Tranny or Gears

[Luke]

I have a question about my bronco. It's a pretty much bone stock 74 with a 2.5 lift. Anyways it has the factory 4.11 gears in it with a c4 tranny. On the freeway I am wanting another gear. I could put in taller gears but I don't wanna go there. I like the auto. So would my best bet be to do a tranny swap ? If so what kind.
Thanks
Luke

[Efibroncoman]

Re: Tranny or Gears

I've never heard of a Bronco coming with 4.11 gears. Most come with 3.50 gears in the axles. Either way, if you want to bring the engine rpm's down on the freeway you would need to go to a numerically lower gear set in the axles. But to answer your question, yes you can swap in a different transmission with an overdrive gear. A popular swap is the Ford AOD. However, that transmission is longer than the C4 and will require a new cross member, new drive shafts and possibly adapters to make everything fit. Wild horses as well as some other companies should have kits to help with the install if you don't want to scour the wrecking yards and get down and dirty. Another option is the NV3550 5 speed manual. It's a great transmission if you aren't planning big horsepower, large tires or off-road abuse. Pretty much any overdrive transmission either auto or manual will require major work but it has been done before and is possible.

[Luke]

Re: Tranny or Gears

I'll double check the gear ratio and report back. When my grandfather bought the bronco new he did have some stuff added from the dealer.
What am I looking for the axle code wise.
Luke

[BRONKEN]

Re: Tranny or Gears

I believe the six bangers came with 4:11 gears

[Luke]

Re: Tranny or Gears

Just checked the vin in the glove box a5 axle code (4.11's) Under the type on the vin tag it says u152.
on the tag on the rear end it says 4L11 9 697C
It's a factory v8 bronco.
Luke

[Bronco Brian]

Re: Tranny or Gears

I believe the six bangers came with 4:11 gears

Mine did and I think you could get 4.56 too, so why could you not get 4.10 in a V8.

[904Bronco]

Re: Tranny or Gears

For an auto tranny you have the AOD, early 90's being better than late 80's, or a 4R70W (from an Explorer V8, 98 to 01 being better) which is an electronically controlled AOD.

For an AOD you have to buy a kit from Advanced adapters that includes a new tailshaft housing and a new output shaft. You have to go into the trans to install.

For the 4R70W, you need to do the same as an AOD if it is a 2wd tranny. If you get a 4wd trans, you buy another adater from A/A that allows you to bolt up the D20 transfer case to it. You have to shorten the output shaft by a 1/2" or so and then change out the front of the D20. You do not have to tear into the trans. For both 4R70W you have to buy a stand alone controller so it will work.

Either way you go there is some work to do, not incuding driveshaft mods, trans support mods, some minor wiring, and gear shift linkage mods...

I have done an AOD in my former 75 and plan to do a 4R70W in a year or so in my 68...

[Luke]

Re: Tranny or Gears

Maybe the u152 has something to do with the gvw.
Glove box tag says max gvw lbs 4900 ???
But I am now sure it is a factory 4.11 v8 bronco.
I do not mind a stick shift conversion as long as I don't have do do a bunch of butchering.
Luke

[Luke]

Re: Tranny or Gears

Tag pics

[Henry66]

Re: Tranny or Gears

My 6 cyl. '66 U13 came with 411's. Top speed is about (maybe) 60 MPH.

I put many thousands of miles on an old ford 3 spd. OD. It was still strong when the 223 six lost a wrist pin. I could see why that would be a sweet set up in an EB.

[tortuga]

Re: Tranny or Gears

Lots of good info, but I didn't notice where you said what you wanted to use th e Bronco for - is it a trail rig, daily driver, somwhere in between...

What is your RPM at freeway speed now? Tire size? It all makes a difference.

[Luke]

Re: Tranny or Gears

Lots of good info, but I didn't notice where you said what you wanted to use th e Bronco for - is it a trail rig, daily driver, somwhere in between...

What is your RPM at freeway speed now? Tire size? It all makes a difference.

Sorry about that. Mainly a daily driver, Mild trails, cause I don't wanna beat my grandpas' rig. As it is now, about 60 miles an hour on the freeway is all she wants rpm wise cause of the gears, I have 30x 9.50's on it.

Luke

[CityHick]

Re: Tranny or Gears

Sweet rig!
To get your head spinning with gear combinations refer to the following site:

http://www.grimmjeeper.com/gears.html

This will allow you to virtually bolt together just about any imaginable combination of transmission/transfer case/axle gears. Even with doing mild trails, lower gears are always nice. 4.10 is a decent ratio especially with smaller tires.

But in short I think the AOD is your best option if you are to stick with an auto and want overdrive.

[DirtDonk]

Re: Tranny or Gears

Agree about the overdrive instead of changing diff gears. 4.11 is a sweet middle ground.

Factory optional 4.11's were actually quite common. Maybe not with the autos so much, but plenty around with manual transmissions.
3.50 was considered stock for the V8's, 4.11's for the 6's and an option for the 8's. 4.56 was an option through many years, at least with the 6's, but not sure you could still get them that low after a certain year.
And limited-slip diffs were options in both front and rear axles, again through most of the years. Fronts not so much, but they're out there.

Paul

[gddyap]

Re: Tranny or Gears

How often do you wheel it and do you ever plan on putting bigger tires on it? You could get a used 3.50 rear 3rd member pretty cheap and swap it out easily. Just don't put it in 4wd if you don't change gears in the front axle. Used gears for the front would be cheap too.