Differential seals question: overfill or leaky seal?
04-20-2016, 09:02 AM
#21
With the car LEVEL, drive train COLD, remove the fill. When you remove it, there should be a very slight in rush of air into the differential (vacuum)
If the vent is working correctly, it will let pressure out but should seal if there isn't any pressure. When it seal and the diff case cools, a small vacuum forms inside the case.
This vacuum helps the output shaft seals SEAL.
If the car is level and you remove the fill plug, any overfill will run out.
Bill
If the vent is working correctly, it will let pressure out but should seal if there isn't any pressure. When it seal and the diff case cools, a small vacuum forms inside the case.
This vacuum helps the output shaft seals SEAL.
If the car is level and you remove the fill plug, any overfill will run out.
Bill
09-24-2016, 01:22 PM
#22
I noticed a small drip on my garage floor, left side of car. After reading some posts I concluded it was coming from the vent. I put the rear end in the air and there it was, a tiny pool of oil sitting in one of the crevasses next to the vent, which dripped down on to the left side of the leaf spring. I am the 2nd owner of an 04 with 12k on it so I assume it still has factory fluid in it. Should I be concerned, is it normal for the factory to overfill?
Last edited by rayz1951; 09-24-2016 at 01:24 PM.
09-24-2016, 02:39 PM
#23
Melting Slicks
I noticed a small drip on my garage floor, left side of car. After reading some posts I concluded it was coming from the vent. I put the rear end in the air and there it was, a tiny pool of oil sitting in one of the crevasses next to the vent, which dripped down on to the left side of the leaf spring. I am the 2nd owner of an 04 with 12k on it so I assume it still has factory fluid in it. Should I be concerned, is it normal for the factory to overfill?
04-05-2017, 05:20 PM
#24
on mine it only leaks when car sits for few days then once I start it and start to back out then that's when it starts to leak what do you think it could be
04-05-2017, 07:35 PM
#25
Tech Contributor
Member Since: Dec 1999
Location: Anthony TX
Posts: 32,736
Received 2,180 Likes
on
1,583 Posts
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The vent is suppose to let pressure escape and seal when no pressure is present. It consist of a little rubber disk and a small spring that puts slight pressure on the seal.
Under normal conditions when the differentiall is cold, the sealed vent allows a very slight vacuum to form as the diff cools down. That helps it keep the lube in.
If you remove the fill plug and have a very slight inrush of air, the seal is functioning correctly.
Some people remove the vent guts and put a rubber hose on it to help keep the oil from leking out. Kind of like the vent hose on a 4X4.
Make SURE that the diff has the correct oil level in it. DO NOT overfill it.
Bill
Under normal conditions when the differentiall is cold, the sealed vent allows a very slight vacuum to form as the diff cools down. That helps it keep the lube in.
If you remove the fill plug and have a very slight inrush of air, the seal is functioning correctly.
Some people remove the vent guts and put a rubber hose on it to help keep the oil from leking out. Kind of like the vent hose on a 4X4.
Make SURE that the diff has the correct oil level in it. DO NOT overfill it.
Bill
04-06-2017, 08:36 AM
#26
The vent is suppose to let pressure escape and seal when no pressure is present. It consist of a little rubber disk and a small spring that puts slight pressure on the seal.
Under normal conditions when the differentiall is cold, the sealed vent allows a very slight vacuum to form as the diff cools down. That helps it keep the lube in.
If you remove the fill plug and have a very slight inrush of air, the seal is functioning correctly.
Some people remove the vent guts and put a rubber hose on it to help keep the oil from leking out. Kind of like the vent hose on a 4X4.
Make SURE that the diff has the correct oil level in it. DO NOT overfill it.
Bill
Under normal conditions when the differentiall is cold, the sealed vent allows a very slight vacuum to form as the diff cools down. That helps it keep the lube in.
If you remove the fill plug and have a very slight inrush of air, the seal is functioning correctly.
Some people remove the vent guts and put a rubber hose on it to help keep the oil from leking out. Kind of like the vent hose on a 4X4.
Make SURE that the diff has the correct oil level in it. DO NOT overfill it.
Bill
04-06-2017, 03:01 PM
#27
With the car LEVEL, drive train COLD, remove the fill. When you remove it, there should be a very slight in rush of air into the differential (vacuum)
If the vent is working correctly, it will let pressure out but should seal if there isn't any pressure. When it seal and the diff case cools, a small vacuum forms inside the case.
This vacuum helps the output shaft seals SEAL.
If the car is level and you remove the fill plug, any overfill will run out.
Bill
If the vent is working correctly, it will let pressure out but should seal if there isn't any pressure. When it seal and the diff case cools, a small vacuum forms inside the case.
This vacuum helps the output shaft seals SEAL.
If the car is level and you remove the fill plug, any overfill will run out.
Bill
