Gotta drop the cradle on my 3800 car again...

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In order to be able to shift into 1st gear, I had to monkey with the shift linkage a bit. And now the detents in the transmission don't match the detents in the shifter (which was meant for use with a TH-125 3-speed auto transmission).

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I went on another test drive today. It was going to be a long one, but my engine started idling very fast, so I went back home and put my scanner on. It said "Vehicle speed sensor failure". My "new" transmission already had a speed sensor in it, so I had left it in. So now I have to get the one from my old transmission and put it in, and since the speed sensor for the 4T60E is under my low mount alternator, I'll have to remove that. If it isn't one thing, it's another.

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I replaced the VSS with the one from my old transmission, and it seems to work OK. Next I did a little web searching about my probelm (having to shift into 1st to take off, and I found someone discussing the same problem. He tried disconnecting his vacuum modulator, and it fixed his problem. So I disconnected mine, plugged the vacuum line to avoid a vacuum leak, and went on a short test drive. Well, that seems to have fixed it. There's just a little bit of slip if you take off with a heavy throttle (which you don't get if you physically shift into 1st, but other than that, it shifts perfectly normally. Without the vacuum modulator, it shifts crisply (like with a shift kit?), but I certainly don't mind that.

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Today I took the car on a test drive up I985 to where it ends and turns into Highway 23 and back down to home. I had no problems, so I hereby pronounce the transmission not perfect, but Ok.