Recently moved my 73 EB from so cal to Boise, ID. My axle seals at the pumpkins appear to have dried up in the cold weather this winter as I now have leaks at both. So will be changing both, any recommendations on gear oil, it’s a weekend driver and sees dirt but not a crawler.
Community
Message Forum
Photo Gallery
Event Calendar
Book Reviews
Bronco Wallpaper
Bronco FAQ
Link Back to CB!
Photo Gallery
Event Calendar
Book Reviews
Bronco Wallpaper
Bronco FAQ
Link Back to CB!
Buy / Sell
Bronco Tech
3 Arm Wiper Setup
Fix Motor Mount
Roll Cage Braces
Throttle Body 65mm
Wheel Alignment
Heat Riser Replacement
Vent Window Repair
Center Console Mount
Straighten Bumper
Ford 6R80 6 spd
More Tech...
Fix Motor Mount
Roll Cage Braces
Throttle Body 65mm
Wheel Alignment
Heat Riser Replacement
Vent Window Repair
Center Console Mount
Straighten Bumper
Ford 6R80 6 spd
More Tech...
-
Welcome to ClassicBroncos! - You are currently viewing the forums as a GUEST. To take advantage of all the site features, please take a moment to register. It's fast, simple and absolutely free. So please join our community today!If you have problems registering or can't log into your account, please contact Admin.
Gear oil
- Thread starter Flyfisen
- Start date
Hi, some guys call the differential housing the pumpkin. I think you mean the axles seals at the ends of the axle tubes are leaking. Whenever I see both seals blow out I assume the vent is clogged so make sure the vent is open. Also check the bearings. If the brake shoes are contaminated just change them. Good luck
I'm assuming your leak is where the third member bolts up. I just rebuilt my rear drums and decided to replace the wheel bearings and seals. I went with a Lubelocker gasket for the third member. Sealed up perfectly without any additional sealant.
Edit: While I had everything apart, I also decided to drill and tap the bottom end of housing and installed a 1/8" NPT plug. Looking forward to being able to drain it that way instead of having to crack it open. I put it on the lower backside of the axle so that it's out of the way.
You are right and I have been schooled on the rear axle diff cover. It is leaking from the third member gasket, I have no issues with the rear axle leaks or gear lash, except for the leak at the gasket. Should I let it drip? Do I have to pull the axles to replace the third member gasket ?
Yep, you need to pull the axles to remove the 3rd member.
I was just digging around for gear lube info for the Ford 9", and ran across this info from Currie:
https://www.currieenterprises.com/currie-85w-140-racing-gear-oil
They are suggesting that GL-6 non-synthetic is the right lubricant for the high offset on a 9" gearset. GL-6 is considered to be an obsolete spec though with most GL-5's meeting it. Currie has something to sell, but they also have been building 9" rear ends for the last 50 years. So...there's that.
Yep, they are trying to sell 'racing' gear oil to people who will never see a race track unless they happen to tune their tv to the correct channel.
- Joined
- Mar 8, 2007
- Messages
- 81,779
may as well pull it and replace the gasket..
I HATE leaks so I may be the wrong person to ask. That said, it wasn't too difficult to do and I now know exactly when my rear axle was serviced. The third member is about 70 pounds and a bit awkward, but lifting it out and putting it back were the hardest part...and still not that bad.
Here was my process. I drove it around first to heat the gear oil a bit.
1. Used a cheap oil pump to remove some of the gear oil.
1b. Pulled both axles
2. Cracked open the third member and let it all drain.
3. Pulled both seals from the axle housing.
4. Pulled the third member completely. The copper washers will fight you in a couple of locations so be creative and patient.
5. Wiped the remaining oil and 46 years of gunk from the bottom of the housing.
6. Drilled and tapped the backside of the housing for a 1/8" NPT plug (will make changing the gear oil a LOT easier next time).
7. Ordered Timken axle bearings and had my local mechanic remove the old ones and press on the new ones.
8. Drove in new axle seals.
9. Cleaned up the third member and axle housing surfaces.
10. Placed the Lubelocker gasket over the studs (Lubelocker label will orient on the passenger side, at the 9 o'clock position).
11. Used a floor jack to help lift the third member close to its final destination.
12. Install the nuts, new copper washers, and torque following the Lubelocker illustration they provide.
13. Rebuild/service rear drum components.
14. Place a little oil on the axle seals and carefully slide the axles home.
15. When everything is buttoned up, fill with the gear oil of your choosing. I ended up using conventional 80w90.
It took me parts of several days but it was well worth it in my opinion. I was happy to replace 46 year-old bearings and seals (and mine weren't even leaking). Peace of mind, and all that....
Last edited:
I'm good at creating work for myself......and others. I rebuilt my rear drum brakes but you may not need to. The only other part I needed was a 1/8" NPT tap, and a 1/8" NPT plug. You may decide to forego that part but I was glad I did it. Here are the posts that took me down that path (mine is the same as post #4 in that thread): https://classicbroncos.com/forums/showthread.php?t=154396
I bought my gasket and washers from Summit Racing.
Gasket: https://www.summitracing.com/parts/lub-llr-c900
I bought my bearings from TBP: https://www.tomsbroncoparts.com/product/2925T-axle-bearing-rear-large-3-18-new
Don't order the bearing set that I've listed, without checking to see if that's what you have in yours. If you're not sure what axle you have, here's a good place to start (of course measuring yours is best):
If you decide to drill and tap the housing for an NPT plug, make sure you don't run the tap too far into the housing. An NPT tap is tapered, and that's what will control the seating depth of your plug.
Happy to "help" over the phone. I'm retired so I got nothin' goin' on.
.....adding to my post immediately above since the links weren't working.
Here's where I got the copper washers: https://www.summitracing.com/parts/rat-5138
And here's some assistance on determining which axle you have: https://www.wildhorses4x4.com/category/bronco_rear_axle
I painted my third member back to its original red when I had mine out. Lastly, safety first. Make sure you've got your rig on some good stands while working under there. No workarounds.
Here's where I got the copper washers: https://www.summitracing.com/parts/rat-5138
And here's some assistance on determining which axle you have: https://www.wildhorses4x4.com/category/bronco_rear_axle
I painted my third member back to its original red when I had mine out. Lastly, safety first. Make sure you've got your rig on some good stands while working under there. No workarounds.
Thanks twodogs, retired here too. Finding I can’t get around under the rig like I use too but always on stands. I’ve got to work my way back from front axle and transfer case as I change fluids. Oh man rear axle sounds like a big job, maybe save till the winter hibernation and drive the hell out of it this summer��
- Joined
- Mar 8, 2007
- Messages
- 81,779
LOL, I know that feeling..
I'm good at creating work for myself......and others. Happy to "help" over the phone. I'm retired so I got nothin' goin' on.
Congrats on retirement; 'tis wonderful! Thought I'd mention the safety issue after seeing some really poor stand alternatives (e.g., cinder blocks). Sounds like you're going the same route that I did. I worked the front end first (with a disc brake conversion) and just now got to the rear components. I'm far from a mechanic but I didn't think it was too bad. Mostly tedious. It would make an excellent winter project and now you have links to some of the parts. Enjoy the summer.
