700R4 4L60E No Reverse.
Start your car put the transmission in Reverse and nothing happens. It was fine earlier. What happened? If you were to drive the vehicle forward, you may also notice that you no longer have second or fourth. This can be confirmed because your shift from first to third will be late totally skipping second and there will be no shift to fourth. The most likely culprit, a broken or stipped out sunshell This is a very common problem with this transmission and the repair unfortunately is to remove the transmission and disassemble it. Depending on mileage you will probably want to rebuild the transmission at this point so you are also going to need a 700R4 Rebuild Kit  or 4L60E Rebuild Kit The sunshell I referenced is called "The Beast". It is the heavy duty version and will last for years without any problems

4L60E has 1870 code

Your driving along and suddenly the check engine light is shining brightly. The transmission still shifts but the shifts are harsh. Upon a check of the codes, you find an 1870 TCC slip, converter overheat. This does not mean a transmission rebuild. There are many reasons for an 1870 code the most common being worn valves in the valvebody. In order to achieve PWM (pulse width Modulation) the valve in the valvebody is stroked many times. Actually thousands of times a minute. This causes severe wear in the valvebody and loss of pressure. If this has not been occuring too long, the repair can be as simple as a Transgo shift kit to repair and get pressures back to normal. While you are in there the next step should be to replace the solenoids since they can also cause low pressure problems as they work just as hard as the valves. These repairs can be done with the transmission still in the vehicle and the repair is alot cheaper then a full rebuild!!

4L60E Transmission Rebuild kits

Performing a complete rebuild of your 4L60E or just freshining it up, you need the right kit for the job. So you take it apart and everything looks good. Friction material, Steel plates, band, all hard parts but you want to replace all the gaskets and seals to freshen it up. 1993 to 1997 overhaul kit with frictions or 1998 to Present overhaul kit with frictions is a nice kit to freshen up your transmission. Need to do a complete rebuild? 1993 to 1997 Super rebuild kit or 1998 to Present Master overhaul rebuild kit is a complete kit that gives you everything you are going to need for your rebuild. The overhaul kit is made by Precision International an OE supplier of overhaul kits. This is the most complete overhaul kit you can buy. It contains all the gaskets, seals and sealing rings for your rebuild. The Friction module is made by either Borg Warner or Raybestos, both OE manufacturers of friction material. All in all you will be replacing your old wornout parts with quality parts that will last and last. Top this off with a Transgo shift kit to compensate for worn valves and valvebody and your transmission will be like factory new!!!