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AOD to manual

Mr. Mikes 74

Jr. Member
Joined
Oct 20, 2010
Messages
56
Loc.
Long Island
Im building a 74 and Ive been throwing the idea around of taking my AOD transmission out and putting a 5 speed in. Looking for your thoughts on this. The previous owner took the original 302 and 3speed out and put in a 89 302 and an AOD. I like the idea of having a manual because the bronco is a toy to me. I still have to mate the AOD to the d20 tcase and im installing a 5.5 inch SL. What mods need to be done to the floor? I have a hole in the floor for the shifter the PO put in aith the AOD. I still need to cut a whole for the tcase shifters too. What transmissions should I look for? Any cons to doing this? I do plan to rebuild the original 302 and put that back in the truck. Will the new 5 speed bell housing fit the original 302 also? or the orignal and new 302 have different bell housing bolt holes? Any and all input would be greatly appreciated.
 
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Trigger

Sr. Member
Joined
May 20, 2002
Messages
620
I swapped out an AOD for a ZF as you can get a ZF from an 88-94 F250 that has a small block. The bell housing is integral and matches up to the 302. You would need an adapter to go to the D20 tcase. A new crossmember is needed, new drivelines, exhaust work, tcase shifters (twin stick install, I used rod ends and some mods to my twin stick, it's never shifted so good. I am happy with my swap, a stick just feels right in a Bronco. The 5.72 granny gear is nice for crawling around the woods. All in all it's cheaper than the other options, at least for my setup. I got mine for $250 at a local wrecking yard which included the tranny, master cylinder, flywheel, clutch. I ended up replacing some stuff but it was under $1100 or so. Their is a great article under tech that goes over all the most popular manual options.
 

bsquared

Contributor
Sr. Member
Joined
Dec 4, 2010
Messages
960
Do you have a 5 speed already picked out?

I went with the ZF - S542 5 speed out of an 85 F250. (I think) Plenty of info on here about that install. Main point is you'll need at least a 1" to 2" body lift to keep from cutting out too much of your tunnel. Here's a couple of pics of where I cut. Went a bit too far on the pass side. If you go with the NP205 xsfer case, you'll have to notch the ZF rear flange for the shift pins and make some kind of brace to suppport the weight. I welded a bolt to the frame for it. Good luck!
 

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Mr. Mikes 74

Jr. Member
Joined
Oct 20, 2010
Messages
56
Loc.
Long Island
Crawdad, theres nothing wrong that i know of with the AOD. Im going to have a friend look at the and beef it up if necessary when I adapt the d20 to it.

I dont really have a transmission picked out yet, I was looking at TBP and JBG and BC broncos kits. Toms and graveyard like the nv4500 and BC likes the zf. I dont really see the difference between the transmissions. As far as the transfercase goes I dont have shifters for it, was just planning on buying the t or j style depending on what route I go. Thanks for the info so far.
 

Trigger

Sr. Member
Joined
May 20, 2002
Messages
620
The main difference between all the manual options is price. The 4500 is very expensive. I think it will just come down to how much you want to spend. I went with the ZF mainly because it was the cheapest option.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,833
Do you want the 5-speed to be like a car 5-speed or a truck 5-speed?
The NV3550 makes for a nice driver 5-speed.
The ZF makes for an easy truck 5-speed.
The usual transfer case options exist. Any of the aftermarket stuff, D20, ZF can take the NP205. Just can't run any of the modern factory transfer cases, too wide to fit in the frame.

Once you know what you want then the other parts needed can be picked out. You will need a flywheel and starter. The clutch pieces will vary. Holes in the floor will vary as well.
 

blubuckaroo

Grease Monkey
Joined
Jun 11, 2007
Messages
11,795
Loc.
Ridgefield WA
One advantage of the NV3550 is that the overdrive ratio isn't as extreme as that of the Ford overdrive automatic transmissions. I am able to use 4.11 gears with my NV3550 but would probably need 4.56 gears with an AOD or 4R70W.
 
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Mr. Mikes 74

Jr. Member
Joined
Oct 20, 2010
Messages
56
Loc.
Long Island
Broncobowsher: Im not to concerned about the truck shifting like a car or a truck. Im not looking to bang gears going down the road. Im only considering this swap because I need to mate the AOD to the D20 already and im not really sure how good the tranny is as we speak. THe truck will be mainly used on road and the beach and occasional snow. Im not going to rock crawl with the truck or anything serious like that. Im not going to get rid of the D20 either. Im lanning on running somewhere around a 37 inch tire too. I know I want and over drive tho so I dont scream down the highway.

blubuckaroo, The whole gearing aspect is chinese to me. I plan on running a 37 inch tire and I will be putting some sort of locker in the rear either limited slip or air cross that bridge when the time comes. As fore gears im not sure whats in the truck as we speak but I know I will probably have to change that too. Im looking for something that will be good on the street doing 65MPH and not scream and the 5 speed just seems like it would be fun to drive. Just trying to weigh my options out right now.

Thanks for the input so far
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,833
Sounds like you want it to drive like a car, not a one ton truck. So that will put you into the NV3550 range. That is the move fun on the street option. But lacks deep gears that it sounds like you don't care about anyway.

The truck 5-speeds drive like a 1-ton truck because that is what you get them out of. Wide gear ratio spreads. They are for working, but that also means they take power and abuse better. Basicly the old 3-speed with a granny and an overdrive.
 
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Mr. Mikes 74

Jr. Member
Joined
Oct 20, 2010
Messages
56
Loc.
Long Island
I think im leaning more towards the NV3550 but Im also second guessing the NV4500. I will have 37s on the truck and the sand on the beaches here in Long Island is soft and tires spin and people get stuck. Im thinking the 4500 will handle the abuse of pulling a friend out and getting myself un stuck. Correct me if im wrong. The NV3550 is out of wranglers and libertys 2000 on? and the NV4500 is out of Ram pick ups non diesel? Im thinking of going to the junk yard and seeing if i can get one there and then just have to buy the swap kit from one of the vendors. Is there anything i should look for? Are they all the same?

Happy Holidays guys
 

John Marinan

Contributor
Sr. Member
Joined
Aug 9, 2009
Messages
680
Loc.
Durango CO.
The NV 3550 is an out of production transmission. They still make the AX 15. the new model is much better than the 3550. It is the manual transmission offered in the ICON Bronco.
 

John Marinan

Contributor
Sr. Member
Joined
Aug 9, 2009
Messages
680
Loc.
Durango CO.
These are new transmissions still in production. They are the same size as the NV 3550, use the same add on twin sticks etc. Check Roclwell Standard Gear, Novak Conversions, and Advance Adapters. Advance has the adapters that you need. They we're out of the transmissions when I did mine so I bought the transmisssion from RSG and the adapter parts from Advance. RSG calls them the terminator. I think novak throws in a Hurst shifter.
 

Pa PITT

Contributor
Bronco Guru
Joined
Jul 15, 2005
Messages
11,252
Loc.
Stephenville TEXAS
I guess I'm the only one here that's going to say the NV4500 is the best. But granted it's best in only my opinion.. I worked for a Dodge truck dealership and we handled a lot of 4500 repairs .. But after you saw what they had been doing for work you'd understand them also needing repairs. Now yes 95% of ours were the Diesel tr's & I believe that the only difference is the main shaft stronger on the diesel. Because you can buy a shaft to swap a gas 4500 to use on the diesel swaps.
... Now all that being said .. how much stronger trans do you need in a Bronco that is only . cruising and then pulling it's self up a mountain.
...
...... The real problem will most likely be your Dana 20.
 

Fireball05

Bronco Guru
Joined
Oct 7, 2012
Messages
1,822
On Advance website it lists a rebuilt 3550 at the same price as a new AX 15. Why wouldn't one get the new Ax 15?

I've read a lot on here about the 3550s, but haven't heard much about the 15s.

Any other info would be great!
 

John Marinan

Contributor
Sr. Member
Joined
Aug 9, 2009
Messages
680
Loc.
Durango CO.
On Advance website it lists a rebuilt 3550 at the same price as a new AX 15. Why wouldn't one get the new Ax 15?

I've read a lot on here about the 3550s, but haven't heard much about the 15s.

Any other info would be great!

Check the Novak and RSG Terminator sites, they are covered pretty well.
 
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