• Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!

d8k oil in finals from transmission

RedlineDrainage

Active Member
Joined
Mar 14, 2010
Messages
32
Location
NY
Occupation
drainage contractor
going to look at a d8k that is getting oil in the finals from the transmission, we are told that not alot is leaking by at the moment. We have had Cat tell us that alot of guys dont repair the issue and run them. Letting oil out of the finals and putting more in the trany from time to time. 3 mechanics have all said its the pinion seals and its a big job and bill to repair. Anyone had this issue and what'd you do.
 

Bob/Ont

Senior Member
Joined
Sep 18, 2012
Messages
1,605
Location
Ontario
They are most likely right, the rubber rings of the duo cone seals get hard.
It's a big job but worth doing if you plan to keep the tractor. Check out the whole back end when there will add value to the job.
Later Bob
 

nicky 68a

Senior Member
Joined
Apr 14, 2013
Messages
1,164
Location
england
the pinion seals can go brittle with old age and leak into the final or it can be debris from the bevel casing which may mean trouble.
in the past I have had quiet a few d6 and d8 tractors transfere and I have had no trouble with them.some of them leaked for years even though they were working 12hr shifts.When I first started out I was told to drain the final off every morning and replace the lost oil in the tranny.after a week of 6am starts getting covered in oil I gave up,kept the breathers clean and just ignored the problem.About 3 years later (3000hrs?) i had the final drive seals start to go which cant be ignored so after I finished the job we stripped it down to find the hub had started migrating about.the gears were all well worn out and so were the bearings but no failures.We rebuilt it and did the other side as a precaution.It wasn't blamed on the leaking top pinion seal.
An oil sample would put your mind at rest.
 
Top