For those running the older 4L60 trans on their LS swap

[bobbylog]

Don't know if its the problem, but i have not connected the speedo wire yet to my cluster.

You don't need to wire the speedo only the VSS signal to PCM and a tune for 4l60e.

[kewljay223]

You don't need to wire the speedo only the VSS signal to PCM and a tune for 4l60e.

yeah. like he said. thats all i had to do to get my trans running first time around. just make those two things are good and you should be on your way... BUT... not trying to scare you but this happened to me when i did the 80e swap.... i too bought mine off craigslist and the guy told me that it worked just fine... well when i finally got everything hooked up, it too wouldnt shift out of first. in fact it was in first not matter what...even in reverse it would go forward!! took it to the trans shop to fix and the planets/clutches were shot and was "welded" in first gear cuz it got to hot or something... needed a full rebuild. hope that you didnt get royaly screwed from craig like i did, but just wanted to point out that might be a possibilty.... good luck man

[droopyzda1]

I got the motor, wire harness, pcm and flex plate off Craigslist. The only reason I had to rebuild the heads was cause my old man tries to help me remove a broken exhaust manifold bolt and ended up drillingall aroundit and o down to the water jacket. Had to get another set of heads (off Craigslist) sent them to be rebuilt. The trans is originally off the truck. I wanted to keep it cause of budget and the previous owner told me it was rebuilt a couple yes back. When I removed the old transfer fluid, it was red and clean. When I removed the pan to change the internal harness they was just some tiny black particles on the magnet which I heard is normal.So aside from the VSS and speedo,any other wires that must be connected from the LS stand alone harness to the older 4L60 ?

[droopyzda1]

I also dont know if it matters, but there is a plug that was cut off from my original harness that I left all the wires there just in case. I was able to trace tha lt harness to the red and blue connectors. Some of the wires were for one of the O2 sensors in which I soldered a new pigtail to it. The other wires I labeled and tucked them away. Those were for the digital gear shift indicator. But in my case, its mechanical. Could it be that I missed some of those wires? As far as my trans wiring from yhe ls stand alone goes, I only connected the round plug and the vss.

[Mickeymotormount]

Not sure if the PCM uses the shift switch on the side of the trans to allow the trans to shift out of first gear automatically. It could be a possibility though. I retained my selector switch not kinowing if it would work without it.

Another possibility, although remote, is that the VSS is defective or the harness to the VSS could be at fault.

I had a similar problem with my swap when I first started to drive it, no upshift from 1st to 2nd. Turned out I wired the VSS to the PCM and the DRAC box to allow the speedo to work. After removing the wires to the DRAC box and leaving the PCM wires on the VSS, the trans shifted perfectly.

[droopyzda1]

Thanks Mickey. I will double check the harness going to the VSS and will check to make sure it is working. As for as a DRAC box is concerned, isn't that for cruise control? If it is, I don't have it on mine cause its a plain jane trim, work truck.

[kewljay223]

im pretty sure it is used for both. it reads the pulses that the vss from the transmission sends out. it then deciphers it and sends a new signal to the speedo and also to the crusie control module. on the newer trucks there is no drac box because the pcm now does the deciphering. so you have two options to control the speedo on our older trucks (which i didnt find out until later) either by the new pcm or the old drac box like original.

but im not sure why mickey had that problem because im doing the same thing he did originally. i kept the wires from my vss going to my drac so it could control the speedo and cruise like its supposed to. but the pcm needs signal also so it can control the transmission. so i just spliced into the vss wires and ran them to the new pcm also.... and both my 60e (worked) and my 80e i have now work just fine hooked up that way.... so i dont see how that could have messed up his shifting....

im willing to bet its the 4 gear shift wires that you dont have hooked up. they also go directly to the pcm.