Left rear axle came out

[jason_marshall1]

Background: 9" rear end, 28 spline, small bearing, 27.25" length (LH) driven on the road with minor off road usage. The bearings and seals were replaced two years ago.

Issue: The axle slid out of the housing, away from the center about 9/16" (I didn't actually measure), when I removed the axle the last 1/8" of the splines are rounded. I assume this happened as the axle was idle and the carrier was turning under engine power. My son was driving and said it would not move after stopping at a stop sign.

Diagnosis: The axle retainer plate is in good shape and all four nuts were tight. I removed the carrier to look for metal, debris,damage etc. The carrier is in great shape and no damage can be seen on the spool splines.

Sooo, anyone else experienced the bearing coming loose from the axle? I pressed the bearing back into place and it seemed very tight. My press groaned and the bearing popped several times as it moved down the axle shaft. Before I throw money at new parts, I thought I'd ask. I tried to search for similar issues, apologies if this is a duplicate thread.

 

[DirtDonk]

Wow, bad news jason! We see it happen with old bearings now and then, which is why it's high on our list of must-do things when you get a Bronco. But don't remember ever hearing of new-ish bearings letting go.

Could the threads have stripped out of the housing, letting the bolts themselves release? I'm guessing you would have seen that, or at least noted it when trying to torque the retainer back down.
And since you say you pressed it back on anyway, it's sounding a pretty sure thing that the bearing and it's retaining collar slipped.

Before you pressed it back on, did you note how it looked? Shiny shaft showing? Any unusual marks on the shaft?
How powerful is your press? These things are pressed on pretty tight, but I would imagine even a normal home/shop press could do it. The fact that it groaned a bit should say it's tight, but wondering if your press is not a good indicator if it's a smaller one.

What size tires you using?

Paul

 

[garberz]

Wow, I wouldn’t hesitate to buy a set of axles for it. A few hundred dollars is worth it to keep that from happening again.

https://www.wildhorses4x4.com/product/Heavy_Duty_Rear_Axle_6675yr_Sm_Bearing_10in_Drum_Left/bronco_rear_axle

Mark

 

[Rustytruck]

If you have a problem that is serious like this and you don't change the suspect parts you are likely to have tge same problem again with a more serious out come. Dont take chances spitting out an axle. Loosing an axle at speed is dangerious to life, limb, and may cost you more than just a roll over.

 

[jason_marshall1]

Wow, bad news jason! We see it happen with old bearings now and then, which is why it's high on our list of must-do things when you get a Bronco. But don't remember ever hearing of new-ish bearings letting go.

Could the threads have stripped out of the housing, letting the bolts themselves release? I'm guessing you would have seen that, or at least noted it when trying to torque the retainer back down.
And since you say you pressed it back on anyway, it's sounding a pretty sure thing that the bearing and it's retaining collar slipped.

Before you pressed it back on, did you note how it looked? Shiny shaft showing? Any unusual marks on the shaft?
How powerful is your press? These things are pressed on pretty tight, but I would imagine even a normal home/shop press could do it. The fact that it groaned a bit should say it's tight, but wondering if your press is not a good indicator if it's a smaller one.

What size tires you using?

Paul

The press is 20 ton. I use wood to press against the bearing races and the wood was indented about 1/8" when finished. I guess I'll get the chance to see how it reacts with new axles and bearings. The axle looked fine, no discoloration or heat marks from prior abuse that I could tell. It was dirty, I would call it road grime and brake dust (drum brakes). Evidence it has been creeping out over time I suppose.

Cheers-

 

[Joe473]

The press is 20 ton. I use wood to press against the bearing races and the wood was indented about 1/8" when finished. I guess I'll get the chance to see how it reacts with new axles and bearings. The axle looked fine, no discoloration or heat marks from prior abuse that I could tell. It was dirty, I would call it road grime and brake dust (drum brakes). Evidence it has been creeping out over time I suppose.

Cheers-

Replace the axle. Some shops press bearings on and off. I prefer cutting them off and pressing on. Pressing on and off a few times could reduce the interference fit of axle and cause issues.

What kind if wood? If pine or fir thats not much pressure. If a hardwood I might feel better about it. Things like this make me seriously consider full floating axle conversion.

Sent from my SM-G960U using Tapatalk

 

[blubuckaroo]

You said nothing about the bearing retainer ring.
You did press new ones on to the axles when you replaced the bearings last time, didn't you?
Without the retainer, the axle will certainly slide out under normal use.

 

[Apogee]

Like blubuckaroo said, when you pressed the bearing back onto the axle, it sounds like you were pushing on the bearing, not the bearing retainer collar. In general, the bearing is a light press fit to the axle and the retainer collar is the heavy press-fit and is what primarily retains the bearing on the axle. On worn axles that have had a lot of bearings on and off over the years, and/or poor technique for bearing removal, I've seen collars walk off, but not on axles in relatively decent shape.

 

[B RON CO]

Hi, if the retainer ring was left off the one side you need to check the other side right away.
Good luck

 

[jason_marshall1]

I took a step away from the near disaster for a day or so. I origially forgot to look closely at the retainer rings, the axle is 1.375 OD and the bad retainer is 1.378 ID. The name on the bearing is Tapan, since the retainer and bearing came together I assume the same brand for both. The right side (good) retainer is 1.372 after pressed off the shaft. The new timken retainers are 1.372. Waiting for new axles, but consider the issue resolved for now.

I was bit by crappy parts, the old retainer is still shiny with no discoloration or heat indications. I assume it stretched; while I wait for the axles I will put the bad one on the lathe to see if it is still round. Maybe there is one bad spot and it's now egg shaped..

Sent from my SM-G930V using Tapatalk

 

[nvrstuk]

Your son was LUCKY! I say this because of the number of rolled and totalled Broncos that have been bought by friends of mine in our Valley...seriously, I'm NOT exaggerating. Been driving Broncos since 1970. One buddy (best friend) bought 6 totalled Broncos in 2 years-in our little Valley with 30,000 people. Bought my Bronco in '76 and had serious issues with axles and brgs walking out 8 years later...new ones with new axles... those were 18 year old axles...not 40+ year ones like everyone has now.

To prevent this I built a custom rear 9" housing with 14 bolt hubs that are FF to eliminate 9" axles walking out since it happened 3 times to us on different vacations.

Gotta remember, most of the Broncos are driving around on 40+ year old probably slightly bent housings, OLD axles, being repaired by shops that probably press one axle brg on a year compared to the old days of doing it weekly or monthly (practice makes better).


Anyway, don't take this lightly...most common result of losing an axle while cruising down the highway is rolling over...

 

[DirtDonk]

What they all said. Glad you came over to the forum when you had your issue. And even more glad it was just "an issue" and not a catastrophe that it could have been.

This is why when new owners ask what should be done/checked, we are always on about verifying that the rear wheel bearings have been replaced at some point in their lives.
Back when they were only 5, 10, or even 15 years old, only mileage mattered. But now, with 40+ years on the YOUNGEST Broncos(!) it's age as well as mileage.

Sounds like you're all over it though, with getting measurements, then correct bearings and collars, and (it sounds like?) buying new axle shafts as well.
Now it'll be good for the next 25 years or 100k miles. Whichever comes first!

Oh, but if your Bronco gets beat on off road regularly, or ever ends up getting into a rear-end fracas with another vehicle, don't hesitate to change them out early next time either.
Or heck, with the small bearing model, if you have built yourself a heavy Bronco (all the goodies and then some) and travel heavy on any off-road excursions or long road trips (in case this is that type of Bronco?) then that's a good reason to maybe do early retirement for old bearings as well.
Something like 75k miles, or 15 years maybe? Just throwing out numbers here. Most troubles occur after 100k miles, but as they say... "Your mileage may vary"!

Good luck.

Paul

 

[gick70]

Stop and listen for any new noise or rattle,check it out. Don,t take a long trip until you have the noise figured out ,today with the quality of parts today the longevity of yesterday is over!

 

[timfoster]

Is there a way to check the axle to see if it has become loose? Example, jacking up and pulling/pushing on the wheel for excess movement. This could be a good practice every 6 months or so.

 

[Bronco4x4]

Rear disks can help hold things together as a backstop. I agree with frequent inspections with parts being made overseas.