The Ford Barn

newshirt · 01-30-2017, 05:15 PM

I want to verify the rear hub seal (and rear inner axle seal) orientation before pressing them in.

I believe the seals are oriented with the metal spring toward the grease. My attached photo shows the outsides of the seals, oriented away from the grease, true?

Can anyone confirm?

JDupuis · 01-30-2017, 05:27 PM

That's how I mount them.

Bob C · 01-30-2017, 05:33 PM

I'll save myself a thousand words.

Bob

Tom Endy · 01-30-2017, 06:30 PM

The original inner hub seals were made of leather. One of Fords suppliers was Chicago Rawhide. Quite often the original seals are found still in place during an overhaul. The letters CR are found stamped on the side. Most of the leather is usually deteriorated.

It made sense to install them such that when the axle slid into place it did not fold the leather back on itself.

Modern replacement seals are made of neoprene. Supplier's literature say to face the taper on the seal toward the lubricant. There is a taper on both sides of the seal and it is not specified what lubricant they are talking about, the oil in the banjo or the grease that is pumped into the rear wheel bearing.

The seal is a grease seal, not an oil seal. Its purpose is to prevent the grease that is pumped in through the grease fitting on the rear backing plate from migrating down the axle shaft toward the differential instead of going outboard to the rear wheel bearing.

People continue to argue about the purpose of the seal and which direction to face it. If you have ever pulled a rear end apart that had the original shot seals installed and an owner who religiously pumped grease into the grease fitting on the backing plate you would find that grease has centrifuged around the axle an inch thick and is as long toward the differential as the owner's frequency of pumping grease into it.

I don't think it matters which direction you face the seal, either way it will snap into the slight groove in the axle and it will do the job.

It is best to pack the rear wheel bearings when you have the drum off and forget about that grease fitting. Ford eliminated it during the early V8 years.

Tom Endy

stengel · 02-09-2020, 11:37 AM

Newbie here so I put what I call the open end toward the bearing that I greased ,CORRECT? It seams that the grease would eventually fill the opening that is in the seal side with the spring in it ???? WOW.

DBrer · 02-09-2020, 11:51 AM

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Thats how I would install a seal.

Jim Brierley · 02-09-2020, 11:53 AM

stengel, correct, the seals are to keep the grease in the wheel bearing.

redmodelt · 02-09-2020, 01:06 PM

I put mine on so any part that slides into or onto you don't have to fight the taper in the seal so the open side is to the grease not away. When grease is added, you want the lip to be pushed to seal, not pushed to open and allow the grease past.

01-30-2017, 05:27 PM	#2
JDupuis Senior Member Join Date: Jan 2017 Location: Maryhill Ont Canada Posts: 834	Re: Hub seal orientation That's how I mount them.

01-30-2017, 06:30 PM	#4
Tom Endy Senior Member Join Date: May 2010 Location: Southern California Posts: 3,131	Re: Hub seal orientation The original inner hub seals were made of leather. One of Fords suppliers was Chicago Rawhide. Quite often the original seals are found still in place during an overhaul. The letters CR are found stamped on the side. Most of the leather is usually deteriorated. It made sense to install them such that when the axle slid into place it did not fold the leather back on itself. Modern replacement seals are made of neoprene. Supplier's literature say to face the taper on the seal toward the lubricant. There is a taper on both sides of the seal and it is not specified what lubricant they are talking about, the oil in the banjo or the grease that is pumped into the rear wheel bearing. The seal is a grease seal, not an oil seal. Its purpose is to prevent the grease that is pumped in through the grease fitting on the rear backing plate from migrating down the axle shaft toward the differential instead of going outboard to the rear wheel bearing. People continue to argue about the purpose of the seal and which direction to face it. If you have ever pulled a rear end apart that had the original shot seals installed and an owner who religiously pumped grease into the grease fitting on the backing plate you would find that grease has centrifuged around the axle an inch thick and is as long toward the differential as the owner's frequency of pumping grease into it. I don't think it matters which direction you face the seal, either way it will snap into the slight groove in the axle and it will do the job. It is best to pack the rear wheel bearings when you have the drum off and forget about that grease fitting. Ford eliminated it during the early V8 years. Tom Endy

02-09-2020, 11:37 AM	#5
stengel Junior Member Join Date: Jan 2015 Posts: 6	Re: Hub seal orientation Newbie here so I put what I call the open end toward the bearing that I greased ,CORRECT? It seams that the grease would eventually fill the opening that is in the seal side with the spring in it ???? WOW.

02-09-2020, 11:51 AM	#6
DBrer Senior Member Join Date: Oct 2019 Location: Washington Posts: 175	Re: Hub seal orientation Sponsored Links (Register now to hide all advertisements) Thats how I would install a seal.

02-09-2020, 11:53 AM	#7
Jim Brierley Senior Member Join Date: Jun 2010 Location: Temecula, CA Posts: 4,087	Re: Hub seal orientation stengel, correct, the seals are to keep the grease in the wheel bearing.

02-09-2020, 01:06 PM	#8
redmodelt Senior Member Join Date: May 2010 Location: Portland OR Posts: 6,340	Re: Hub seal orientation I put mine on so any part that slides into or onto you don't have to fight the taper in the seal so the open side is to the grease not away. When grease is added, you want the lip to be pushed to seal, not pushed to open and allow the grease past. __________________ I know the voices aren't real but damn they have some good ideas!