Which Transmission?

Which transmission is in the 1991 model wagons? 4L60E appears to be 1993+.
Is it the 700R4? Or the 4L60? Or are they the same thing?

The 91-93s have a 4L60/700R4. LT1 cars have the 4L60e. The 91-93 cars have a manual shift cable, and the 94-96s have the computer do the shifting. The tail shaft housing can be different on different years of the 94-96s. The 91-93s are all the same.

The 91-93 cars have a gear driven VSS as well. If you are changing tire sizes, you should re gear the VSS. There are two types of VSSs, one for the 34-39 tooth driven gears, and one for the 40+ tooth driven gears. You can also get 15, 17, and 18 tooth drive gears. The driven gears are difficult to find, and do not have a shaft on them. The pinion gears are a little easier to get. There is a chart, and formula on the Speedometer World site to determine what gears to use with what gear ratio, and tire size. The 94-96s have a tone ring and pickup, so are not adjustable. They use the computer to modify the signal for the tire size, and gear ratio.

The gears are marked for # of teeth both with an embossed number, and by the color of the gear. The FSM also has some of the possible ratios and tire size combinations in the transmission section.

Thank you Fred.
Your help is much appreciated. I guess I am going transmission shopping.