The 700R4 and 4L60E transmissions share many components in common. The 700R4 is non computerized and the 4L60E is computerized. However, many components and upgrades can be made interchangeable.
Based on the fact that one is computerized and one is not, the cases, valve bodies and pumps are the primary non interchangeable items. I think a lot of people agree with me that the these two units are two of the best transmissions ever produced.
They are versatile highly upgradeable transmissions. Many of the hard part upgrades, except for the pump, case and valve body, apply to both units. These units have been upgraded by the factory and research and development companies like TransGo for many years and reasons, turning them into highly reliable, durable units that can be purchased in the rebuilt transmission form for very affordable prices.
One of my favorite upgrades, especially if the vehicle is used for commercial work, or if the low/reverse planetary is damaged, is to replace the low/reverse planetary with a new version, (circa 2002 ish), that is 20% stronger and has a better (lower) ratio for more pulling power.
Low planetary assemblies are prone to failure in these transmissions. Not because the planet is weak, but more due to lack of lubrication flow to this area. By and large, when we performed a rebuilt transmission job to a 700R4 or 4L60E, we always installed a Transgo upgrade kit.
The SK-4L60E solves and prevents all of these issues:
Corrects/Prevents/Reduces: FIXES Code 1870 Trouble light & Hard 1-2 shift. No lockup or 4th. Fixes harmonic bounce that wears out pump and valves and causes shuttle shifts. Low/Rev planetary burnup, Fwd and L/R clutch burnup; 1-2 bump; double bump; slide-bump.Has new design Isolator/Conv Valve that works Perfect in worn bore w/o special tools or machining. (Transgo.com)
The SK 700R4 Shift Kit solves and prevents:
Corrects/Prevents/Reduces: Absolutely prevents Stuck TV valve. Late shifts, downshift clunk; 3-4 clutch failure; no lockup; 2-4 band failure; early shifts; 1-2 slide/slide-bump; reverse delay hot; 2-3 cutloose; Low/Reverse planetary burnup,
reverse clutch failure. 83-87:
Kit lets you make Converter lockup-no wires needed.
The deal with the low/reverse planetary setup concerns include, adding one more pinion gear to the redesigned planetary housing. This setup has five pinion gears instead of four pinion gears. What this means is that the one extra pinion gear adds 20% more strength to the part. That in itself is a bonus and practically a no brain-er in Chevy transmissions, especially if the planetary was burnt up. In reality it is a great upgrade for another reason too.
By adding an extra pinion gear to the planetary assembly, we end up with a new and better first and reverse gear ratio. A much more desirable ratio for accelerating and pulling heavy objects. More ‘low end pulling power’, as we call it. It makes a heck of a difference.
The upgrades seem to be endless, especially when you purchase a rebuilt transmission. The best time to upgrade is when a transmission is apart and the whole upgrade process can be applied.
The other viable upgrades will be discussed in future articles on our GotTransmissions.com blog. Stay tuned. By understanding that paying a fraction more for a rebuilt transmission that is upgraded, will cost less in the long run, you are becoming an educated consumer. Enjoy.
BTW: An auxiliary transmission cooler coupled with the updates is the best recipe available for reliabilty and dependability, which ultimately makes an upgraded rebuilt transmission, with an auxiliary add on external cooler installed an affordable long term solution.
