Trans help needed

I am trying to help a friend out here...

The car is a 1993 Caprice wagon that he loves it has a 305 but was shooting trans fluid all over from convertor. He brought it to a trans shop and they said he spun a bearing and convertor + pump bad ... Seen as the car is little value he suggested a junkyard swap that they did. with a trans from a van ?

He gets car back and the speedometer is all wacked so here is where I come in .... I looked at it and I was told its a 700r4 .. it took me 3 seconds to feel like the convertor is locked all the time I think? let foot off brake and you go to 30mph at idle according to speedo obviously you are only going about 4mph in reality circling a few blocks cost 400miles 100+ mph it pins itself on the odometer and the trans feels off but runs and drives fine...

It has to be a computer problem right? i can't find anything on how to reprogram the computer for this car or trans it is a TBI 305 all stock... I want to maintain the speedometer if all possible only thing I can find is on replacing the speedo gears but I think that is not the problem by the way the car feels like it is a constant locked..

I am an old style shade tree mechanic not an electronic anything person so an help I can give him would be great they use the car for animal rescue the trans shop will not help or look at it anymore :( I went over to see them to try and work it out but he had no clue although he made up some complete BS story. So here I am ... I loaned them my tahoe till I find an answer please help I love my tahoe and it will go to hell with smelly rescue dogs in the back.

The VSS (vehicle speed sensor) on the transmission is probably the wrong type. Some were optical and some were a magnetic tacho-generator. You should be able to refit the VSS from the original trans (if it's still available) and solve the issue.

The trans is a 4L60, which is a variant of the TH700-R4. If the VSS output is pulsing 100X what it should, the transmission will go into TCC lockup at about 5MPH actual speed.

There are three possible types of VSS signals used by the ECM for various TH700-R4 and 4L60 transmissions:

1. The two-pulse (2000 pulses per mile) square wave D.C (optical) used on all TBI engines thru 1992, all computer-controlled-carbureted engines, and on most 1985-1989 TPI engines.

2. A four-pulse (4000 pulses per mile) sine-wave A.C. (Tacho-generator) required by the 1990-1993 TPI, 1992-1993 LT1 engines, and 1990-1993 Camaro 3.1/3.4 V6 engines.

3. A 40 pulse per driveshaft revolution speed sensor used on 1993 and newer trucks with automatic transmission, 1994 and newer rear drive cars with the automatic transmission

In addition, manual transmissions used a fourth type:

4. A 17 tooth per driveshaft revolution speed sensor used on 1993-1997 LT1 engines with the Borg-Warner 6-speed transmission. An 11 tooth reluctor ring is used on 1993 LT1 engines with the
Borg-Warner wide ratio (3.35 First gear) 6-speed transmission.

I appreciate you taking the time to respond. The VSS that was original to the car I am told was gear / magnetic driven according to the shop. I called and asked to swap VSS for the trans they told me it won't work don't bother good luck. basically they have their money bye bye..

I am assume that the trans I now have is a 40 Pulse according to your information.

Stamped on the sensor is 8654750 A few photos of the part from the trans I have are below. Is there a replacement sensor that I cna put in this ones place that pulses less? or am I screwed to take the tailshaft off and replace the whole part

I am really confused I can not seem to get a straight answer and I appreciate what I have learned here I have somewhat of a direction now.

Any advice on what to do now would be greatly appreciated cause I have a car on ramps in my driveway that is not mine and I don't want dripping tranny fluid

http://i73.photobucket.com/albums/i231/MDA_/cars/Parts/DSCF3613.jpg

http://i73.photobucket.com/albums/i231/MDA_/cars/Parts/DSCF3615.jpg

http://i73.photobucket.com/albums/i231/MDA_/cars/Parts/DSCF3617.jpg

go to a scrap auto salvage yard and give them the details ..they should have a damaged tranny of this year / model for parts , to get this resolved .