94 Lifted Silverado 6.0/4L80e swap Build

Some updates...Been driving the truck up and down the road alot. Shifts better and better each time, I think it wasn't shifting good before because I did a fluid flush and it prob takes some time for all the fluid to work itself back into the valleys and grooves. I bought a autometer triple pillar pod for a temp gauge, oil pressure gauge, and air to fuel ratio. I will let you all know that it fit like a peice of CRAP. If you are going to buy one, and your are like me who is really picky and like a nice clean look to things, DO NOT BUY IT. I had to hack mine all up just to get it to fit. I will probably end up writing autometer because its a shame. One the good side, I did end up making it fit so its in its 95% stock location. The 2 main problems is it was hitting the windsheild, so you couldnt get it to clip into your a-pillar, and the bottom edge was too long by about a half inch (the edge thats near the speaker on the dash). Good thing i am a collision tech or I would have gave up on this stupid 60 dollar part. Ended up trimming it and grinding the edges down so I was able to clip it back in. Another bad thing: The black color. They dont make them in interior colors so i will probably end up getting some blue interior paint from LMC and spray it quick.

im still having shifting problems. right now i have the purple and green wire hooked up to the back of the transfer case then to the ls pcm. my speedo works but its not shifting. also where did you put the yellow/black/grey/white wire from the pns switch?

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Originally Posted by myzterray

im still having shifting problems. right now i have the purple and green wire hooked up to the back of the transfer case then to the ls pcm. my speedo works but its not shifting. also where did you put the yellow/black/grey/white wire from the pns switch?

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I will have to get u a pic for the rear vss. I don't have my pns switch wired up bc my truck is a 94. Is ur 4wd working? I can explain how I did my rear vss on the tcase but I think pics will b better. I cut nelsons rear vss connector and cut my obs connector . I took nelsons purple wires and put it with my blue wires I think from the obs. Then I took nelsons green wire and put it with the obs green I think. Then I put the stock obs connector on. So u will have two wires goin through a butt connector to one wire and then two. Wires goin through a butt connector to one then the obs connector

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Originally Posted by HPICamaroSS

I will have to get u a pic for the rear vss. I don't have my pns switch wired up bc my truck is a 94. Is ur 4wd working? I can explain how I did my rear vss on the tcase but I think pics will b better. I cut nelsons rear vss connector and cut my obs connector . I took nelsons purple wires and put it with my blue wires I think from the obs. Then I took nelsons green wire and put it with the obs green I think. Then I put the stock obs connector on. So u will have two wires goin through a butt connector to one wire and then two. Wires goin through a butt connector to one then the obs connector

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my 4wd wont work because i cut off the plugs that connect to the front driveshaft accidentally.

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Originally Posted by myzterray

my 4wd wont work because i cut off the plugs that connect to the front driveshaft accidentally.

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K heres 2 pics of how I did mine. The blue and purple wires in the nice clean wire loom is the LS rear vss wires. Then the dirty wire loom is my stock wires with green and blue I believe. Don't mind the red wires, those are for my neons. I have a question for you, what OBS wire(s) did you hook your LS speedo wire to?

Got exhaust ran today! And driving it to the shop I had a few problems (including blowing the water pump).

Hopefully I can get a few answers for my problems:

First, when the truck has been driven for a while and is up to temperature, i come to a stop sign and it will want to keep going and if i press the brake to try to stop it it will act like its going to stall out. So I have to put it in neutral. But when its cold i can stop and it will idle just fine with me on the brake.

Second, I cant get my speedo to work. I have tried hooking nelsons green speedo wire to my Light Blue w/ white stripe wire and nothing happens.

Third, my RPMS are way off. The tach is reading 1,000 when I am going 55 (using gps). Keep in mind I have 4.56 gears lol so I know that isn't right.

4th, when trying to confirm the RPMS with a scan tool hooked up to nelsonss obdII port, it says it can not communicate with the ecm. And the check engine light thats on their obd connector is lit up so I know it has power.


Other than those issues and the water pump, the truck drives like a dream. seems so smooth and takes absolutley no effort for it to take off. pulls really good on the top end for sure. its way stronger than my last cammed out crate motor. Ill get pics of the exhaust job, it looks really good i'd say we did a pretty good job going from the headers to a y merge pipe to a electric cut out to a single in flowmaster to dual out.

don't know how much help i can actually be since you have a 94, but on my 96 i have 2 wires coming from the c100 connector that both said vehicle speed signal, B5 & D4. one is green & the other green w/ white. the speedo wire coming off my nelson harness is green w/ white so i connected to my green/white & no speedo. connected it to the solid green, which is B5 & now my speedo works.

on the tach mine is doing about the same. it doesn't move till i hit about 3k RPM, then it only reads 1K. i saw myzterray used a 680 ohm resistor. i found 680k ohm & 680 ohm so i'm assuming it's just the 680 ohm. i'm going to hit up radio shack & see if i can get one & what happens.

i had a friend of mine come over with 2 scan tools. one really nice windows base & it worked fine. he also had a Mac & the Mac wouldn't communicate with it. i rented a code reader/scan tool from autozone this morning & it read just fine. the Mac tool also wouldn't communicate with another friend of mines harness.

hope you get your problems fixed. to me, all the final small things are harder to solve then getting the motor in everything mounted. all i have left on mine is the tach & all my factory gauges will be working, including the SES light.

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Originally Posted by HPICamaroSS

First, when the truck has been driven for a while and is up to temperature, i come to a stop sign and it will want to keep going and if i press the brake to try to stop it it will act like its going to stall out. So I have to put it in neutral. But when its cold i can stop and it will idle just fine with me on the brake.

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Did you wire the brake switch signal to the pcm...? The PCM need a 12 v when the brake are not being applied (the opposite of a standard brake light switch) This signal control the torque converter lockup.

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Originally Posted by HPICamaroSS

K heres 2 pics of how I did mine. The blue and purple wires in the nice clean wire loom is the LS rear vss wires. Then the dirty wire loom is my stock wires with green and blue I believe. Don't mind the red wires, those are for my neons. I have a question for you, what OBS wire(s) did you hook your LS speedo wire to?

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dont think it hooked up to anything honestly. once i plugged u th vss to the back of the transfercase the speedo worked. but its not smooth. its choppy kinda. i still cant get this thing to shift...i hooked up the trans range signal wire abcd now my gear indicator is acting weird.

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Originally Posted by bobbylog

Did you wire the brake switch signal to the pcm...? The PCM need a 12 v when the brake are not being applied (the opposite of a standard brake light switch) This signal control the torque converter lockup.

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How do I do that? I'm sure thats the problem because I havent done that lol

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Originally Posted by HPICamaroSS

How do I do that? I'm sure thats the problem because I havent done that lol

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I have never do that to but from what I've read you need a switch like this.
http://www.ebay.com/itm/TCC-BRAKE-SW...item27c42fbcc4
http://secure.ultracart.com/catalog/...f/KIT-1002.pdf
I've read that you can use a relay to but in my case I will just buy the switch.
Your nelsons harness is supposed to have 1 or 2 wire ready to hook to the switch.
Edit:

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For automatics with lock up converter, the PCM needs signal when brake pedal is pressed. However, the signal needed is opposite how you're brake lights work. The PCM wants 12v+ constant on this wire when brake IS NOT pressed, and OPEN Circuit when the brake IS pressed. If you vehicle was equipped with a lockup trans to begin with, you probably already have the proper normally closed switch mounted by your brake light switch. If you do not, you can use a relay to perform the same thing. On most relays, there are 5 terminals, 2 of them turn the relay ON when provided ground/power. There are then a normally open leg and a normally closed leg on the relay and a supply. By feeding 12v+ on the supply leg, and hooking the Brake Switch Signal wire to the normally closed leg, you will now have the correct signal for the PCM. When the brake is pressed, 12v+ flows to brake lights, tap into this wire, and run it to the relay to turn the relay on. This will cause the normally closed leg to become open, thus turning OFF the 12v+ signal to the PCM. When you release the brake pedal, the relay will turn OFF, and then feed 12v+ to the PCM.

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From Lt1swap.com http://lt1swap.com/wiringharness.htm
So you are supposed to already have a brake switch like this.

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Originally Posted by HPICamaroSS

How do I do that? I'm sure thats the problem because I havent done that lol

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Its real easy. Just find the brake switch in your truck. Its on the pedal up under the dash a lillte bit. And then look for the purple wire and splice the one from your swap harness to it and your done.

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Originally Posted by 92 6.0

Its real easy. Just find the brake switch in your truck. Its on the pedal up under the dash a lillte bit. And then look for the purple wire and splice the one from your swap harness to it and your done.

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Do you know which wire I have to splice it into on Nelsons harness? Because their harness is a 4 wire hookup, and that doesn't include a wire for the brake

Power may be coming from Blue PCM connector pin 19 or it may be wired into the power lead that is going to the 4 wire connector for 12v power, could be switched or always on.

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Originally Posted by HPICamaroSS

Do you know which wire I have to splice it into on Nelsons harness? Because their harness is a 4 wire hookup, and that doesn't include a wire for the brake

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This wire is supposed to be with the dash group speedometer,tach...Also did you wire your park neutral switch? The pcm need to know when you are in gears..

You don't have to have a PRNDL switch for it to work, there is a setting in HPTUNERS to turn the PRNDL device off.

http://i47.photobucket.com/albums/f1...5138457901.jpg

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Originally Posted by RedHeartbeat

You don't have to have a PRNDL switch for it to work, there is a setting in HPTUNERS to turn the PRNDL device off.

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I was sure you need it because you can adjust it in hp tuners in target idle tab thanks for the info!I learn something new here everyday!
http://imageshack.us/photo/my-images...nersidles.png/

http://img821.imageshack.us/img821/8...unersidles.png

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Originally Posted by RedHeartbeat

Power may be coming from Blue PCM connector pin 19 or it may be wired into the power lead that is going to the 4 wire connector for 12v power, could be switched or always on.

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Ok I'll try that thanks!

i have a Nelson harness too & didn't have to hook anything up to the brakes, & i don't have a neutral safety switch, & mine shifts & stops just fine.
how's your idle when you try to stop, is it high?

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Originally Posted by RPM Graphics

i have a Nelson harness too & didn't have to hook anything up to the brakes, & i don't have a neutral safety switch, & mine shifts & stops just fine.
how's your idle when you try to stop, is it high?

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My idle is just fine. Warm and cold. I dont have a accurate reading bc My tach is way off and I need to call Nelson to see if they can fix it/ recalibrate it with me sending my ecm back in. But I do know its idleing about right. Sounds like its between 600 and 1000. When I try to stop it might rev up a tad because it wants to leep forward but then ends up stalling if you dont put it in neutral.

Heres some pics of my 3" exhaust from the headers back to a y pipe, through a electric cutout, then a flowbasterd, then back to duals.

Does anyone know what this connector is for?!?? It is braided and shielded (has a protective caseing around it) And then it also has a black wire with a white stripe. What Im trying to figure out is where that black wire with the white stripe goes. I want to say its a ground but I am not rreally sure. The 2 wires coming out of that connector is purple w/ white stripe, and green with black stripe.

the first pic is an exhuast bung for my air fuel ratio gauge.

purple and green wires are your OBS speedo wires. Black with white is ground 99.9% of the time.

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Originally Posted by RedHeartbeat

purple and green wires are your OBS speedo wires. Black with white is ground 99.9% of the time.

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I bet thats why my speedo doesnt work then lol. I love solving problems. Hey red while you r online i need you to help clarify things about ur reply on my earlier post about the brake switch and torque converter unlock

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Originally Posted by RedHeartbeat

Power may be coming from Blue PCM connector pin 19 or it may be wired into the power lead that is going to the 4 wire connector for 12v power, could be switched or always on.

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So is that all I do is take pin 19 from the blue connector and wire it into the power lead on the brake switch?

no no no. The PCM would supply voltage to the transmission. I prefer that the power for the transmission comes from the brake pedal switch. Look for the lead on the brake pedal switch the has 12v with the pedal at rest and 0v when you push the pedal down. Did you see the recent posts I made for Myzterry about the wiring diagram for the transmission. I think it's terminal E on the connector that has a pink wire to it and it's supposed to have that 12v source going to it from the brake pedal.

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Originally Posted by RedHeartbeat

no no no. The PCM would supply voltage to the transmission. I prefer that the power for the transmission comes from the brake pedal switch. Look for the lead on the brake pedal switch the has 12v with the pedal at rest and 0v when you push the pedal down. Did you see the recent posts I made for Myzterry about the wiring diagram for the transmission. I think it's terminal E on the connector that has a pink wire to it and it's supposed to have that 12v source going to it from the brake pedal.

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No I didnt see your post on Rays Thread so I will go look at that. I understand that I need to have the brake switch with 12v constant and then once its pressed its an open circuit so 0v, so what do i do once I find that wire and confirm that is has 12v and then 0v when brakes r applied

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Originally Posted by RedHeartbeat

no no no. The PCM would supply voltage to the transmission. I prefer that the power for the transmission comes from the brake pedal switch. Look for the lead on the brake pedal switch the has 12v with the pedal at rest and 0v when you push the pedal down. Did you see the recent posts I made for Myzterry about the wiring diagram for the transmission. I think it's terminal E on the connector that has a pink wire to it and it's supposed to have that 12v source going to it from the brake pedal.

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Ok I think I get it now, all I need to do is run my brake switch wire to that terminal e on the tranny connector.. I found your post and yes it was terminal E, IF that connector is the same connector on my 4l80e.

hang on, let me verify for sure.

http://i47.photobucket.com/albums/f1...5232065888.jpg
http://i47.photobucket.com/albums/f1...5232110595.jpg


Wire C which is red goes to the shift solenoids on the 80e. It's been a while since looking at that manual. LOL

This is likely your schematic. I believe the other was for 92 and earlier. E "would" be the correct wire for your power to the noids.

http://i47.photobucket.com/albums/f1...5232540071.jpg
http://i47.photobucket.com/albums/f1...5232702325.jpg

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Originally Posted by RedHeartbeat

This is likely your schematic. I believe the other was for 92 and earlier. E "would" be the correct wire for your power to the noids.

http://i47.photobucket.com/albums/f1...5232540071.jpg
http://i47.photobucket.com/albums/f1...5232702325.jpg

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Awesome thx so much ur a great help

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Originally Posted by RedHeartbeat

no no no. The PCM would supply voltage to the transmission. I prefer that the power for the transmission comes from the brake pedal switch. Look for the lead on the brake pedal switch the has 12v with the pedal at rest and 0v when you push the pedal down. Did you see the recent posts I made for Myzterry about the wiring diagram for the transmission. I think it's terminal E on the connector that has a pink wire to it and it's supposed to have that 12v source going to it from the brake pedal.

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Hey Red I am working on this right now and I couldnt find any wires from my brake switch that have 12 volts at rest, then 0 volts when u press the brake. I have a yellow wire that is the opposite that has 0 volts at rest, and 12 volts when you press it down. Then I have 2 purple wires that have .95v at rest, and 0v once you press the pedal down. So I am not sure which wire I am supposed to use. Thanks again for all your help

I'm thinking it's the purple wire. Pink has 12v all the time and purple switches off when the brake is pressed. The other wire you're seeing may be brown instead of purple.

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Originally Posted by RedHeartbeat

I'm thinking it's the purple wire. Pink has 12v all the time and purple switches off when the brake is pressed. The other wire you're seeing may be brown instead of purple.

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Yup the pink with the stripe had 12v so I'll try hookin up the purple. Thx again

Truck is running/ shifting good, and when I come to a stop now it doesn't want to leap forward and stall out.

Still have a few issues.

No Speedo- Going to try reverseing the 2 wires on my rear vss on the t case.

Tach is still way off

When trying to confirm RPMS through a scan tool, the OBDII port cant make a communication with the ECM????? Is that because Nelson Locks it?

And last is a 4x4 issue. Back with my old setup with the 350 and 4l60, i could put it in 4x4 on the go with out a problem, it would hop right in gear whether it was 4L or 4H. Now when I try to do that, all it does is grind really bad so I have to shut the truck completly off and engage it. Even if the truck is in park or N it still grinds

Been driving around with GPS latley because your speedo doesn't work? Me too. Enough of that. Take your LS harness and find the rear vss connector with the Blue and Purple wires. Find your OBS rear vss connector with the Blue and Green wires. Connect the LS Blue to the OBS Blue. Connect the LS Purple to the OBS Green. Now access your vss buffer box located behind the glove box. It is the little white box. Find the solid blue wire. Cut it before it goes into the vss buffer box but leave enough room to connect a butt connector. Take you LS speedo wire and the blue buffer box wire and put them in one end of the butt connector, then put the other blue wire coming from the speedo in the other end. Should have a working tach then. It does cause your brake light to come on and I dont know why, but atleast you now have a working speedo. NOTE: If you unplug the buffer box it will cause your brake light to come on as well

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Originally Posted by HPICamaroSS

Been driving around with GPS latley because your speedo doesn't work? Me too. Enough of that. Take your LS harness and find the rear vss connector with the Blue and Purple wires. Find your OBS rear vss connector with the Blue and Green wires. Connect the LS Blue to the OBS Blue. Connect the LS Purple to the OBS Green. Now access your vss buffer box located behind the glove box. It is the little white box. Find the solid blue wire. Cut it before it goes into the vss buffer box but leave enough room to connect a butt connector. Take you LS speedo wire and the blue buffer box wire and put them in one end of the butt connector, then put the other blue wire coming from the speedo in the other end. Should have a working tach then. It does cause your brake light to come on and I dont know why, but atleast you now have a working speedo. NOTE: If you unplug the buffer box it will cause your brake light to come on as well

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^^

Have well over 500 miles on the swap! Runs awesome and I love it. Cant wait to head and cam it. A few small things I noticed....I have 3 vss connectors on Nelsons harness????? I am not sure what I am missing. I have the front one plugged in to the front of the tranny (4x4) and I have the rear vss plugged into the rear of the transfer case. Theres an extra vss connector thats inbetween those two. What am I missing