Cause of leaking rear seal?

Reply

  #1  
Old 02-17-13, 11:18 AM
Member
Thread Starter
Join Date: Nov 2008
Location: USA
Posts: 1,160
Cause of leaking rear seal?

2003 Chevy Silverado V8 Auto. 54,000 mi.
Constant 1 to 2 foot dia. puddle under area where drive shaft comes out of trans. housing. Have to add fluid every 6 mo. or so. Vehicle only used once every few months to go to L. or HD. It's started and driven a few mi. at least every month to keep battery charged.

I suspect the #1 cause of the leak is due to inactivity...perhaps the seal is drying out. But I'm wondering about another possible contributing factor: The P/U is always parked on a slightly sloping part of the driveway, not so steep, that would suggest applying parking brake first, but certainly enough that the vehicle would roll forward. Knowing that there would be very little pressure on the trans. parking pawl, I never set the parking brake. I'm wondering if the constant torque, however slight, causes a lateral or sideways force on the output shaft near the rear seal, that would eventually deform the seal.

Anticipating this possibility, I've started using small blocks against both front tires, to allow the vehicle to "rest" against before putting into Park.

Of course, the damage is already done, so question #2 is, how expensive is it to replace this seal?

Thank You.
 
Sponsored Links
  #2  
Old 02-17-13, 12:25 PM
the_tow_guy's Avatar
Group Moderator
Join Date: Feb 2001
Location: SW Fla USA
Posts: 11,531
I don't know about yours in particular, but generally it's a quick, cheap fix. Block wheels, disconnect u joint, pull yoke out of tranny, pry old seal out, pop in new one, reinstall everything.
 
  #3  
Old 02-17-13, 02:20 PM
chandler's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Dec 2005
Location: USA
Posts: 39,968
Mark yoke and drive shaft so you can put them back in the same order. Sometimes wear factor will cause a balance problem if they are rotated. But, as TG said, it's fairly straight forward. Drive the new one in with a wooden block and drive it straight, pointed in the right direction.
 
  #4  
Old 02-20-13, 06:33 AM
Member
Join Date: Oct 2010
Location: USA
Posts: 563
I've never seen a wear issue on a slip yoke by it being repositioned, if there is then the yoke and/or the output shaft needs replacing.

While changing the seal, inspect the slip yoke for damage where it rubs the seal. Make sure that there isn't something prematurely wearing the seal. If there is, have a driveshaft shop put on a new yoke or go get a whole new/used driveshaft from a junkyard.
 
  #5  
Old 02-20-13, 04:31 PM
chandler's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Dec 2005
Location: USA
Posts: 39,968
TWX, not so much the slip yoke itself, but the entire component driveshaft. I think I should have redacted that as it is not so much the yoke itself, but when yoke bearing cups are changed, they must be in the same order, and not 90 degrees off. Vibrations can occur. If the cups are not being changed, then there should be no problem.
 
  #6  
Old 02-20-13, 06:18 PM
Member
Thread Starter
Join Date: Nov 2008
Location: USA
Posts: 1,160
Thank you gentlemen. Well, having never disconnected a u-joint, what tools do I need; can you expound a little on the procedure?
 
  #7  
Old 02-21-13, 03:07 AM
chandler's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Dec 2005
Location: USA
Posts: 39,968
Better to remove the rear u-joint and replace it with a new one, if the car has any age on it. 7/16" boxed end offset wrench is used to remove the U bolts that surround the cups. 4 bolts and the drive shaft will release, along with the ujoint, which may fall into a kazillion pieces, or it may come out intact. I'd replace it anyway.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes
'