Automatic Transmission - Quick 4l80e question
11-23-2007, 10:07 PM
I was reading over the writeup on the 4l80e install and was alittle unsure about the vss wiring. When I get the speartech harness which comes with the main plug adapter and the vss harness do I just hook up the front vss with the new plug that I got or do I also reuse my stock vss plug in the rear of the trans. So another words do I have to hook up both vss on the 4l80e? Or do I just have to run the new wires that come with the harness from the pcm to the trans. Thanks.
11-23-2007, 10:32 PM
If you are installing the Speartech harness it should be a snap. Those guys know what they are doing! I've installed a few different harnesses they have built for different applications and highly recommend them.
You would plug in both sensors if you are running a Factory PCM.
11-24-2007, 09:04 AM
Ok so I just plug my new speartech vss harness to the front vss of the 4l80e like the writeup says and put my stock plug into the back of of the vss? Im going to be using the factory pcm with a hp tuners rewrite from 4l60e-4l80e.
11-24-2007, 09:45 AM
Yep, do that. I don't think you'll run into any issues.
I have not run into the symptoms described in the write up personally. If you do, disconnect the battery for a few minuteds in order for the PCM to reset and connect the harness as described in the sticky referenced here and see what happens.
11-24-2007, 11:04 AM
You have to plug in and run the speed sensor wiring to the front speed sensor (from the PCM) on the 4L80E, the 4L60E doesn't have an input speed sensor.
11-24-2007, 04:49 PM
Yea I pretty much needed to know if I need both sensors hooked up I know I need to run a new wire from the pcm to the 4l80e. Thanks.
11-24-2007, 04:58 PM
Plug in your old rear sensor to the rear sensor on the 4L80E, and then wire in the new front sensor. The PCM will be looking for it when flashed with the 4L80E program.
You don't have to use the Speartech harness for the main connector, you can unpin 3 wires, fold one back, and swap the other two for the 4L80E.
11-24-2007, 07:07 PM
Cool thanks for the info. I will probably just buy the speartech harness as it comes with both the vss stuff I need and the main harness adapter.