Help - my wheel almost fell off

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Erik

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Erik
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Hey all. I have a 74 C20 with the 14-bolt full float rear end. I had a rear brake job done in November, and a couple months ago I was driving with a big load of lumber in the bed and the brakes and speedometer went haywire. I pulled over immediately and saw that the right-rear wheel had almost fallen off. If I had been on the freeway and it came off, it would have been bad news.
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A shade-tree mechanic friend - who is knowledgeable in general but hadn't worked on this type of rear end before - towed me to his house and fixed it after some trials and tribulations. He said it looks like whoever did the brake job forgot to put some clip back into the right hub assembly. I had a replacement hub handy, so he put that one on for me (the old one got chewed up).

He did not tear into the left wheel to see if the same mistake was made on that side. I've been driving it for a couple months now (probably 500 miles), checking the left wheel frequently, with no issues, no leaks, etc. My friend said he thinks if the clip was left out on the left too, I would have run into problems by now, so he suspects the mechanic didn't go as deep into the left wheel and never removed that clip. He said if it were him he would just keep an eye on it.

I'm not sure what clip he is referring to, and I have no experience with the hub, axle, etc. I want to assure that it's safe, especially since my kid rides with me in the truck sometimes. Any idea what clip he might be referring to and how I can check it? I do have a PDF of the complete service manual so can refer to the hub and drum assembly drawing. Or should I just let it go and keep an eye on it?
 

PrairieDrifter

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Umm well first we need to know what axle you actually have. A 14 bolt full float axle does not have c-clips, A 14 bolt semi float does have c-clips. If it is a semi float rear end and the c-clips were left out you wouldn't make it more than a mile if lucky, so I'm assuming it's a full float and I'm assuming whoever did the brake job either didn't properly set the wheel bearings up or forgot a locknut. Something in the hub assembly was wrong. Also you don't need to pull c-clips to do a brake job on a semi float, so leaning me even more to it's a full float axle and the brake job guy didn't have a clue
 

PrairieDrifter

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Unless axles seals were done at the same time.
 

86 SCOTTSDALE

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The clip he is referring to is probably the one that prevents the wheel bearing nut from turning once it is set. Full floating axles have spindles and two bearings on each side. I had a ram 2500 with a dana 70 rear end that used clips to keep the wheel bearing nut from turning.
 

86 SCOTTSDALE

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You can unbolt the axle shaft from the hub without removing the wheel, just set parking brake or block the wheel, slide out the shaft and you should be able to see the nut and a clip of some kind keeping it from turning. There will be some oil that will spill out.
 

PrairieDrifter

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A c-clip and an axle locknut are two different things.
 

Craig 85

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Termite_Delight

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There is a special tool to remove and install the locking nuts and must be torqued to spec.
 

Erik

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Thanks. My axle is definitely a full float, and he was not referring to the c-clip, as I understand that is in the differential on a semi-float. My guess is he didn't know what the hell he was doing and didn't re-install the locknut or locknut retainer. Here is the diagram from the service manual. It looks like #3 might be the lock ring Craig 85 is referring to and #4 may be a clip to hold the ring in place. If the guy forgot the retainer, i guess that ring could have worked its way loose? Sounds like I should pull the axle and take a look.
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Erik

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If I pull the axle, will I be able to tell just by looking at it whether the locking components are in there, or will I need to take them out to verify? Also, how do I replace the gear oil that spills out? Thanks


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K201979

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If I pull the axle, will I be able to tell just by looking at it whether the locking components are in there, or will I need to take them out to verify? Also, how do I replace the gear oil that spills out? Thanks


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If you pull the axle, you should be able to see the tab from the locking washer bent around to the front, in one of the indentions, as it shows in the picture in Craigs post. This tab might have been your problem. It could have broken off due to repeatedly bending it back and forth. To refill, there should be a plug on the passenger side, towards the front of the diff. Itll probly have a square hole that your (3/8ths drive i think) ratchet will fit in or a square head.
 

Erik

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Thanks. The tab breaking could have been the problem. I had a couple mechanics work on the brakes that didn’t turn out so well. I’ve had a hard time finding someone around here (Charlotte NC) who is willing or able to work on an old truck. I’m gonna pull the axle and see what I find.


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K201979

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Thanks. The tab breaking could have been the problem. I had a couple mechanics work on the brakes that didn’t turn out so well. I’ve had a hard time finding someone around here (Charlotte NC) who is willing or able to work on an old truck. I’m gonna pull the axle and see what I find.


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Yup, thats why i work on my own stuff. If you dont know it yet, its all out there on the old interwebs. :waytogo:
 

Erik

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C20
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I hear ya. It can be intimidating though trying to figure all this stuff out. Thanks for the advice.


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