M38A1 steering knuckle flange oil seal

giacomo · Post by **giacomo** » Tue Dec 06, 2022 3:59 pm

Hi all,
I'm replacing the steering knuckle flange oil seal and I kindly wanted to know if there is oil or grease inside the axle housing
in the latter case should it be inserted inside the hole in the axle housing ?
and in what quantity ?
thank you

Giacomo

Post by **wesk** » Tue Dec 06, 2022 5:22 pm

That depends on who last serviced it. Many folks follow the manual and a few go with their head. What is suppose to be in that knuckle is GAA (Gear Grease Automotive & Artillery) The joint is suppose to be topped of every 1000 miles thru the plug hole with GAA and anytime the wheel bearings are greases the knuckle should be disassembled, cleaned and repacked with GAA.

MIL-PRF-10924 GREASE, AUTOMOTIVE AND ARTILLERY
This specification covers one grade of a multi-purpose grease for lubrication of ground vehicles and equipment and is identified by Military Symbol GAA and NATO Code Number G-403.

MSDS Sheet: MIL-SPEC MIL-PRF-10924
chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://chemsol.com/wp-content/uploads/ ... -10924.pdf

Here's al the updates/revisions: https://chemsol.com/products/all-milita ... %20G%2D403.

giacomo · Post by **giacomo** » Wed Dec 07, 2022 1:48 am

Hi Wes thank you for reply
so to remove the old grease, must the knuckle be completely disassembled periodically ?
And how much should I put inside ?

Giacomo

Post by **wesk** » Wed Dec 07, 2022 10:15 am

Your owner's manual TM 9-8012 and the chassis manual TM 9-1804B describe the task in detail. You open the knuckle up but you do not dias-assemble the axle flex joint. You clean the cavity out and pack new grease in by hand to fill the cavity.

Post by **jake138** » Fri Dec 16, 2022 3:55 pm

Many people use John Deere Corn Head grease for their closed knuckles:

Amazon case of 6 tubes

These tubes will fit a standard grease gun and you probably won't have any issues shipping to Italy.

Brian Hainer aka "Metalshaper" on Youtube consulted with a lubricant company years ago to recreate the closed knuckle grease that he now sells. Watch the first view minutes of his Youtube video and I believe his email address is in the description, you can ask him if he'd ship to Italy:

Metalshaper Lubricants