Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 09-15-2008, 01:02 AM
Registered User
 
Join Date: Jul 2007
Posts: 517
Rear differential whine?

Hey guys,

I went to Enrique's shop on Saturday morning to get a replacement differential put into my 300DT as well as some other misc stuff. All was fine and dandy until I got up to freeway speeds. Around 45mph and upwards, there is a distinct whining sound from the rear of the vehicle. Its even more pronounced because the back seat is out. I only hear the sound when I depress the throttle. It immediately disappears when I let go. Is that a classic sign of a differential that's worn out? Will adding new gear oil help? Or is that a bandaid for the true cause of this noise?

Bob

Reply With Quote
  #2  
Old 09-15-2008, 10:41 AM
Registered User
 
Join Date: Jul 2007
Posts: 517
bump for monday morning crowd. help!
Reply With Quote
  #3  
Old 09-15-2008, 11:01 AM
UriahT's Avatar
Registered User
 
Join Date: Feb 2008
Location: NYC
Posts: 387
I don't understand- this is the replacement differential that is whining?
A whine from the rear is, yes, probably the diff.
Wheel bearings make a moaning or grumbling sound (gotta love descriptions of sound), and would not let up with your foot off the accelerator.
Axles make a nasty thumping (ask me how I know).
If you got a replacement, chances are the fluid level is good. Adding more will not help. Some folks like to put a thicker fluid in there (straight 90) to reduce the noise some. But it probably won't get rid of the whine altogether. It's a worn differential when it starts whining.
__________________
I-------------------------------------1981 300TD, Thistle Green, 140K------------------------------------I
Reply With Quote
  #4  
Old 09-15-2008, 11:31 AM
vstech's Avatar
DD MOD, HVAC,MCP,Mac,GMAC
 
Join Date: Mar 2006
Location: Mount Holly, NC
Posts: 26,835
whine under load is classic ring gear wear... I hope you didn't pay much for the diff.
__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!
Reply With Quote
  #5  
Old 09-15-2008, 01:16 PM
babymog's Avatar
Loose Cannon - No Balls
 
Join Date: Jan 2006
Location: Northeast Indiana
Posts: 10,765
Worn gears, or improperly set gears. Did they replace the internals or the whole case with internals?

Probably will run 100,000 more miles if there is good fluid and no significant backlash/play.
__________________

Gone to the dark side

- Jeff
Reply With Quote
  #6  
Old 09-15-2008, 01:54 PM
winmutt's Avatar
85 300D 4spd+tow+h4
 
Join Date: Apr 2006
Location: Atl Gawga
Posts: 9,346
How do you determine play in a diff? Remove the DS and axles?
__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42
Reply With Quote
  #7  
Old 09-15-2008, 02:08 PM
UriahT's Avatar
Registered User
 
Join Date: Feb 2008
Location: NYC
Posts: 387
Quote:
Originally Posted by winmutt View Post
How do you determine play in a diff? Remove the DS and axles?
I've always determined play by grabbing the rear driveshaft and trying to rotate. Some don't budge, some can turn almost a half revolution into the diff. A diff with a lot of play often clunks when you put the car in gear, as the shaft rotates before the diff locks into its gearing.
__________________
I-------------------------------------1981 300TD, Thistle Green, 140K------------------------------------I
Reply With Quote
  #8  
Old 09-15-2008, 05:39 PM
Registered User
 
Join Date: Jul 2007
Posts: 517
Thanks for the info guys. I confirmed this with Enrique over the phone who just ordered another replacement diff for me. I"m going to get this installed sometime this week or by Sat. I'll update the thread later

Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

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 On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 11:18 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page