Automatic transmission upgrade

[tom9961]

I have a stock 72 and was wanting to upgrade to a automatic trans. Does anyone know what the total cast would be to upgrade to one of the overdrive transmission I read about on this forum.

 

[sykanr0ng]

Many variables to consider:

4R70W or AOD transmission?

Using the carb engine (or an aftermarket TBI) or swapping in a factory EFI?

Swapping in an Explorer 5.0 and 4R70W may cost you less than just the 4R70W and using an aftermarket controller, for example.

 

[tom9961]

Thanks for the info sykanr0ng, Any idea what this would cost all the modifications that I would have to make. Drive line, transfer case adaptor and etc.

 

[sykanr0ng]

It has been discussed a bit lately, here are a couple of recent threads with some cost figures:

4r70w swap questions

4r70w swap

If you don't want to go EFI an AOD transmission may be an easier swap, though not as good a transmission (the 4R70W is an improved and computer controlled AOD)

 

[Broncobowsher]

Depending on axle gearing you may need to add in regearing the axles so the overdrive will be useful.

Doing the work yourself or paying to have it done?

 

[Crawdad]

You will need an adapter to the transfer case as well.

 

[AZ69EB]

Ask yourself how you are going to use your bronco first. Going auto is great for some and others just want an overdrive because it's cool. Light trail and street 33" tires, 3.50 or 3.73 gears, and C4 has been the ticket for many since early 70's. You can even go 4.11's if you wheel it a little harder with lockers. It's the cheapest way to go.
Going overdrive can get expensive quick to make your bronco work across a broad speed range. I have about $3k for 4R70W rebuilt, new torque converter, coolers, and US Shift controler. I already had ZF to D20 adapter. I still need to correct driveshaft lengths. But, I also already have 4.88 gears and going 408W. So it makes sense to spend the cash now for how I want to use the bronco in the future. According to my wife, " I have extra space between the ears ." But, that's a different story. ��

 

[AZ69EB]

You can also help another bronco brother out by purchasing their complete used C4 if the are making the switch to an overdrive. So, check out our used parts for sale section, CL, and your local bronco brothers for a great deal.

 

[Broncos n' VWs]

I'm sitting here doing some quick addition in my head on what I know I shelled out for parts when I did my 4R70W swap. Here is what I did and approximate $$ paid (Keep in mind that I did this swap close to 10 years ago):

1. 4R70W from LKQ, used 2000 Explorer/Mountaineer - $300
2. Advance Adapter intermediate housing and replacement output shaft $550-600
3. rebuild and output shaft install -$600 (I have a transmission buddy at AAMCO)
4. Mercon fluid and filter - $70
5. Baumann TCS (now US Shift Quick 4) - $600
6. new drivelines - $400
7. exhaust rework - $150
8. new flexplate - $50?
9. starter motor (used) $20
10. Misc wiring and connectors $20

Now... I have Ford EFI and a RJM harness with the TCS connector which makes the TCS harness plug-n-play. I already had 4.56 gears, 35 inch tires and I did all my own installation work, except the rebuild. I modified my existing cross member (ugly as hell) and used my existing column shift with a cobbled together bell crank. It works. I feel like I'm still forgetting something...