04 LM7 into 87 K5

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K5Rob

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Can anyone explain what they did to make their 4L60E work correctly with an NP208 ?? I have searched for weeks and can’t find anything. I know there are Several VSS options but when i dig a little deeper nothing seems to work correctly or put out the right signal. Which leads to poor performance, not shifting past 2nd gear, even no shifting. Is this why people scrap the 208 for a 241? Then of course the 4hi/low switch which seems a little more forgiving but I still am unclear on the tuning aspect - coming from a 2wd PCM would i need to source a 4wd pcm, or are the tables simply cut and paste for the tuner? Lastly I am assuming the factory shift linkage mates up to the 4L60E without too much hassle but I couldn’t find anything on this either. This is strictly for curiosity as i have decided to stick with the 700r4 for the above reasons.
 
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Vbb199 said:
Yea, this gets into what every LS swapper faces... the issue with 60e/80e swapping is you NEED vss , and if 4x4 you'll need your hi/lo switch off the t case


The expensive solution (due to rarity) is to run a passengers side drop NP241 OR 208 from a 90 or 91 suburban , (maybe k5?)
Which has vss.

Then run a 90/91 burb/k30/k5 electronic speedo instrument cluster .


Optionally---

You can visit dakote digital for a adapter to turn the cable speedo output on your 208 to VSS .... ORD might have also, idk.



The 700r4 is the easiest, cheapest methos (go on fleabay and price a np241 or vss 208 and you'll see why)
Click to expand...
IDK so throwing this out for someone who might shed some light. I'm pretty sure Camaros starting in 1984 used an adapter at the mechanical speedometer location that went in just like a mechanical drive but put out vss for electric speedo. Anyone,anyone,Bueller, Bucket.
 
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Vbb199

Vbb199

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Speedometer 8K Pulse Generator

Dakota Digital manufactures digital instrumentation and accessories for the automotive, motorcycle and car audio enthusiast.
www.dakotadigital.com


The adapter to give the PCM a speedo signal.

The pulses per revolution (a calculation based off of the number of teeth on the reluctor wheel inside your transfer case) is a programmable variable inside your P59 pcm.

As is the VSS pulses per mile, gear ratios, tire size and axle ratio.
 
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K5Rob said:
Then of course the 4hi/low switch which seems a little more forgiving but I still am unclear on the tuning aspect - coming from a 2wd PCM would i need to source a 4wd pcm, or are the tables simply cut and paste for the tuner?
Click to expand...


the tables for 4x4 stuff should be in the PCM by default..

edit, i looked in the tune repository on HPtuners website, and a 2wd 04 truck does have the 4x4 stuff in it. you should be good. its not much thats really needed... its just torque calculations, the most important part is the VSS signal
 
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There is also a low 4x4 shift table ,

It tells the trans what mph to shift when in low 4x4.
 
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Vbb199 said:
There is also a low 4x4 shift table ,

It tells the trans what mph to shift when in low 4x4.
Click to expand...
So if using the 4L60E and NP208, the PCM needs VSS from the transmission, transfer case or both?

Would I keep the factory VSS on the transmission plugged in and also add the Dakota Digital pulse generator at the transfer case cable input?
 
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K5Rob said:
So if using the 4L60E and NP208, the PCM needs VSS from the transmission, transfer case or both?

Would I keep the factory VSS on the transmission plugged in and also add the Dakota Digital pulse generator at the transfer case cable input?
Click to expand...

If im not mistaken your 2004 2wd 60e has the vss output at the tailshaft housing.

You'll be removing that to mate the 208 to it.

THe pulse generator goes where the old speedo gear housing went on the 208
 
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Vbb199 said:
If im not mistaken your 2004 2wd 60e has the vss output at the tailshaft housing.
Click to expand...
Yes it does, good call. So i am wondering now if i should keep the 4L60E or the 700r4
 
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All i found when researching was problems getting the 4l60e to work correctly. Maybe just bad tuning?
 
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K5Rob said:
So if using the 4L60E and NP208, the PCM needs VSS from the transmission, transfer case or both?

Would I keep the factory VSS on the transmission plugged in and also add the Dakota Digital pulse generator at the transfer case cable input?
Click to expand...
When I did my 4L60E + 208 combo all of the information I found claimed the Dakota signal wasn’t good enough for the factory PCM to shift correctly.

I ended up with a custom VSS and reluctor wheel from a 241 and modified my tail housing because I couldn’t find an adapter.

You must be registered for see images attach



Now there’s an adapter that mounts in the Speedo gear hole for like $150

https://www.walterseandp.com/product-page/np208-electronic-vss-conversion-kit-r2
 
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CalSgt said:
When I did my 4L60E + 208 combo all of the information I found claimed the Dakota signal wasn’t good enough for the factory PCM to shift correctly.

I ended up with a custom VSS and reluctor wheel from a 241 and modified my tail housing because I couldn’t find an adapter.

You must be registered for see images attach



Now there’s an adapter that mounts in the Speedo gear hole for like $150

https://www.walterseandp.com/product-page/np208-electronic-vss-conversion-kit-r2
Click to expand...
Thanks CalSgt. The Dakota Digital signal not being good enough is what I found too.

So then the Walters piece would take care of the VSS needs, and my tuner should be able to make everything work? It does look like I would lose my cable driven speedo though??

Then all I would need is an output shaft swap, 208 adapter, and wire up my brake switch. Am I missing anything else?

What about this adapter from ORD, would this suit the VSS needs of the PCM and allow me to keep the cable driven speedo?

www.offroaddesign.com

6 to 4 Bolt Adapter With VSS for the '97+ GM 4L60E/4L65E/4L70E

6 Bolt to 4 Bolt Adapter With VSS for the 1997-Current GM 4L60E/4L65E 4 Speed Automatic Transmission Adapter Kit. Adapts late 4WD 4L60E six bolt pattern to early 4L60E/700R4 four bolt pattern. Includes GM 40 pulse/rev electric speed sensor. Useful for adapting older NP205/NP208 transfer cases to...
www.offroaddesign.com www.offroaddesign.com
 
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Vbb199

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For what its worth, theres several threads with "how-to's" and success stories on using the dakota digital pulse generator with LS based PCMs ..... all on the hptuners forum

Hptuners is the goto software for tuning OEM type PCMs... its the one i use, probably also what your future tuner uses.

Its doable, and has been done with the dakota digital adapter

But i do understand looking into other avenues if thats what you desire..
 
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Vbb199 said:
For what its worth, theres several threads with "how-to's" and success stories on using the dakota digital pulse generator with LS based PCMs ..... all on the hptuners forum

Hptuners is the goto software for tuning OEM type PCMs... its the one i use, probably also what your future tuner uses.

Its doable, and has been done with the dakota digital adapter

But i do understand looking into other avenues if thats what you desire..
Click to expand...
Vbb I definitely appreciate all the advice. I am mainly trying to avoid any tuning type complications as the tuning portion of the build is outside of my scope of abilities. Since i would need an adapter anyway i think the one that is machined for the vss is a good way to go. Mainly asking if there is anything i am overlooking before i pull the trigger. I had a buyer lined up for my 4L60E but would prefer to keep it if this will solve the VSS issue and I can run my cable driven speedo off the 208 in its original location. I had everything lined up for the 700r4 but the parts are unopened and still returnable. Keeping the 4L60E, if all i need is the adapter with vss kit, and an output shaft swap, would save me a few hundred bucks.
 
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K5Rob said:
would prefer to keep it if this will solve the VSS issue and I can run my cable driven speedo off the 208 in its original location.
Click to expand...

there might be something major im missing here, but if you use the VSS adapters in place of the cable "box" , you cant run a speedo cable also, unless maybe you do like what that guy above did. It appears he can have his speedo cable for his instrument panel as well as VSS for the PCM

Because if you use solely VSS, then you have no speedometer, which puts you needing a 90-91 instrument cluster from a burb k5 or 1 ton
 
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