The problem is that the 700R4 is controlled by the TV cable, which is basically just a basic throttle position sensor. They identical in terms of length and where they bolt to the crossmember. The biggest difference between these two transmissions is going to be the way that they are controlled. This makes either of them a fantastic replacement for the TH350 and TH400 transmissions. It’s short.ĤL70E– Even more improvements over the 4L65E.īoth transmissions use the same exact gear ratios with a final overdrive of.

If you want to know more about what they were, just click the article. This is due to the fact that it is newer and all the bugs were worked out.ĤL60E- The 4L60E was almost identical to the 700R4 at first, but gradually began to look different as improvements were made.ĤL65E Many Upgrades were made for reliability and power handling. It’s still not computer controlled, but it is more desirable. Here is the complete evolution of this transmission design through many names.ħ00R4– This is the original design that made its debut in 1982.ĤL60- Same transmission as the 700R4. Remember this, the biggest difference between these transmissions is computer control. There are solutions to get around this, but they aren’t very cost effective. This makes these transmissions incompatible with one another when looking to replace your transmission. When the 4L60E made it into production, it went to electronic control. Throughout that whole period, they have constantly improved. From the early eighties until quite recently it has been in service in GM passenger vehicles and light trucks. It is better to think of them as the continuation of the same design. Good luck and thank you for using Fixya.The 700R4 and 4L60E transmission are not siblings. Either way the trans needs to come out and torn down and it will be easily found what went. Not the beef sun shell eitherīecause you have rev., a broken sun shell would cause no 2nd, 4th and If the pump was bad you would have no line pressureĪnd it would slip in rev. If you have reverse then it is not the pump. If you pull the pan and find chunks of iron and steel, then that is probably what happened. If no manual 1st then your sprag is not what broke. If you can shift threw the gears manually then, Use the forward sprag unless the LO/Rev clutch is engaged.i.e. Manual 1st to manual 2nd then 'D' then 'OD'? Only 1st and 2nd gears Try not to run or drive the car or further damage could result.ĭo you have manual 1st? If so, can you shift through the gears.i.e. No forward movement in OD or D, but L2, L1 and R work: Forward sprag is broken.

Picture.of corvette servo 700r4