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3/05/2020 5:35 PM  #1


Installing 9” in my 66

Used transmission jack. Pretty much effortless once the electrician helped me lift it onto the transmission lift.






















Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

3/05/2020 6:48 PM  #2


Re: Installing 9” in my 66

you lost me on the last two pictures........why the bottle jacks?
6sal6


Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
 

3/06/2020 7:41 AM  #3


Re: Installing 9” in my 66

The bottle jacks force the springs down, opening up the space where you have to feed the axle through there at an angle.  Otherwise tailpipe and mufflers are in the way.  The springs are forced down about 3-4” with the jacks.


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
     Thread Starter
 

3/06/2020 9:45 AM  #4


Re: Installing 9” in my 66

Huh I knew that.

Don't look at me in that tone of voice.

 

3/06/2020 10:11 AM  #5


Re: Installing 9” in my 66

I sure hope you drained all the shakes out of it before the install.  We're all gettin' pretty tard of listening to you snivel about that vibration at 130 +.

BB


"you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
 

3/06/2020 7:29 PM  #6


Re: Installing 9” in my 66

Is this a new housing.  Or just new  center section.

 

3/07/2020 2:27 PM  #7


Re: Installing 9” in my 66

Steve-G wrote:

Is this a new housing.  Or just new  center section.

I suspect the only original Ford parts on that axle will be the late model Cobra calipers and discs! 

Speaking of the discs, are they going to fit without some clearancing?  Those axles look beefy!
 

Last edited by Greg B (3/07/2020 2:31 PM)


If multiple things can go wrong, the one that will go wrong will be the one that causes the most damage.
 

3/07/2020 2:57 PM  #8


Re: Installing 9” in my 66

Steve-G wrote:

Is this a new housing. Or just new center section.

I believe he said it was a new Currie housing, all new everything.


 


"you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
 

3/07/2020 9:34 PM  #9


Re: Installing 9” in my 66

The housing and axles are from Currie. All brand new.
The third member is from Strange.  All new Pro nodular case, Eaton true trac differential, 31 spline with Motive Italian 3.50.1 ratio gears.

Test drive results:    Holy -oh no I used a word I shouldn't have- THIS THING MAKES ALOT OF NOISE!!!  It howls and skips noise up and down and is just freaking terrible.  And Strange says they have no warranty on noisiness!!!!   $1,700 for this third member and it makes noise like an old farm truck that somebody dug out of a pasture.  So, I will have to put the old aluminum 3.70 differential back in for the trip. It whines, but only about 10% of the noise this new POS makes.   Unbelievable.

And the harmonic vibration?   It changed a little. Maybe due to different gear ratio.  But still noticeable.  Hardly noticeable due to all my cussing and hollerin’ about the rear end noise.

I am going to start sawzalling exhaust system parts off the car until it goes away.  You know, maybe THAT might actually solve the complaining about the gear noise.


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
     Thread Starter
 

3/08/2020 7:07 AM  #10


Re: Installing 9” in my 66

Disappointing to hear about the noise.  I've got the same rear end (3.5 Eaton Truetrac) except it's all Strange- housing, axles and third member. I hope mine is not the same.

Why didn't you go with Currie for everything?

 

3/08/2020 7:42 AM  #11


Re: Installing 9” in my 66

Is there some sort of break in oil modifier you have to use for a bit?
 

 

3/08/2020 9:01 AM  #12


Re: Installing 9” in my 66

Just wondering who cut the gears. When I put the 3.70 in the 67 I did a lot of research. Brand names mean almost nothing. Part numbers kind of point to who actually made them. 3.70 are never completely quiet by nature.

 

3/08/2020 10:03 AM  #13


Re: Installing 9” in my 66

MS wrote:

The housing and axles are from Currie. All brand new.
The third member is from Strange.  All new Pro nodular case, Eaton true trac differential, 31 spline with Motive Italian 3.50.1 ratio gears.

Test drive results:    Holy -oh no I used a word I shouldn't have- THIS THING MAKES ALOT OF NOISE!!!  It howls and skips noise up and down and is just freaking terrible.  And Strange says they have no warranty on noisiness!!!!   $1,700 for this third member and it makes noise like an old farm truck that somebody dug out of a pasture.  So, I will have to put the old aluminum 3.70 differential back in for the trip. It whines, but only about 10% of the noise this new POS makes.   Unbelievable.

And the harmonic vibration?   It changed a little. Maybe due to different gear ratio.  But still noticeable.  Hardly noticeable due to all my cussing and hollerin’ about the rear end noise.

I am going to start sawzalling exhaust system parts off the car until it goes away.  You know, maybe THAT might actually solve the complaining about the gear noise.

 
One more question. I was just looking at Strange's website and they offer the Motive gear set that you have and a Strange gear set.  Did your specifically order the Motive gears instead of the Strange gears?  I "think" I have Strange gears, but need to find my paperwork and double check.

 

3/08/2020 11:23 AM  #14


Re: Installing 9” in my 66

Sorry to hear that bit of news Steve. Once it's removed checking the back lash, contact mesh patterns and clearences should be easy enough. I hope they did not use a crush sleeve instead of shims. I hate those things.
My  3.25-1 8" Motive gears  had  very good  machined surfaces and are quiet.
 


Good work ain't cheap, Cheap work ain't good!   Simple Man
 

3/08/2020 12:02 PM  #15


Re: Installing 9” in my 66

Couple questions:
1. Did you do the heat/cool cycles? They are important for honing the gears together and work hardening the surface of the gears. (Of course the initial setup has to be correct)
2. Do you have the 500 break in miles on it yet? If not you may be panicing prematurely. We all know that it is important to panic at exactly the correct time to get the maximum anxiety from the event.

 

3/08/2020 12:39 PM  #16


Re: Installing 9” in my 66

Hornman wrote:

Couple questions:
1. Did you do the heat/cool cycles? They are important for honing the gears together and work hardening the surface of the gears. (Of course the initial setup has to be correct)
2. Do you have the 500 break in miles on it yet? If not you may be panicing prematurely. We all know that it is important to panic at exactly the correct time to get the maximum anxiety from the event.

Thank you Ron...still LOL.


"you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
 

3/08/2020 3:30 PM  #17


Re: Installing 9” in my 66

Chaplin wrote:

MS wrote:

The housing and axles are from Currie. All brand new.
The third member is from Strange.  All new Pro nodular case, Eaton true trac differential, 31 spline with Motive Italian 3.50.1 ratio gears.

Test drive results:    Holy -oh no I used a word I shouldn't have- THIS THING MAKES ALOT OF NOISE!!!  It howls and skips noise up and down and is just freaking terrible.  And Strange says they have no warranty on noisiness!!!!   $1,700 for this third member and it makes noise like an old farm truck that somebody dug out of a pasture.  So, I will have to put the old aluminum 3.70 differential back in for the trip. It whines, but only about 10% of the noise this new POS makes.   Unbelievable.

And the harmonic vibration?   It changed a little. Maybe due to different gear ratio.  But still noticeable.  Hardly noticeable due to all my cussing and hollerin’ about the rear end noise.

I am going to start sawzalling exhaust system parts off the car until it goes away.  You know, maybe THAT might actually solve the complaining about the gear noise.

 
One more question. I was just looking at Strange's website and they offer the Motive gear set that you have and a Strange gear set.  Did your specifically order the Motive gears instead of the Strange gears?  I "think" I have Strange gears, but need to find my paperwork and double check.

 
I told them I wanted the gears that would be the quietest possible, since that was my entire reason for the change. He said to go with Motive.


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
     Thread Starter
 

3/08/2020 3:36 PM  #18


Re: Installing 9” in my 66

Hornman wrote:

Couple questions:
1. Did you do the heat/cool cycles? They are important for honing the gears together and work hardening the surface of the gears. (Of course the initial setup has to be correct)
2. Do you have the 500 break in miles on it yet? If not you may be panicing prematurely. We all know that it is important to panic at exactly the correct time to get the maximum anxiety from the event.

 
First 50 mile trip with cool down afterwards. Have driven about another fifty miles. They sound worse.  Never heard gears sound so bad.  My father in law once drove a dodge pickup from San Antonio to Dallas for me to work on.  When I pulled the differential, one of the main cap bolts FELL INTO THE DRAIN PAN. That differential did not make as much noise as mine does.

I don’t have time to mess around getting madder and madder in order to log 500 miles. The old 3.70 is going back in.

If you bought a new Ford with a 9” rear in it and it howled and whined on the way home, would you be willing to “put some miles on it ... it will be fine “?


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
     Thread Starter
 

3/08/2020 3:44 PM  #19


Re: Installing 9” in my 66

MS wrote:

Chaplin wrote:

MS wrote:

The housing and axles are from Currie. All brand new.
The third member is from Strange.  All new Pro nodular case, Eaton true trac differential, 31 spline with Motive Italian 3.50.1 ratio gears.

Test drive results:    Holy -oh no I used a word I shouldn't have- THIS THING MAKES ALOT OF NOISE!!!  It howls and skips noise up and down and is just freaking terrible.  And Strange says they have no warranty on noisiness!!!!   $1,700 for this third member and it makes noise like an old farm truck that somebody dug out of a pasture.  So, I will have to put the old aluminum 3.70 differential back in for the trip. It whines, but only about 10% of the noise this new POS makes.   Unbelievable.

And the harmonic vibration?   It changed a little. Maybe due to different gear ratio.  But still noticeable.  Hardly noticeable due to all my cussing and hollerin’ about the rear end noise.

I am going to start sawzalling exhaust system parts off the car until it goes away.  You know, maybe THAT might actually solve the complaining about the gear noise.

 
One more question. I was just looking at Strange's website and they offer the Motive gear set that you have and a Strange gear set.  Did your specifically order the Motive gears instead of the Strange gears?  I "think" I have Strange gears, but need to find my paperwork and double check.

 
I told them I wanted the gears that would be the quietest possible, since that was my entire reason for the change. He said to go with Motive.

 

Oh boy, that doesn't bode well for me. 😬

 

3/08/2020 3:51 PM  #20


Re: Installing 9” in my 66

I'd be looking for a set of genuine FORD gears .... even secondhand in good condition.


"Those telephone poles were like a picket fence"
 

3/08/2020 6:57 PM  #21


Re: Installing 9” in my 66

BUmmer!   I/we were hoping THIS......was gonna be the 'silver-bullet'!
6sal6


Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
 

3/08/2020 10:26 PM  #22


Re: Installing 9” in my 66

MS wrote:

Hornman wrote:

Couple questions:
1. Did you do the heat/cool cycles? They are important for honing the gears together and work hardening the surface of the gears. (Of course the initial setup has to be correct)
2. Do you have the 500 break in miles on it yet? If not you may be panicing prematurely. We all know that it is important to panic at exactly the correct time to get the maximum anxiety from the event.

 
First 50 mile trip with cool down afterwards. Have driven about another fifty miles. They sound worse. Never heard gears sound so bad. My father in law once drove a dodge pickup from San Antonio to Dallas for me to work on. When I pulled the differential, one of the main cap bolts FELL INTO THE DRAIN PAN. That differential did not make as much noise as mine does.

I don’t have time to mess around getting madder and madder in order to log 500 miles. The old 3.70 is going back in.

If you bought a new Ford with a 9” rear in it and it howled and whined on the way home, would you be willing to “put some miles on it ... it will be fine “?

Yes.

 

3/09/2020 6:54 AM  #23


Re: Installing 9” in my 66

Motive is what in the 67. I'm trying remember if they are the ones that used the same part #, but one set ended in M, the other with L, or something like that. Were still on the road, so I can't check to be sure.

 

3/09/2020 10:20 AM  #24


Re: Installing 9” in my 66

If you bought a new Ford with a 9” rear in it and it howled and whined on the way home, would you be willing to “put some miles on it ... it will be fine
 
Not a chance in hell!


Good work ain't cheap, Cheap work ain't good!   Simple Man
 

3/09/2020 10:52 AM  #25


Re: Installing 9” in my 66

Hornman wrote:

MS wrote:

Hornman wrote:

Couple questions:
1. Did you do the heat/cool cycles? They are important for honing the gears together and work hardening the surface of the gears. (Of course the initial setup has to be correct)
2. Do you have the 500 break in miles on it yet? If not you may be panicing prematurely. We all know that it is important to panic at exactly the correct time to get the maximum anxiety from the event.

 
First 50 mile trip with cool down afterwards. Have driven about another fifty miles. They sound worse. Never heard gears sound so bad. My father in law once drove a dodge pickup from San Antonio to Dallas for me to work on. When I pulled the differential, one of the main cap bolts FELL INTO THE DRAIN PAN. That differential did not make as much noise as mine does.

I don’t have time to mess around getting madder and madder in order to log 500 miles. The old 3.70 is going back in.

If you bought a new Ford with a 9” rear in it and it howled and whined on the way home, would you be willing to “put some miles on it ... it will be fine “?

Yes.

I’m calling bulls$41+ on your answer, Hornman


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
     Thread Starter
 

Board footera


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