Transfer Case Leak
Thread Starter
|
Freshman User
Joined: Mar 2005
Posts: 35
Likes: 0
Transfer Case Leak
Hi there. I have a 1979 f150 4x4 with a 351m. The transfer case is leaking from the front output shaft. I am getting ready to change the seal. Do I have to pull the transfer case or can I pull the front driveline and pop out the seal then replace? Does the yoke just pull out? Any help would be appreciated. Thanks,Troy
Postmaster
Joined: Jul 2005
Posts: 3,248
Likes: 0
The front output seal can be replaced with out pulling the transfer case. If truck is equipped with skid plate, remove skid plate to make access of seal more accessable.
The u-bolts must be removed to remove driveshaft from transfer case.
The yoke on transfer case must be removed. The seal must be removed with a seal puller. Keep old seal to match up with new oil seal. Verify that the yoke does not have any grooves on the portion where the oil seal and yoke make contact. Be carefull not to damage new oil seal on installation.
The u-bolts must be removed to remove driveshaft from transfer case.
The yoke on transfer case must be removed. The seal must be removed with a seal puller. Keep old seal to match up with new oil seal. Verify that the yoke does not have any grooves on the portion where the oil seal and yoke make contact. Be carefull not to damage new oil seal on installation.
Posting Guru
Joined: Feb 2002
Posts: 2,404
Likes: 3
From: Cleveland, WI USA
You can do it with the case in. Remove the big nut and pull the yoke off. Pull the seal and pop in a new one.
You can also remove the 4 nuts that hold the aluminum housing on and take the housing off. That'll make it a lot easier. Also, check the surface of the yoke for grooving, and replace it if it's damaged.
Hope this helps.
Kevin K.
You can also remove the 4 nuts that hold the aluminum housing on and take the housing off. That'll make it a lot easier. Also, check the surface of the yoke for grooving, and replace it if it's damaged.
Hope this helps.
Kevin K.
Postmaster
Joined: Apr 2003
Posts: 3,587
Likes: 0
From: Virginia Beach
welp, it shouldn't be but 4 bolts to take the front drive line out. Drop it from the Tcase, and look inside the yoke. If it has a big nut in there, then I would see why it couldn't be dealt with like newer Tcases. Remove the nut, use a 2 jaw puller if need be and remove the yoke. Pry out the old seal, clean up the seal bore in the Tcase, make sure no dirt gets/got in and tap the new seal in.
Now, why is the seal leaking? Is it worn/craked? Or does it have a groove worn in wear the seal seats? If there is a groove, you might need to put a repair sleeve on the yoke, else a new seal will leak too. Repair sleeves should be available at the same place as the seal (just about any quicky Auto-store)
EDIT: This is why you shouldn't answer a PM while answering another question, then back paging and post
Now, why is the seal leaking? Is it worn/craked? Or does it have a groove worn in wear the seal seats? If there is a groove, you might need to put a repair sleeve on the yoke, else a new seal will leak too. Repair sleeves should be available at the same place as the seal (just about any quicky Auto-store)
EDIT: This is why you shouldn't answer a PM while answering another question, then back paging and post
Last edited by Franken-Truck; Nov 9, 2005 at 12:12 PM.
Senior User
Joined: Sep 2005
Posts: 214
Likes: 0
watch for the grooves
As said above the grooves will just eat the new seal, you should sleeve the shaft or buy a new yoke if you have any grooves.
Trending Topics
Postmaster
Joined: Jul 2005
Posts: 3,248
Likes: 0
Check out picture of assembly of the transfer case on my gallery.
I've used a fine grit emery cloth and sanded the groves down a bit. Sand the groves smooth and in the same rotation of the grooves. If the grooves are deep put a replacement sleeve or a new yoke.
Once the yoke is off, take the 4 bolts off to remove the bearing retainer off the Transfer case. The seal then can be removed.
When installing the new seal, put some light grease on seal portion where it contacts the yoke, this will ensure that seal does not run dry.
Now would be a good time to inspect the front u-joints and replace if necessary.
Check vent holes for transfer case and make sure that it not plugged or restricted, clean if necessary.
I've used a fine grit emery cloth and sanded the groves down a bit. Sand the groves smooth and in the same rotation of the grooves. If the grooves are deep put a replacement sleeve or a new yoke.
Once the yoke is off, take the 4 bolts off to remove the bearing retainer off the Transfer case. The seal then can be removed.
When installing the new seal, put some light grease on seal portion where it contacts the yoke, this will ensure that seal does not run dry.
Now would be a good time to inspect the front u-joints and replace if necessary.
Check vent holes for transfer case and make sure that it not plugged or restricted, clean if necessary.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!
Joe Kucinski
Every 2026 Ford Truck Engine RANKED from WORST to FIRST!
Michael S. Palmer
The Best F-150 Deal of Every Trim Level (XL through Raptor)
Joe Kucinski
Thread
Thread Starter
Forum
Replies
Last Post
CountryBumkin
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
9
Aug 22, 2014 12:42 PM
John Thomas II
Clutch, Transmission, Differential, Axle & Transfer Case
3
Sep 21, 2013 08:40 AM
79f100six
Clutch, Transmission, Differential, Axle & Transfer Case
2
Sep 10, 2007 02:58 PM
jd_boggs
Clutch, Transmission, Differential, Axle & Transfer Case
2
Jul 13, 2006 07:57 AM
