This is the second article in a two part series on popular transmission swaps into your early Bronco. The first article focused on several manual choices for those who like to row their own gears. This second article is for you folks who prefer the ease and drivability of an automatic.
The 3 speed manual or C4 automatic that came stock in the Bronco serve their purpose, but they’re not the best to be had. Some people want a stronger, more reliable transmission with ultra low gearing for those tough trails. For others, street performance is more important and a highway friendly overdrive becomes essential for those long commutes. And then there are some (all?) of us that want both!
This article is meant to give you some basic information to help you decide which transmission is best for your needs. There are several fine points to each conversion that aren't covered here, such as TV cables, shifters, wiring, etc. Once you pick a tranny to go with you should research it thoroughly with the company providing the adapter.
Automatic transmissions are complicated and can be very daunting to the novice mechanic. It's recommended that you have a competent shop do a rebuild since many of these units have weak points that a qualified rebuilder should be able to correct. Typically a new torque converter should also be installed, and you should research your choices here as well. The torque converter can have a significant impact on how your Bronco drives. As with most transmission swaps, headers can cause all sorts of grief. If you have headers, or plan on installing them, you should measure thoroughly so you aren't surprised when you try to shoehorn that new tranny in.
This article assumes a small block Ford V8 engine is being used and the Dana 20 transfer case retained. The pricing shown is very approximate and conservative. Your prices may vary depending on your location and how friendly you are with you local salvage yards.
Use the following links for individual transmission pages: