Notices
1999 - 2003 7.3L Power Stroke Diesel  
Sponsored by:
Sponsored by: DP Tuner

Rear end chatter...

Thread Tools
 
Search this Thread
 
Old May 18, 2012 | 12:17 PM
  #1  
CSIPSD's Avatar
CSIPSD
Thread Starter
|
Postmaster
Joined: Jul 2006
Posts: 4,993
Likes: 2
From: Bend, OR
Rear end chatter...

Long story...

Short version...

Does this sound like the factory limited slip going out?

When ever my wife turns, or accels hard you get a bad shutter, its been getting worse over the last few months.

Took the rear end apart and everything looks fine, but while its up on jack stands its extreamly hard to turn the wheels and will chatter like it does when your driving (altho much slower). Its the only thing I can come up with that would cause this issue.

When I changed the fluid about 3 years ago, I did not add the friction modifier. Forgot, or what ever... Could this cause the clutches to wear out quicker to where the steels are just locking up?

Damn thing feels like it has a locker in it around corners.
 
Reply
Old May 18, 2012 | 12:37 PM
  #2  
Deluxe06's Avatar
Deluxe06
4000 rounds a min
Joined: Apr 2010
Posts: 2,223
Likes: 0
From: Albemarle NC
Club FTE Gold Member
You could try putting some friction modifier in and see if it helps.
 
Reply
Old May 18, 2012 | 12:39 PM
  #3  
CSIPSD's Avatar
CSIPSD
Thread Starter
|
Postmaster
Joined: Jul 2006
Posts: 4,993
Likes: 2
From: Bend, OR
I did... Didnt do much if anything. We are talking YEARS (about 60k) of driving without it. Looking into a rebuild kit for it right now...

Just looking to see if anyone else has ideas what it might be.
 
Reply
Old May 18, 2012 | 01:04 PM
  #4  
valiant500hp's Avatar
valiant500hp
Senior User
Joined: Jun 2003
Posts: 103
Likes: 0
From: Woodland, WA
Sounds like limited slip to me.

My factory one sucked really bad, so when I changed the fluid I didn't add the modifier to make it more aggressive. Now it chatters sometimes on turns and such.

I've been looking into taking it down to Six States and getting a new locker put in, but I've done enough to stimulate the economy this year with truck mods.....
 
Reply
Old May 18, 2012 | 01:56 PM
  #5  
cookie88's Avatar
cookie88
FTE Leadership Emeritus
20 Year Member
Liked
Joined: May 2001
Posts: 13,653
Likes: 6
From: Cabot, Arkansas
FTE Emeritus
Definitely sounds like the LSD to me. Give that ring gear a close inspection while it's down. They'll stress fracture when they overheat. Sometimes you can see it in the web between the teeth.
 
Reply
Old May 18, 2012 | 02:08 PM
  #6  
CSIPSD's Avatar
CSIPSD
Thread Starter
|
Postmaster
Joined: Jul 2006
Posts: 4,993
Likes: 2
From: Bend, OR
Oh the ring gear has some minor chips, but its had those for over 100k... Just looking to loose the chatter. Chelsea is afraid she is going to break something when she corners.
 
Reply
Old May 18, 2012 | 02:12 PM
  #7  
SteveH-CO's Avatar
SteveH-CO
Fleet Mechanic
20 Year Member
Liked
Loved
Community Favorite
Joined: Jul 2005
Posts: 1,800
Likes: 52
From: Southern Colorado
Sometimes, it takes 2 bottles of additive, and you're supposed to do several 'donuts' in each direction (after adding it) to get the additive where it belongs - inside the clutch packs.

I like my tight limited slip (I added only 1 bottle and it chatters a bit), as it helps me get up my driveway in 2WD without locking the hubs.
 
Reply

Trending Topics

Old May 18, 2012 | 06:45 PM
  #8  
ToMang07's Avatar
ToMang07
Logistics Pro
10 Year Member
Liked
Loved
Community Favorite
Joined: May 2011
Posts: 4,832
Likes: 668
From: Maine
Originally Posted by CSIPSD
Oh the ring gear has some minor chips, but its had those for over 100k... Just looking to loose the chatter. Chelsea is afraid she is going to break something when she corners.
Tell her to go straight!
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

 Verdad Gallardo
story-1

Top 10 Fords at 2026 Carlisle Ford Nationals

 Joe Kucinski
story-2

3 Best / 3 Worst Parts of Modern Ford Ownership

 Brett Foote
story-3

10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

 Pouria Savadkouei
story-4

Every 2026 Ford Engine Explained

 Brett Foote
story-5

10 Ugly Ford Trucks That We Still Kinda Love

 Joe Kucinski
story-6

10 Things Every Truck Owner NEEDS (2026 Edition)

 Michael S. Palmer
story-7

Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

 Verdad Gallardo
story-8

Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

 Joe Kucinski
story-9

2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

 Brett Foote
Old May 18, 2012 | 07:42 PM
  #9  
moontrain's Avatar
moontrain
Junior User
Joined: Mar 2009
Posts: 56
Likes: 0
From: Spencerport NY
After changing my fluid I had to add 2 bottles of additive and I was told to do figure 8s and that stopped the chatter.
 
Reply
Old May 18, 2012 | 08:18 PM
  #10  
Whitey Ford's Avatar
Whitey Ford
FTE-Spread The Knowledge
15 Year Member
Liked
Loved
Community Favorite
Joined: Feb 2008
Posts: 2,289
Likes: 246
Club FTE Silver Member

Florida Powertrain told me they rarely see the clutch packs go out. They said the cure 99 percent of the time is new fluid & 3 bottles of the additive.
 
Reply
Old Jul 5, 2014 | 09:16 PM
  #11  
Tcook911's Avatar
Tcook911
New User
Joined: May 2014
Posts: 11
Likes: 0
Additive?

What additive is being referenced here? I'm getting ready to change out mine and I do have a little chatter. Bought. 2002 excursion 7.3 limited 4x4 and slowly working out little issues.
 
Reply
Old Jul 5, 2014 | 09:26 PM
  #12  
cj45lc's Avatar
cj45lc
Cargo Master
Joined: Feb 2010
Posts: 2,298
Likes: 94
From: Delta, CO
Originally Posted by Tcook911
What additive is being referenced here? I'm getting ready to change out mine and I do have a little chatter. Bought. 2002 excursion 7.3 limited 4x4 and slowly working out little issues.
Friction Modifier...some of the 75w140 has it already (Mobil is one that does)
 
Reply
Old Jul 6, 2014 | 12:03 AM
  #13  
Tcook911's Avatar
Tcook911
New User
Joined: May 2014
Posts: 11
Likes: 0
Originally Posted by cj45lc
Friction Modifier...some of the 75w140 has it already (Mobil is one that does)
Thx for the info...
 
Reply
Old Jul 6, 2014 | 08:22 AM
  #14  
Franko72's Avatar
Franko72
Molon Labe
15 Year Member
Joined: Dec 2006
Posts: 5,272
Likes: 1
From: Alaska
Club FTE Silver Member

Originally Posted by Tcook911
What additive is being referenced here? I'm getting ready to change out mine and I do have a little chatter. Bought. 2002 excursion 7.3 limited 4x4 and slowly working out little issues.
Most of the oils that already have the additive do not have enough to meet Ford/Dana's standard. I changed my rear end fluid with the Mobile 1 & added two tubes of TransX.

 
Reply
Old Jul 6, 2014 | 11:34 AM
  #15  
TransBrain's Avatar
TransBrain
Junior User
Joined: Jun 2014
Posts: 67
Likes: 0
Sometimes it can take a few hundred miles for the friction modifier to fully get in and work. I had a Navigator that I had to road test over 400 miles for it to go away. I bet the customer the $140 in fuel I would use that it would. It did. and it was bad.

There is only one type of friction modifier that is the best. No other FM works like the old Ford Racing friction modifier does. It is now sold by Dana Spicer.

Use 2 bottles.

Differential Friction Modifier Additive - Dana Spicer - 43161

This is the only kind I have used for the past 20 years. with success.

Don't waste your money on anything else.

Warning....it stinks....bigtime!!!
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
TxBoi84
2009 - 2014 F150
5
Jun 7, 2018 07:05 PM
wildstang
1999 - 2016 Super Duty
7
Apr 27, 2010 12:22 PM
aocabrown
1999 - 2003 7.3L Power Stroke Diesel
7
Feb 9, 2009 04:33 PM
76F250HighBoy
1997 - 2003 F150
14
Apr 14, 2007 09:03 AM
dzzavid
1999 - 2003 7.3L Power Stroke Diesel
12
Feb 6, 2007 09:28 PM




All times are GMT -5. The time now is 04:28 PM.

story-0
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.

By Verdad Gallardo | 2026-06-12 11:01:55


VIEW MORE
story-1
Top 10 Fords at 2026 Carlisle Ford Nationals

Slideshow: Top 10 Fords at 2026 Ford Nationals

By Joe Kucinski | 2026-06-09 11:10:08


VIEW MORE
story-2
3 Best / 3 Worst Parts of Modern Ford Ownership

Based on years of owning multiple modern Ford products.

By Brett Foote | 2026-06-09 10:53:36


VIEW MORE
story-3
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

SPONSORED: From muddy boots to rain-soaked cargo, these upgrades address some of the most common frustrations Ford truck owners face every day.

By Pouria Savadkouei | 2026-06-08 18:50:34


VIEW MORE
story-4
Every 2026 Ford Engine Explained

Here's everything you need to know about every Ford engine available for the 2026 model year.

By Brett Foote | 2026-06-05 12:58:01


VIEW MORE
story-5
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-6
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-7
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE
story-8
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-9
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE