yo A.O.R.C.,
Ford Parts on-line shows a 2 piece seal;
go to Ford @
http://www.fordparts.com/Commerce/CatalogResults.aspx?y=1991&m=Ford&mo=Bronco#Search
go thru drill,
Select Model
etc.
Engine
View Image PN 6701 (this is the Motorcfat Short Version part number and not good for a general google search since it will apply to different types of Seals
Engine Crankshaft Seal
5.8L (Rear) $29.74 Select a dealer for prices & availability
But @ Rock Auto,
http://www.rockauto.com
They show both one piece & split
Such as;
TIMKEN Part # 2377 Shaft Size: 3.75"; Housing Bore: 4.501"; Seal Width: 0.362"; Seal Outside Dia: 4.506"; Seal Lip Material: FluoroElastomer; Housing Material: Steel; Max Temp: 400°F; Min Temp: -40°F; Seal Type: 350; Press Fit
Viton;
RearShaft Size: 3.75"; Housing Bore: 4.501"; Seal Width: 0.362"; Seal Outside Dia: 4.506"; Seal Lip Material: FluoroElastomer; Housing Material: Steel; Max Temp: 400°F; Min Temp: -40°F; Seal Type: 350; Press Fit
Most Timken seals have the following properties:
Machined rubber sealing edge provides greater accuracy and consistency, as well as a better sealing surface.
A flanged design allows for easier and proper installation and helps avoid cocking.
A latex bore coat seals the outer diameter leak path and helps compensate for minor bore imperfections.
An extra dust lip helps keep harmful contaminants, such as dirt, out of the bearing and protects against rust and corrosion.
FEL-PRO Part # BS40645 Rear Main Seal Set
Type: Rear Main Seal Set; PTFE Rubber; One-piece; Rear
FEL-PRO Part # BS40592 Rear Main Seal Set
Type: Rear Main Seal Set; Rubber; One-piece; Rear
NATIONAL Part # 5117 Oil Seal Kit; Nitrile, Shaft Size=3.438", Outer Diameter=4.313", Width=0.188"
Rear; Split Seal
Trucky has a good article on the replacement in his 5.8;
Installation in a 95 5.8
Source: by TRUCKY18 (Bco) at
http://www.supermotors.net/clubs/superford/registry/3749/29261
such as; "...This is the old seal, nasty and leaky.
These are both new seals from NAPA (I discovered the NAPA Teflon and the Felpro one from advance are the same damn seal accept the NAPA one is 4 bucks cheaper.
On the left is the rubber one and the right is the Teflon, they look about the same, but they ARE NOT.
Upon a closer examination I found the rubber one is tensioned to the crank by a spring because the rubber is very pliable, good for repair sleeves since they are slightly bigger than the original crank diameter. The Teflon one is tensioned to the crank by the stiffness of the material not good for repair sleeves should have listened to the directions. Basically what happened was that the Teflon one went on so tight it spun with the crank instead of the crank spinning in it. SO….if you use a repair sleeve DO NOT USE TEFLON. I personally would say the Teflon is better just because of the nature of Teflon, but as I discovered it does not work in all cases. If you use the rubber one put a small film of non-curing silicone on it so it doesn’t start up dry.
So I did it all over again and put the rubber one on. Went on much easier. After I put it all back together after this go-round, I started it and NO LEAKS!