Rear end chatter...

CSIPSD · May 18, 2012

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.

Arisley · May 18, 2012

Could be. The friction modifier that was in the grease when you put it in may also be wearing out. Might try adding some friction modifier.

CSIPSD · May 18, 2012

I did when I changed the fluid a few weeks ago. Didnt seem to help any.

Looking to see if anyone else has ideas as to a differant cause?

Any vendors sell a rebuild kit for the factory LS?

onebad7.3 · May 18, 2012

CSIPSD said:
I did when I changed the fluid a few weeks ago. Didnt seem to help any.

Looking to see if anyone else has ideas as to a differant cause?

Any vendors sell a rebuild kit for the factory LS?

Sunrise ford seems to have good prices the last time I check. Too bad shipping would probably kill us or I'd send you my diff, just had it rebuilt 1,000 miles ago

CSIPSD · May 18, 2012

Where are you located? I am in Great Falls, MT right now...

kyle43335 · May 18, 2012

CSIPSD said:
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.

are bolth wheels hard to turn in the same direction? or are they hard to turn one forward,the other backward(cycling the spiders)

if its the second one? it will be the friction material gone,and you only have the steels grinding off one another.

the first one would be something different,cause with bolth wheels spinning the same direction,your not cycling the spiders.

onebad7.3 · May 18, 2012

CSIPSD said:
Where are you located? I am in Great Falls, MT right now...

Long ways away. Roughly 1,600 miles to the east. Located in MI

CSIPSD · May 18, 2012

No, its when you try and move them in the other direction, or when you hold one and spin the other.

CSIPSD · May 18, 2012

onebad7.3 said:
Long ways away. Roughly 1,600 miles to the east. Located in MI

well crap...LOL

Dave · May 18, 2012

Add the friction modifier.

not having it in it ate up the LS

Charles · May 18, 2012

Truetrac...

They don't need pu$$y ass additives to get the jone done and do a hell of a lot better job anyway. And you can run synthetic fluid, or whatever else floats your boat.

BTW.... if you put synthetic in with the stock LSD on that oilchange, that may be your problem right there.

CSIPSD · May 18, 2012

Dave said:
Add the friction modifier.

not having it in it ate up the LS

I understand that, but does everyone agree thats got to be what it is? I want to get the parts ordered to rebuild it.

SICKS LITER · May 18, 2012

if you are turning both the wheels in the same direction and theres binding, shuttering, or whatever than that is not a posi problem. it could be brakes, bearings, ring/pinion, pinion/driveshaft angle, u joints.

CSIPSD · May 18, 2012

Charles said:
Truetrac...

They don't need pu$$y ass additives to get the jone done and do a hell of a lot better job anyway. And you can run synthetic fluid, or whatever else floats your boat.

BTW.... if you put synthetic in with the stock LSD on that oilchange, that may be your problem right there.

I'd love to do that, and it might be cheaper parts wise, but from what I am being told I would have to completely reset the rear end. I am confident enough to remove the carrier and rebuild the factory LS, but not set up a gear set. If your telling me I could swap out the Factory LS for a truetrac and not rebuild or reset the rear end I would prefer to go that way.

I told ford to install a true trac in my rear end when it blew... thought they did until a few months ago when I noticed this scribbled on the invoice...

kyle43335 · May 18, 2012

CSIPSD said:
No, its when you try and move them in the other direction, or when you hold one and spin the other.

def clutches

Charles said:
Truetrac...

They don't need pu$$y ass additives to get the jone done and do a hell of a lot better job anyway. And you can run synthetic fluid, or whatever else floats your boat.

BTW.... if you put synthetic in with the stock LSD on that oilchange, that may be your problem right there.

the factory 75/140 is synthetic

kyle43335 · May 18, 2012

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2001 Ford Truck F 250 4WD Super Duty V8-7.3L DSL Turbo VIN F
Vehicle Level Transmission and Drivetrain Differential Assembly Specifications Fluid Type Specifications

Fluid Type Specifications

Ford 10.50 Inch Ring Gear & Dana S135 - Rear Drive Axle

SAE 75W140 High Performance Rear Axle Lubricant F1TZ-19580-B
Specification WSL-M2C192-A
Additive Friction Modifier C8AZ-19B546-A
Specification EST-M2C118-A
Dana 80 - Rear Drive Axle

SAE 75W90 Thermally Stable Multi-Purpose Gear Lubricant XY-75W90-QL
Specification WSP-M2C201-A
Additive Friction Modifier C8AZ-19B546-A
Specification EST-M2C118-A

Charles · May 18, 2012

kyle43335 said:
def clutches

[/COLOR]

the factory 75/140 is synthetic

Maybe it's Auburn that can't take the synthetic then.

Charles · May 18, 2012

CSIPSD said:
I'd love to do that, and it might be cheaper parts wise, but from what I am being told I would have to completely reset the rear end. I am confident enough to remove the carrier and rebuild the factory LS, but not set up a gear set. If your telling me I could swap out the Factory LS for a truetrac and not rebuild or reset the rear end I would prefer to go that way.

I told ford to install a true trac in my rear end when it blew... thought they did until a few months ago when I noticed this scribbled on the invoice...

You could leave the pinion alone and just swap everything over to the new carrier, but you would at minimum want to get the backlash right with a dial indicator. Which is super easy.

I would also get some new carrier bearings to avoid the bullsh*t involved with knifing the old ones off. You'll need a shop press to install the carrier bearings onto the carrier.

Although you could have that done by anyone, as you can do it before you even take the truck apart, and just have it done and ready.

It's up to you, but setting backlash and swapping carriers isn't really a big deal in terms of brain power. Just leave the pinion alone and assume the depth is good to go, which it will be, as you're not altering anything to change that.

SICKS LITER · May 18, 2012

as charles said all you would have to do is set backlash, very very easy.

also check your side gears and pinion gears in the differential, broken or damaged teeth will cause issues as well.