I have no idea what he did because everything you guys have said, and I have researched, has shown that there are two speedo gears and both are in the trans.
A few key things he said yesterday:
-He took out a 45 tooth gear (I told him stock was 44, he claims he thought it was 45. Also the local GM dealer he called said they don't make 44, but I've seen them online).
-He put in a 40 or 41 tooth gear (I don't know why, since thats going the wrong direction)
-When I mentioned that all I needed was a new 15 tooth drive he said, "oh that means I'll have to change the one in the tail of the trans and I'll need to order some new gaskets too."
From this, I would assume he changed the tooth driven (on the VSS of the 700R4) and didn't touch the tooth drive (in the tailshaft). This link shows how to change the two gears:
http://sethirdgen.org/vss.htm
According to this link below(post #10), my stock 9 bolt with a 3.27 gear and stock tires (245 50 R16) required a 44 tooth driven and a 17 tooth drive from the factory. That means all he needed to do was change the tooth drive in the tailshaft to 15 to match the aftermarket 3.70 rear gears that the original owner put in. Now he has to order another 44 tooth driven to put back in and get the 15 tooth drive to place in the trans tailshaft.
http://www.thirdgen.org/techboard/tr...eedometer.html