M812 5 ton steering knuckle boot question..

[Andydieselpower]

I'm in the process of replacing my steering knuckle boot. After taking off the old boot and the boot/knuckle protector plate on the front of the axle I put some grease in the bottom grease zerk under the axle to see where exactly the grease from this zerk goes into the assy. At first it just squirted grease out of the flange where the grease zerk is held onto the bottom of the axle. I then reinstalled and tightened my two bolts that held on the front of the protector plate and then retried putting in grease only to have it squirt out of the sides of the flange again. Can I take this bottom plate off? I notice only two more bolts holding it on. Is there anything that is going to fall out or being held in that is held by this plate? I just want to clean the plate and reinstall so that the grease goes into the assy. Before the boot repair the zerk took grease fine and didn't purge out.
Thanks,
Andy

 

[acetomatoco]

The detailed pix in your manuals will answer your question...

 

[Andydieselpower]

worthwhile respones?

My manuals & cd which I do own will be located at my office over the weekend so I won't be able to access them to look up the repair. I'm in the middle of this project and would like to get this completed. Anyone with a useful response that knows this axle setup would be appreciated.

I get a kick out of the manual answer. If the manuals have all the answers why do you post on this website?

Thanks,
Andy

 

[acetomatoco]

RE: worthwhile respones?

Cuz your manuals are not with you...if you read up on the repair first you will not have to post, but I understand your angst. The trucks are fun and should not cause you hypertension, nor should you take umbrage at those who try to advise you. The public forum is for people to be praised or spanked, and of course the posts are only as valid as the post and the interpretation of that post by the plethora of recipients.

 

[cranetruck]

This may help answer your question and/or ask another.

 

[m139h2otruck]

When I read the manual, I understood that the two plugs were also for forcing grease into the CV joint as much as for checking the level. When I just did the joints on the front of the tractor, I greased the king pin/trunnion fittings with 3 or 4 shots and then took out the two plugs and put about a half a tube (a quarter tube per hole) into the two holes in each CV joint. This way the grease is in the actual CV joint itself, rather than on the front (outside) of the half shaft behind the stub axle. If you look at a blow-up of the joint/axle you will see what I mean.

 

[Cdub]

I also had wondered about those holes or plugs in the CV part of the axle housing. The LO shows a number with an arrow but with no explaintion of what they are or what they are used for...??

I think someone had told me I could put a gresse fitting in there...??

I'll have to take a closer look again at the front axle and see if those plugs are in place and just filled with dirt and painted over. I'll do a much better cleaning this time since I know to look for a hex plug.

He's the LO for a M939 five ton. It doesn't say much about them or give any details. I'll have to go back to the -20 and take another closer look.

 

[Cdub]

This may help answer your question and/or ask another.

Bjorn, Thanks so much for posting that bulliten......it explains what they are used for and why. I still haven't seen anything in the manuals yet about it....strange...??

Cheers,

C'dub

 

[jwaller]

if you grease the top of bottom zerk you are forcing grease thru the kingpin bushings. the stock ones have lube channels built into them for this purpose.

If they have been replaced then they no longer have the grease channels and this will be much more difficult.

I have spoken at length with several of the major rebuilders about this issue. they all told me they dont care 1 bit about getting a ton of grease into the knuckle. The cv doesnt require grease.

they are sealed units.
If you get greas to touch them then soon as you get 5-10 mph the rotaition of siad joint is going to sling off that grease.

Hence they simply say to run them nearly dry. there is no need to pack the knuckles with endless amounts of grease.

 

[SilentSpeedy]

Today I just noticed a rip in my knuckle boot of about an inch length. This article is very helpful to me. Just like the initial poster I can not find any info in my manuals.

 

[SilentSpeedy]

knuckle boot change

I have also a problem with a knuckle boot, and am wondering, do I need special tools to change that boot or is it doable by hand?

 

[73m819]

by hand,
I had trouble getting the wire ring on and staying on to tighten, I took a needle and heavy thread, then sewed the boot to the wire every 2", a bit of grease at the grove, the wire boot edge slipped in with a bit of pressure. just make sure you have everything indexed first, before I slipped the sewed boot on, I put 2 screw at 3/9 o'clock through the boot to the knuckle, this kept everything indexed, also make sure the outer retaining ring is flat and not distorted by previous over tighting