both together.
However, you will need someone to do some work in the ECM or be able to do it yourself. Do you know who worked on the factory ECM to make it stand alone?

It wouldn't take much money to get another ECM if needed. At least not in my area. But you it requires buying credits to unlock the ECM when using HP tuners software.

Otherwise, I would look at a Holley harness and computer so that you can make changes yourself. But you would need to start at ground zero on the initial tuning for the engine and transmission.
 
205 stupid easy to build . i have a step by step in the advanced section .

the 700r4 will be better gear ratios over the th400/4L80 ratios . i would build the 700 my self if not using crazy hp or towing a lot .
 
tarussell said:
Gotcha,
The easiest way is to use the one year only ( ‘91 K30 or I should say V3500 to be absolutely correct ) adapter.
I’m assuming that your NP 205 is an ‘85~’91 round pattern long 32-spline input case ?

You can also use an ‘85~’91 1/2 or 3/4 Ton short mount crossmember and just drill through holes in the frame in the correct locations just as GM did originally.

You can achieve all this with OEM parts and will look somewhat factory appearing.
Click to expand...
The NP205 is the original 1972.
For the cross member that's easy enough Thankyou.
 
ashman said:
The wiring harness for the 6.0 may or may not have the connections added to it to control the transmission. You may have to replace the harness to get one with the trans connections added, but I would bet that it would be cheaper than buying and adding in a separate trans controller.
Click to expand...
Gotcha. I talked to my transmission guy that's rebuilding the tranny and the transfer case. He did this same set up (6.0LS, 4L80E and NP205) in his 73 blazer a couple of years ago. So I'm gonna be picking his brain to find out the route that's best for what I have.
 
6872xtc said:
With already having the factory ECM for the 6.0, I would buy a harness from BP automotive. ( I believe that is the brand that my buddy uses in his swaps.)
They will sell you a harness that will control both together.
However, you will need someone to do some work in the ECM or be able to do it yourself. Do you know who worked on the factory ECM to make it stand alone?

It wouldn't take much money to get another ECM if needed. At least not in my area. But you it requires buying credits to unlock the ECM when using HP tuners software.

Otherwise, I would look at a Holley harness and computer so that you can make changes yourself. But you would need to start at ground zero on the initial tuning for the engine and transmission.
Click to expand...
I'm still in contact with the company that programmed the 6.0. I will be using them again so that will help a ton. I will look into BP automotive Thank you.
 
sweetk30 said:
205 stupid easy to build . i have a step by step in the advanced section .

the 700r4 will be better gear ratios over the th400/4L80 ratios . i would build the 700 my self if not using crazy hp or towing a lot .
Click to expand...
I will have to look for those instructions.
I already picked up the transmission and its with the shop now getting rebuild. The 700R4 was rebuild for the 350 by the P/O. solid transmission. I will just sell it to help pay for this part of the build. Thank you for the advise.
 
Update. I had to get a 4l60 transmission harness and have it repined for a 4l80. This harness is separate from the LS motor harness. The transmission is in. I ordered a Lokar case mounted shifter. The Np205 has been machined and rebuilt. I bought a transmission cross member from dirtydingo.com. Probably gonna have to have the drive shafts adjusted. or just order new ones. Had the PCM bench flashed for the 4l80. after the drive shafts and a tune she will be good to go. Thank you for all the info guys. I'm excited to have her back on the road.
 
sorry you purchased dirtydingo products . he burned me a long time ago and offered to pay me off to be quiet about his crap sub par product .

hope you make out better tho . and looks like the build is going good .
 
sweetk30 said:
sorry you purchased dirtydingo products . he burned me a long time ago and offered to pay me off to be quiet about his crap sub par product .

hope you make out better tho . and looks like the build is going good .
Click to expand...
Oh man that sucks. I have their motor mount for the 6.0 and now this one. The motor mount is pretty solid and hast given me any issues.
 
SKUBASTEVE1010 said:
Oh man that sucks. I have their motor mount for the 6.0 and now this one. The motor mount is pretty solid and hast given me any issues.
Click to expand...
cause he had to re design the whole unit after i pointed out his crap design and super bad weld joints . yes it was years ago . but his customer service was super bad .
 
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