74 Four Wheel Drive Problems, Please Help

[utsports407]

I have 1974 Bronco. I have been using my four wheel drive with no problems. I tried using it this morning and it would not work. When engaging four wheel drive gearshifter you can hear it shifting from 2wd into 4wd but fourwheel drive will not work. The bronco has manual locking hubs and yes, i had them locked in. At first, I thought maybe something was froze up due to a low of 16 degrees. As I tried later in the day as the temperature reached 40 still would not work. Anyone had this type of problem? Any suggestions on how to diagnose?

All help appreciated

 

[Bully Bob]

Hi 407 & welcome..!

Hard to see how that's possible as the D-20 transf. case is pretty tough.

RU sure it's fully engaged.?

Did you try hi & Lo range 4wd.?

RU sure the hubs are functioning i.e. in good shape.?

By what means were you convinced it was working in the past..?

---- "Any suggestions on how to diagnose?" ----

Jack front wheels off the ground & lock the hubs....shift transfer into 4wd.....crawl under & try to rotate dr. shaft.

It shouldn't move other than the normal play.

(The rear dr. shaft will move that little bit with it as you wiggle back & forth)

However., the wheels will spin "by hand" in oposite directions (if it doesn't have "posi") & you'll see the axle u-joints spinning.

P.S. you can insp. the T-case shift rods fr. underneith with a good light. It's poss. the shifter is badly worn or broken

The "J" shifters do have problems.

 

[Broncoholics]

I'd say the hubs are not engaging. They could be filled with water and rusted in place like mine have done after it sits. Or its not dropping into 4x4 100% as the shift arms could need to be adjusted.

 

[utsports407]

It was one of my hubs. Evidently, four wheel drive will not engage if one hub is bad. One of my hubs was whistle clean but the other was full of muddy water. Can't figure out how the mud got into the hub when the other was so clean. The O-ring looked like it was in good shape on the bad hub. Any suggestions how so much mud entered the hub?

What happened is the morning I had to use pliers (could turn with hand before this morning) to twist hub into lock, it was 16 degrees. Evidently, all the mud/water had frozen and my forcing it to lock with pliers bend the teeth in the hub.

 

[Bully Bob]

That's what I thought..,

D-20's are pretty tough.

"Any suggestions how so much mud entered..."

If there's no obvious leak at the locking hub....check the rear wheel hub seal., it might have gotten into your bearings as well.

 

[utsports407]

I was talking to a vehicle educated friend today and he suggested wheel seal as well. I replaced axle few months ago and did not replace seal. I would consider myself beginner level when it comes to working on vehicles and never crossed my mind to replace seal as well. That was a big reason I wanted this vehicle is so I could learn to fix them. I had two friends with me yesterday, one of which is a jeep owner and he is always giving me a hard time about how jeeps will go places that broncos will not. Well, I dropped it into a huge mud hole, the vehicle got turned a little sideways and my tires are wore out with very little traction. There wasn't no other vehicles with us and we were a long was from anything. I could tell from there faces they new I was stuck. I backed up and floored it out of the hole. Buddy said he changed his mind about broncos. Got to love broncos!!!

 

[Bully Bob]

"Real jeeps are built., not bought."

I stuck my bud, in his rubicon, out here on a flat dirt trail..! The IH Scout behind him passed him then pulled him out.

These jeep guys hate my guts-n-livers..... If I don't go 1st., they won't go..!! (& I'm basically stock) B)

But yah., if you're going to play in "deep" water & mud... you'll soon be an expert mechanic.

Several seals on ea. front axle & a couple in the rear. Pinion seals as well.

Don't want that goo gett'n into the pumpkin.

 

[S_bolt19]

I had two friends with me yesterday, one of which is a jeep owner and he is always giving me a hard time about how jeeps will go places that broncos will not.

I have to laugh every time I hear that. A couple of facts about the age old Heep vs Bronco arguement...

#1 A Heep comes with weaker axles from the factory

#2 A Bronco is more nimble than any Heep out there with same type upgrades.

#3 A Bronco is also more stable than a Heep

Plane and simple, a Bronco has been tested several times by magazines through the years and in all tests, the EB has come out on top. EVERY TIME. The only time a Heep has ever eclipsed an EB is when it was built more than the Bronco was. There was a Popular Mechanics article from 1966 that did a comparison on a Heep, Scout & Bronco. I'll give you one guess who came out on top of that one. In the first year of production, the Bronco surpassed 20 years of Heep engineering. The king was crowned then and there ain't no-one been able to take it since.. /emoticons/[email protected] 2x" width="20" height="20" />