Rear Differential
Thread Starter
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Senior User
Joined: Aug 2020
Posts: 137
Likes: 1
Rear Differential
Today I replaced my rear axel vent valve (never knew I needed one), but it was plugged and had no hose attached. So, new plug, new hose. The reason I did this is because I was leaking oil from around the old valve. Oil was dirty, and after a half hour ride, the gear housing was warm to the touch.
Two questions
1. I assume since the oil is dirty I need to flush and replace the differential fluids, correct?
2. Is it normal for the gear housing to be warm to the touch after driving?
Two questions
1. I assume since the oil is dirty I need to flush and replace the differential fluids, correct?
2. Is it normal for the gear housing to be warm to the touch after driving?
Grumpy goat
Joined: May 2017
Posts: 3,058
Likes: 594
You have a 9"? If so, I would at least use a hose on a syphon pump to get out as much oil as possible, then refill. If I suspected that dirt got in the housing, I'd pull the axle shafts, and the third member, then thoroughly clean the housing and gears. Yes, the housing will be warm after driving.
Thread Starter
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Senior User
Joined: Aug 2020
Posts: 137
Likes: 1
You have a 9"? If so, I would at least use a hose on a syphon pump to get out as much oil as possible, then refill. If I suspected that dirt got in the housing, I'd pull the axle shafts, and the third member, then thoroughly clean the housing and gears. Yes, the housing will be warm after driving.
Thanks Ranger
Grumpy goat
Joined: May 2017
Posts: 3,058
Likes: 594
You're welcome Colemater.
How'd you route your hose? I have all mine routed up, then turned down, and zip tied of course. I try to remember to check them every time I grease universal joints. Dang dirt daubers love an open ended 3/8" hose.
How'd you route your hose? I have all mine routed up, then turned down, and zip tied of course. I try to remember to check them every time I grease universal joints. Dang dirt daubers love an open ended 3/8" hose.
Thread Starter
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Senior User
Joined: Aug 2020
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I bought 3 ft of hose and routed it over the two rear gas tank straps and pointed it down. Zip tied it to the gas tank strap
FTE Legend
Joined: Nov 2015
Posts: 30,855
Likes: 4,105
From: Angier, NC
A fuel filter on the end of the hose helps on keeping dirt out as when it cools it pulls in air and anything with it.
Some trucks, 4x4's?, use a little valve type thing in the end of the hose but the filter works and is easier to come by.
BTW if 4x4 the front axle would also have a vent and that hose also routed up high like the rear to keep water from getting in when going through deep water.
Dave ----
Some trucks, 4x4's?, use a little valve type thing in the end of the hose but the filter works and is easier to come by.
BTW if 4x4 the front axle would also have a vent and that hose also routed up high like the rear to keep water from getting in when going through deep water.
Dave ----
Thread Starter
|
Senior User
Joined: Aug 2020
Posts: 137
Likes: 1
A fuel filter on the end of the hose helps on keeping dirt out as when it cools it pulls in air and anything with it.
Some trucks, 4x4's?, use a little valve type thing in the end of the hose but the filter works and is easier to come by.
BTW if 4x4 the front axle would also have a vent and that hose also routed up high like the rear to keep water from getting in when going through deep water.
Dave ----
Some trucks, 4x4's?, use a little valve type thing in the end of the hose but the filter works and is easier to come by.
BTW if 4x4 the front axle would also have a vent and that hose also routed up high like the rear to keep water from getting in when going through deep water.
Dave ----
That’s a great idea
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Lead Driver
Joined: Jul 2017
Posts: 9,564
Likes: 1,157
From: San Jose, CA
Another really good reason to do the lube maintenance is checking the rear wheel bearings. Yes, as was said the housing will get warm under just normal use even when everything is in perfect shape, but since we can't tell what you consider warm or hot, it's best not to take chances.
I forget what year your truck is, but older lighter duty F100/150's had sealed ball bearings on the axles. These are good for approx 120,000 miles or so. But if they're original, then it's time to replace them just from old age!
If you have the later truck, or one of the heavier duty early ones, you have tapered roller axle bearings that take 100% of their lubrication from the gear oil in the differential. As you can imagine, this is an even more important reason to change your oil!
Nobody wants to have their rear wheel/axle bearings turn to dust while out on a highway trip out of town!
Paul
I forget what year your truck is, but older lighter duty F100/150's had sealed ball bearings on the axles. These are good for approx 120,000 miles or so. But if they're original, then it's time to replace them just from old age!
If you have the later truck, or one of the heavier duty early ones, you have tapered roller axle bearings that take 100% of their lubrication from the gear oil in the differential. As you can imagine, this is an even more important reason to change your oil!
Nobody wants to have their rear wheel/axle bearings turn to dust while out on a highway trip out of town!
Paul
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