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9" locker in 8" rear?

  • Thread starter Thread starter 5.0n66
  • Start date Start date Jun 17, 2004

5.0n66

New Member
Nov 19, 2002
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New Holland (Lancaster, PA)
Jun 17, 2004
#1
  • Jun 17, 2004
  • #1
if anybody happens to know..... would a 28spline locker (lock-right or ez-locker.."drop in" types) labeled for a 9" rear fit an 8" axle? the splines should be the same I guess the questionmark is on the width of the carrier. be especially nice if it does so I can use it for the 9" i'll end up getting after my 8" is shredded by my (as yet untested) 5.0 Twin Turbo setup
 

ratio411

Founding Member
Apr 21, 2002
3,870
73
109
Pensacola FL
Jun 17, 2004
#2
  • Jun 17, 2004
  • #2
It is possible for sure.
I know that mini-spools interchange. They replace the spider gears. So it might work with something else that replaces the spiders.
I am not interested in doing this, but I sure am curious if anyone knows. It's the kind of useless knowledge I love to fill my brain with.
Dave
 

6Stang7

New Member
Jun 1, 2003
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Livermore, CA
Jun 17, 2004
#3
  • Jun 17, 2004
  • #3
If it is an esay locker and it says 9" on the box, then yes it will cause it is the SAME EXCAIT THING as the 8". However, I would stay away from the EZ lockers. They will work fine and danddy in a 9" as the 9" has two pinion shafts (preventing side to side and up and down movement of the clutches). However, the 8" only has one, so that means that the locker's clutchs can move side to side (or up and down) causing them to not properly mess with the side gears and that will cause you to not get any power to the wheels. They do work, but because of this poor design, I don't trust them. How do I know this? I had one that did the very same thing. I spent $283 and all I gained was and extra dissassembling of my diff and drive back to the diff shop to have it removed (yes, it was PROFESSIONALLY installed). Posi isn't something you need, it is something you want. So I suggest that you save up the extra $$$ and get LSD unit. Trust me.
 
F

ForceFed70

That's why they call it "dope"
Founding Member
Dec 6, 1999
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69
BC Canada
Jun 17, 2004
#4
  • Jun 17, 2004
  • #4
Since when does a locker have clutches?

I was under the impression that the EZ locker used a pin-type locking system.
 

SadbutTrue

Founding Member
May 1, 2002
2,390
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49
Granada Hills, California
Jun 17, 2004
#5
  • Jun 17, 2004
  • #5
i just posted something similar, but mine is a bit more general... will a 9 inch third member work in an 8 inch housing, and is it very disadvantageous to do so? (In any way, really) It seems like a cheap way to get a posi that works nicely.
 
3

3spd on floor

Founding Member
Aug 13, 2002
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Acworth, GA
Jun 17, 2004
#6
  • Jun 17, 2004
  • #6
sadbuttrue - no, you cannot use a 9inch center section in an 8inch rear. some of the trac-lok parts are interchangable, but not the whole unit.
 

Zooted_plus

New Member
Jan 14, 2003
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Dublin, CA
Jun 17, 2004
#7
  • Jun 17, 2004
  • #7
3spd on floor said:
sadbuttrue - no, you cannot use a 9inch center section in an 8inch rear. some of the trac-lok parts are interchangable, but not the whole unit.
Click to expand...


There's a guy in Ohio who takes 8" axle housings and cuts the center out, welds in a 9"... so you can drop a 9" 3rd member with 28 spline axles. If anyone wants more info on how to contact him for pricing or what not, pm me.
 

ratio411

Founding Member
Apr 21, 2002
3,870
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109
Pensacola FL
Jun 17, 2004
#8
  • Jun 17, 2004
  • #8
Zooted_plus said:
There's a guy in Ohio who takes 8" axle housings and cuts the center out, welds in a 9"... so you can drop a 9" 3rd member with 28 spline axles. If anyone wants more info on how to contact him for pricing or what not, pm me.
Click to expand...
I was told by a pro that does narrowing and such that you should NEVER cut/weld on the tubes further away from the ends than you intend to remove.
In other words, cutting the tubes off the pumkin then welding them back is a big no-no. I don't know his reasoning for this, he was insistent that the resulting housing would be weak and/or break parts.
I know because I brought him a 9" housing pumpkin with the tubes cut totally off, so he could put it into my 8" rear just like you describe.
Like I said, I don't know why this is the case...
If anyone can assure me otherwise, I still have the 9" center, I would do this. It seems like it would be a sufficient mod to run behind a 306.
Dave
 

zookeeper

Founding Member
Aug 25, 2001
3,415
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109
Rogue River, Oregon
Jun 17, 2004
#9
  • Jun 17, 2004
  • #9
Since pretty much 90% of all 9 inches out there are 28 splines, and they interchange with 8 inch 28 splines, I don't see the need to butcher 2 perfectly good housings just to use 28 spline axles. But each his own...
 
F

Fostang

Founding Member
May 8, 2002
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Stockton, Ca
Jun 18, 2004
#10
  • Jun 18, 2004
  • #10
6Stang7 said:
If it is an esay locker and it says 9" on the box, then yes it will cause it is the SAME EXCAIT THING as the 8". However, I would stay away from the EZ lockers. They will work fine and danddy in a 9" as the 9" has two pinion shafts (preventing side to side and up and down movement of the clutches). However, the 8" only has one, so that means that the locker's clutchs can move side to side (or up and down) causing them to not properly mess with the side gears and that will cause you to not get any power to the wheels. They do work, but because of this poor design, I don't trust them. How do I know this? I had one that did the very same thing. I spent $283 and all I gained was and extra dissassembling of my diff and drive back to the diff shop to have it removed (yes, it was PROFESSIONALLY installed). Posi isn't something you need, it is something you want. So I suggest that you save up the extra $$$ and get LSD unit. Trust me.
Click to expand...


Yeah that sucked for you. screw ez lockers.

How are your 4.11's working?

When will it be time for the LSD??
 
F

Fostang

Founding Member
May 8, 2002
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Stockton, Ca
Jun 18, 2004
#11
  • Jun 18, 2004
  • #11
Zooted_plus said:
There's a guy in Ohio who takes 8" axle housings and cuts the center out, welds in a 9"... so you can drop a 9" 3rd member with 28 spline axles. If anyone wants more info on how to contact him for pricing or what not, pm me.
Click to expand...


We do that here in stockton $200. $120 to narrow a 9"
 
F

Fostang

Founding Member
May 8, 2002
1,400
0
36
Stockton, Ca
Jun 18, 2004
#12
  • Jun 18, 2004
  • #12
ratio411 said:
I was told by a pro that does narrowing and such that you should NEVER cut/weld on the tubes further away from the ends than you intend to remove.
In other words, cutting the tubes off the pumkin then welding them back is a big no-no. I don't know his reasoning for this, he was insistent that the resulting housing would be weak and/or break parts.
I know because I brought him a 9" housing pumpkin with the tubes cut totally off, so he could put it into my 8" rear just like you describe.
Like I said, I don't know why this is the case...
If anyone can assure me otherwise, I still have the 9" center, I would do this. It seems like it would be a sufficient mod to run behind a 306.
Dave
Click to expand...

If you don't know what your doing yes it's a bad idea but you do know that the tubes are supposto slide in to the center section and then be welded on.

You never simply put metal to metal together and weld for a rear always overlap(slide in).
 
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