Broke halfshaft in the field. Options please...

[Mike82ndABN]

Broke halfshaft in the field.

Broke the front left halfshaft at the outer cv joint. It's not flopping around so I threw it in high lock to drive on the dirt road back the pavement, at slow speed.

So so what are my options ?
Can I disconnect the front driveshaft and drive in H? Or will the transfer case just spin the front driveshaft hub?

If if that's the case can I still disconnect the front and then use HL or am I going to grenade the rear diff when cornering ? I think the rear diff can allow left to right difference but I know the transfer case won't allow front to rear slip, so I'm taking the front driveshaft off.

Help. Lol

 

[Mike82ndABN]

Ok so I pulled the left front half shaft, the 6 bolts on the rotor came out easy, then I pulled the broken end out the hub. I disconnected and removed the front driveshaft, had to drop the sway bar temporarily to remove it. So I'm rear-wheel drive now. The front drivetrain is all disconnected so there is nothing to spin around and mess things up. Now I'm hoping the rear diff allows left to right slip so I can corner in HL. I'm pretty sure it does allow slip since we need to use brake throttle modulation when a wheel gets up in the air and starts spinning.

 

[Mike82ndABN]

Made it back. Glad I brought tools today.

 

[DatGuyC]

Those look like the upgraded 10k shafts too. What were you doing when it broke?

 

[Mike82ndABN]

Yea I looked the other day and they were all 10k. We were playing in mud and trails with big puddles up to the doors, then climbing in clay pits. The outer CV boot had a tear on closer inspection afterwards, the grease inside was thin and milky. When it actually broke I was making a left turn on flat ground, it made some crunching noise and then just free revved.

I would have thought water getting in the boot would have just accelerated wear, I really don't know how long that tear was there and what this truck did in it's former life. Maybe it was operator error too, I could have had some rapid acceleration or deceleration that caused it to fail, wheel spin climbing in the pit and maybe it came down hard on that wheel and suddenly slowed it, breaking the bearing race/cage (not sure what that part is called). I have read that the rotating mass of the wheel can break the half shaft if you suddenly hit the brakes while a wheel is free spinning, or if a wheel in the air free spinning gets back on the ground and stops fast.

 

[TonkaT]

Glad you were able to get it going again. I can confirm that you have to drive in HL with the front drive shaft out. Otherwise the front driveshaft hub just spins, as you said. Mine's a rear-wheel drive only at the moment, too.

 

[Retiredwarhorses]

How did you secure the brake rotor once you removed it from the diff output flange?
in the hummer H1 community, they make a kit, it allows for the removal of the broken shaft, an insert like your broken end you left in the geared hub for the upper spur gear, shorter metric bolts to secure the brake rotor.
i would keep that broken piece you have for the geared hub as that's half the kit....you should not be able to use the 6 old metric bolts as they are to long and will contact the bolts that secure the diff on the diff hangar brackets...you could just grind down a set of 6 till they work to secure just the brake rotor without the inboard side of the halfshaft that is missing.
just use the old inboard shaft piece a as a gauge on how much you need to cut or grind off...it's not much, 1/8in maybe...

you don't need to remove your front drive shaft...just use 4 high on the tcase...

 

[Retiredwarhorses]

Here is the kit....Hs can fail in more then one way...you got lucky as you had that geared hub end...I like that as a better option...you just need these shorter bolts to complete your kit...

http://www.bluehummer.com/lihoplkit.html

 

[Mike82ndABN]

I honestly didn't think about the rotor being attached by those same 6 bolts, i failed to secure it, i just went outside and looked and it is still there but sure enough it is not attached to the diff output flange. I don't see any wear on the inside lip where the output flange would have been spinning against the rotor (without bolts to keep them attached to each other). Maybe because I removed the front drive shaft from the front diff, the driveshaft input flange just spun as the right wheel turned and the left output flange stayed stationary?

That kit looks great and would be worth every penny when something breaks. I felt pretty helpless out there.

 

[Mike82ndABN]

I finally got around to ordering a set of halfshafts this week. I want to replace the 6 bolts on the inside of each shaft, along with the lock washers. Are the Kascar bolts good to go? They don't look like they have the pre-applied locktite I have read about. I was also curious about the lockwasher, I have seen nord lock washers but I believe those are for the civ hummer, am i better sticking with the split type? Should I also be replacing the bolt or lock washer on the end of the shaft inside the hub?

Thanks.

 

[ClarkeF]

The last spec from AM General calls for the six bolts with factory lock title and the Nordlock washers. If you are reusing your bolts, use 272 Red (not the more common 271) loctite. The split-washers are not the way to go. If you order from Kascar, you will get the latest bolts with the pre-applied loctite.

 

[DLJIII]

Can you share the 10k half shaft part number with me please?
I have a 1987 m998 and I am brand new to this and I am overwhelmed and need to buy replacements for the rears.
Thank you

 

[Wire Fox]

Can you share the 10k half shaft part number with me please?
I have a 1987 m998 and I am brand new to this and I am overwhelmed and need to buy replacements for the rears.
Thank you

Get the -34P parts manual from the Technical Manual section at the top of this page. Be sure to read the introduction at the beginning of it that explains what the UOCs are (Use-On Code), which will tell you what code corresponds to what HMMWV (A13, H13, MMM, NNN, etc...). The A1 HMMWVs should be making use of the 10K shafts, so the part that lists a UOC of A13 [among others] should be the part number you need for your 10K half shafts. Do not buy 12K halfshafts unless you're prepared to also change other parts to accommodate those, as they are not cross-compatible as-is.

 

[DLJIII]

I am sorry but, I have no idea how to find the -34P tech man. I found the parts lists and manuals but I cant find the UOCs or the part number.
These manuals are speaking in a language I have seen for the first time 29 hours ago.
I found the halves and searched the part numbers and it just brings me back to tech manuals.
Work beat me up tonight and I am exhausted.

 

[Action]

The parts books show diagrams of almost every part on the HMMWV. Those part pics have little numbers with lines pointing to a part on that page. Go to the next page and find that number. Beside that number, you will see the NSN, part number, description, UOC, etc.

 

[Wire Fox]

I am sorry but, I have no idea how to find the -34P tech man. I found the parts lists and manuals but I cant find the UOCs or the part number.
These manuals are speaking in a language I have seen for the first time 29 hours ago.
I found the halves and searched the part numbers and it just brings me back to tech manuals.
Work beat me up tonight and I am exhausted.

At the top of this page (and every page on this site) is a link that says "Technical Manuals." I followed it to this thread: http://www.steelsoldiers.com/showthread.php?78861-TM-s-for-the-M998-series -34P was shorthand for TM 9-2320-280-34P, so sorry about that confusion. As well, to be fair, the manual number isn't written correctly in that linked thread, since -34 and -34P ARE different manuals. In the introduction section of the -34P, it explains how to actually use the manual. A lot of it won't apply to you (what unit level is authorized to do certain maintenance, who can order what parts and what tools, etc), but you'll see that list item 4 in the Introduction as "Explanation of Columns (Section IV)" which will literally tell you how to read the part of the manual you're most interested in. Section 5. "Special Information" explains the UOCs, what vehicle has what code, and some other useful information. Lastly, Section 6. "How to Locate Repair Parts" gives a good, simple process to help locate parts that you don't know the part number to.

Apply that new-found knowledge on finding some of the part numbers yourself. Give it a good try and if you still have trouble, I'll see if I can help you a bit more. Knowing how to read these properly will make you extremely self-sufficient and will greatly aid your ability to find cheaper parts, since you won't always have to turn to a dealer and say "I need a replacement xyz assembly...can you find that and order that for me?" and pay the highest dollar for it.