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4r70w Swap

SSDDBRONCO

Bronco Guru
Joined
Nov 12, 2009
Messages
2,170
Loc.
Los Angeles
Yes i kno the search feature is great ;D but i need some better info on how to swap and replace my c4 and the right transmission that i need. Right now i have a 302 and i am going to keep it until it fails, but in the meantime i want to bolt up the 4r70w to my 302. I have quite a few questions.

1. What is the best year to pull a 4r70w from?

2. Does it have to be from a 4x4? Why? (From what i read it does not have to)

3. What should i look at to make sure it's the transmission that i need.

4. Do i need a body lift?

5. Is it better to use my D20 tc or just replace it with the np205 tc and save money from the adapter.

6. What about all those other little parts like flex plate, crossmember, and etc.

7. In the future the 4r70w will bolt up to a 351 as well right? Just making sure.

I know i need the Baumann as well.
That's all i can think of right now. If there is any other info that i should know please let me know.

Thanks
Kev

Update
Look at post # 15.
 
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G's Baja Bronco

Bronco Guru
Joined
Aug 7, 2010
Messages
1,362
Loc.
Sunny SO CAL
1. What is the best year to pull a 4r70w from? I believe the newer is the better, better parts, as ford learned what broke, they upgraded it. the v6's fit small block fords (302, 351w).

2. Does it have to be from a 4x4? Why? (From what i read it does not have to)
only if you want to go with a NO 205 and save the money on the adapter, I paid $150 for the NP205. and you do NOT have to open the transmission to install the adapter.

3. What should i look at to make sure it's the transmission that i need.

4. Do i need a body lift?
I had to run a 2" BL to clear my AOD (w 4R70W internals).

5. Is it better to use my D20 tc or just replace it with the np205 tc and save money from the adapter.
that is what I did. you will need a custom cross member and a side mount for the NP205, I fabed both of them. Check out my build for pictures.

6. What about all those other little parts like flex plate, crossmember, and etc.
The Transfer case to Trans adapter holds up both of them. Flex plate should bolt up to the Torque converter.

7. In the future the 4r70w will bolt up to a 351 as well right? Just making sure.
Yes.
 

EricLar80

Bronco Guru
Joined
Jun 14, 2001
Messages
2,170
Yes i kno the search feature is great ;D but i need some better info on how to swap and replace my c4 and the right transmission that i need. Right now i have a 302 and i am going to keep it until it fails, but in the meantime i want to bolt up the 4r70w to my 302. I have quite a few questions.

1. What is the best year to pull a 4r70w from?

2. Does it have to be from a 4x4? Why? (From what i read it does not have to)

3. What should i look at to make sure it's the transmission that i need.

4. Do i need a body lift?

5. Is it better to use my D20 tc or just replace it with the np205 tc and save money from the adapter.

6. What about all those other little parts like flex plate, crossmember, and etc.

7. In the future the 4r70w will bolt up to a 351 as well right? Just making sure.

I know i need the Baumann as well.
That's all i can think of right now. If there is any other info that i should know please let me know.

Thanks
Kev

Those all look like questions that have been answered in a lot of detail on this site before... The search feature is great!

Eric
 

broncokak

Bronco Guru
Joined
Jun 13, 2006
Messages
3,964
I'm collecting parts for this swap right now. I have the 4R70W and the Baumann controller is on the way.

Here is what I have leaned or been told as I have collected parts...

1) I was told by Kevin at Baumann to find a 1998 or newer. They have the updates already in them from Ford. Older ones will work fine, they just don't have the updates yet.
2) 4x4 would be best. If you get one from a car you'll need to get a 4x4 output shaft and swap them.
3) I'm not sure how to tell them apart other than mine has 3 electrical connections on it. One on the valve body, one on the sifting linkage and a speed sensor connection as well.
4) I have a buddy that has one in his EB with no body lift so I think it will fit.
5) That is up to you. I'll be using my D20. I have a ZF now and that adapter will work with the 4R70W.
6) I'm working on this little stuff now.
7) Yes, 302/5.0L and the 531 have the same bell housing bolt pattern.

Hope that helps. It's a learning process for sure.
 

69BroncoDad

Sr. Member
Joined
Jul 6, 2009
Messages
460
Loc.
Rutland
not to highjack your thread...I ordered my flex plate and it came in 157 tooth...back and forth with the sales guy he wasn't sure what one to get now..I have a 69 302 block..4R70W trans from a 2000 exploder...anyone got a part number or specific vehicle to order from..?? Thanks
 
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SSDDBRONCO

SSDDBRONCO

Bronco Guru
Joined
Nov 12, 2009
Messages
2,170
Loc.
Los Angeles
Thanks for all the responses. What transfer case is better the d20 or the np205? Should i consider buying the adapter or just go with the np205.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,821
If you get a 4WD transmission and cheap out on the transfer case, the 205.
The 205 is stupid strong. But the low range totally sucks. You will have a nice wide ratio transmission but the transfer case will be so narrow in the gearing it just won't be that usable. But if you rarely or never use low range it will be perfect. Low range would probably be high enough that you could actually use it on the highway.

I had a 3.15:1 tera-low gear set in the D20 behind the 4R70W in the last Bronco. That was about as perfect as you could ask for. overdrive low range was about the same as 1st gear high range. I had every gear I needed between crawl and highway. Best part was no overlap (remember the old 10-speed when 3 gears on the high side were the same as 3 gears on the low side, so it was really only a 7-speed?)

The stock D20 isn't 3.15:1 but it is better suited then the 205. My pick would be the original D20
 
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SSDDBRONCO

SSDDBRONCO

Bronco Guru
Joined
Nov 12, 2009
Messages
2,170
Loc.
Los Angeles
Instead of the adapter for the D20, you could spend a bit more $ and buy the NWF Black box-i and use that as your adapter, then you would have a 4 speed T case for just a bit over a grand. When else would you have that opportunity?

http://classicbroncos.com/forums/showthread.php?t=173399

never heard of these guys%). seems like it would be a good thing to invest into, but an extra grand is quite a lot of money. i will think about this maybe down the road as im collecting parts i will have the money lying around;D but since u mentioned this if i use the black box-i can i get the transmission from a 2 wheel drive or would u prefer to just get the 4x4 version.

What vehicle would be the best donor for a 4r70w 4x4 or 2 wheel drive
 

Amac70

ME
Joined
Mar 27, 2002
Messages
3,269
two bolt starter. that tranny won't work its for a mod motor 3 bolt starter. I paid 300 for mine i think that is a good average price.
 
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SSDDBRONCO

SSDDBRONCO

Bronco Guru
Joined
Nov 12, 2009
Messages
2,170
Loc.
Los Angeles
ok so i called many junkyard out in socal and seems like most have them for around 400-650 bucks 90 day warranted are those good prices? coming out anywhere from a 1998-2000 5.0 4x4 with around 70,xxx miles and above. Should i plan on rebuilding them or just leave them as is? If you guys have anyone u can recommend me to that would be great.

Thanks
Kev
 
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Terkish

Sr. Member
Joined
Feb 22, 2008
Messages
414
that seems like a good price range to me. I am in the same process my self. I called around here in Ut and the cheapest i found was $860 and up to $1300. Then i got luck at a pull it your self yard and picked one up for $250.
 
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