Warning please check

[Csm Davis]

I have seen this several times and have wanted to post it but have forgotten to do it, check the Axle flange bolts before you leave base. I have seen a lot of them loose and leaking but the most recent one caught me by surprise it is twenty five miles to the base and I was moving trucks to be cut up and I saw a leak but just made sure they were all at least snug, I have found many just loose and leaking but this was a lot closer to being bad than I knew. Truck ran so I drive it from my staging area to my lot AD when I got out oil was everywhere and All of the bolts had backed out half way or more! I know it is a lot of bolts but I would recommend anyone that is driving or towing a five ton to check these bolts and mark them to give you a quick check later.

 

[m16ty]

Both of the M939 trucks I have recovered had loose axle flange bolts.

 

[Beerslayer]

The last two m939 trucks we recovered had lots of loose axle flange bolts. Thanks to Steve for noticing and fixing!!!

He's a real champion truck guy.

 

[nf6x]

I just read this thread, and decided to grab a flashlight and 3/4" wrench and check that dripping hub on my M936A1 before bedtime. Sure enough, loose bolts all around! I still plan to service that hub before the truck goes anywhere, but maybe that will shut off the drip for the next week or three until that task gets to the top of my list.

Thanks!

 

[nf6x]

Hey, should I be worried about knowing off the top of my head exactly what size of wrench to grab to go fix my truck in the dark?

 

[quickfarms]

Is this a design flaw with these trucks, result of pulling the axles for towing or is it a maintenance issue?

 

[swbradley1]

Hey, should I be worried about knowing off the top of my head exactly what size of wrench to grab to go fix my truck in the dark?

Yes, you should be worried and seek help. I suggest logging on a buying another truck immediately.

 

[Csm Davis]

I believe it is a maintenance issue I am going to blue locktite mine and torque to spec. Then mark so I can keep a quick check on them.

 

[emmado22]

The root of the problem is just like the HMMWV halfshafts.. No one checks them until it is too late. Then it is the "trucks" fault, not the guy who is SUPPOSED to be doing the maintenance.

 

[Amram]

Too bad these bolts don't have the little holes in the head that would allow them to be lockwired. On the ship we keep bolts from backing out on us by lockwiring them together.

 

[Stretch44875]

It would be fun to safety wire all those bolts that close together. You can buy the bolts drilled, or drill them yourself. I used to be good at safety wire, looked purty when I was done.

I not so sure safety wire keeps them from backing out, or lets you know when one is loose by breaking the wire. Have to ask a wire expert. I've had the head of the bolts broke off and hanging by the wire.

 

[Jeff Nelson]

It would be fun to safety wire all those bolts that close together. You can buy the bolts drilled, or drill them yourself. I used to be good at safety wire, looked purty when I was done.

I not so sure safety wire keeps them from backing out, or lets you know when one is loose by breaking the wire. Have to ask a wire expert. I've had the head of the bolts broke off and hanging by the wire.

If the safety wire is done properly, it will stop the bolts from backing out (which is why it's done on ships and aircraft). It won't work if done improperly, nor will it fix bad threads or stripped bolts. A company called Aircraft Spruce is one place where you can buy MS bolts with safety wire holes. There are obviously others, but that one comes to mind.

 

[nf6x]

McMaster-Carr carries cap screws with drilled heads, but apparently not in grade 8.

I think it would be wise to check the lock washers under those cap screws, and replace any which aren't springy enough. Maybe the wedge-type Nord-lock washers that are popular on HMMWV halfshafts would also work well here? McMaster-Carr carries them.

 

[nf6x]

Yes, you should be worried and seek help. I suggest logging on a buying another truck immediately.

I almost fell for that, by the way. But I also figured out what to name my two most recent truck purchases.

M923: "Poor Impulse Control"

M936A1: "Hookers 'n' Blow"