Can an early 4L80e work with an LQ4?
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Can an early 4L80e work with an LQ4? Hi,
So i have just realized I may have have made a big mistake in my build,
When I bought my LQ4 engine from a breakers yard they through in 4L80e to go with it and I sent it off to be rebuilt and have a special output shaft fitted, I have now got it back from the transmission shop and have just realized that it is an early (1994) and not the later type which was meant to go with my 1999 LQ4. I am going to be OK using this with an LQ4 or am I going to have to change it? I have already put a lot of money into this transmission and don't really want to have to swap it if i don't have to?
Thanks
Sam
So i have just realized I may have have made a big mistake in my build,
When I bought my LQ4 engine from a breakers yard they through in 4L80e to go with it and I sent it off to be rebuilt and have a special output shaft fitted, I have now got it back from the transmission shop and have just realized that it is an early (1994) and not the later type which was meant to go with my 1999 LQ4. I am going to be OK using this with an LQ4 or am I going to have to change it? I have already put a lot of money into this transmission and don't really want to have to swap it if i don't have to?
Thanks
Sam
Im not sure with the 4l80e but I know the 4l60e older versions will not work with the Ls style PCM unless something has changed.
It will bolt up but im not sure if the PCM will control it.
It will bolt up but im not sure if the PCM will control it.
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Thanks for the response, do you know what on the PCM is different? I am guessing it has something to do with the park neutral switch that goes on the selector shaft as this early unit has a shorter shaft that won't reach through the switch?
but im also curious now because I plan to do a 4L80e in the future!
Thread Starter
Teching In
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Did some searching around and I can get a later style Shift Selector Shaft, so i can fit the park neutral switch, other than that it looks electrically the same, so hopefully it should work.
https://www.ebay.co.uk/itm/New-4L80E...gAAOSwUyBbRhmd
https://www.ebay.co.uk/itm/New-4L80E...gAAOSwUyBbRhmd
Thread Starter
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Hi,
So i have just realized I may have have made a big mistake in my build,
When I bought my LQ4 engine from a breakers yard they through in 4L80e to go with it and I sent it off to be rebuilt and have a special output shaft fitted, I have now got it back from the transmission shop and have just realized that it is an early (1994) and not the later type which was meant to go with my 1999 LQ4. I am going to be OK using this with an LQ4 or am I going to have to change it? I have already put a lot of money into this transmission and don't really want to have to swap it if i don't have to?
Thanks
Sam
So i have just realized I may have have made a big mistake in my build,
When I bought my LQ4 engine from a breakers yard they through in 4L80e to go with it and I sent it off to be rebuilt and have a special output shaft fitted, I have now got it back from the transmission shop and have just realized that it is an early (1994) and not the later type which was meant to go with my 1999 LQ4. I am going to be OK using this with an LQ4 or am I going to have to change it? I have already put a lot of money into this transmission and don't really want to have to swap it if i don't have to?
Thanks
Sam
The PCM wants to see a park and neutral signal from that switch, and the body side (has nothing to do with the PCM) needs a reverse light switch. Usually aftermarket shifters have switches to be used for this.
The PCM programming should be changed to expect only a park/neutral signal. Can you skip all this? Sure, it will just idle weird for a few seconds when going from park to a gear and it'll idle off the main spark table instead of the 'in park' table.
The electrical should plug right in. There shouldn't be a rebuilt 4L80E with the old style connector in existence these days, but you never know I guess. I don't think the '94 ever had the old style anyway.
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Will it bolt up? Yea, it has the same transmission to engine mating area as a turbo 400 from 1966 (yes 1966) to the end of production, same with every th350, 700R4, etc. It just needs the right adapter and flexplate.
There are no bolt holes to mount the switch to so don't worry too much about the selector shaft length. Keep the short one.
The PCM wants to see a park and neutral signal from that switch, and the body side (has nothing to do with the PCM) needs a reverse light switch. Usually aftermarket shifters have switches to be used for this.
The PCM programming should be changed to expect only a park/neutral signal. Can you skip all this? Sure, it will just idle weird for a few seconds when going from park to a gear and it'll idle off the main spark table instead of the 'in park' table.
The electrical should plug right in. There shouldn't be a rebuilt 4L80E with the old style connector in existence these days, but you never know I guess. I don't think the '94 ever had the old style anyway.
There are no bolt holes to mount the switch to so don't worry too much about the selector shaft length. Keep the short one.
The PCM wants to see a park and neutral signal from that switch, and the body side (has nothing to do with the PCM) needs a reverse light switch. Usually aftermarket shifters have switches to be used for this.
The PCM programming should be changed to expect only a park/neutral signal. Can you skip all this? Sure, it will just idle weird for a few seconds when going from park to a gear and it'll idle off the main spark table instead of the 'in park' table.
The electrical should plug right in. There shouldn't be a rebuilt 4L80E with the old style connector in existence these days, but you never know I guess. I don't think the '94 ever had the old style anyway.
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