lsd installation
Burning Brakes
Joined: Apr 2004
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From: Indiana
i would say you need to remove the tranny since you may have to check some tolerances and possibly adjust the ring and pinion backlash. also, i'm not sure if the diff will clear the chassis.
the tranny can be pulled in 3-5 hours depending on how hard it is to remove your exhaust. contrary to what the shop manuals say, one of the first steps should be to unbolt the drive axles.
the tranny can be pulled in 3-5 hours depending on how hard it is to remove your exhaust. contrary to what the shop manuals say, one of the first steps should be to unbolt the drive axles.
Under the Lift
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Joined: Mar 2002
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From: Buckeye, AZ
I haven't done this, but I have looked into doing it. Since you use the ring gear from your current diff, it should have the same backlash. The other issue is left to right alignment with shims, but many have found they pop the new diff in and check to find it is within spec.
It's tight, but I think the diff can come out of the case without dropping the tranny. It depends on the clearance between the diff case and the battery box, which varies from year to year. Measure it and measure the diff.
It's tight, but I think the diff can come out of the case without dropping the tranny. It depends on the clearance between the diff case and the battery box, which varies from year to year. Measure it and measure the diff.
Three Wheelin'
Joined: Nov 2003
Posts: 1,481
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From: Doylestown, PA
Bill hit the nail on the head. If your diff has 14 thou of backlash before you take it apart you don't want to put it back together and reduce the backlash to 10 thou if spec calls for a value between 8 and 16. It needs to stay at the value of the "original" setting. My numbers are purely hypothetical!
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Joined: Oct 2003
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From: Nova Scotia
Just installed a Trac-Lok posi carrier in my F150 this week, replacing the open diff ( yeah, it's not a Porsche .... but 'gears are gears', and it is a clutch pack type). Besides, this one gets to play in the snow .. 
As long as the pinion remains untouched and the same ring gear is retained, generally you only need measure the lash on the ring before disassembly. In this case, it was 12 thou, and is set by laterally shimming the carrier bearings ( which also is used to set the preload on these bearings, as the shims load the races, not the cone/inner race).
The new posi carrier was fitted with the ring and shimmed to a best of 11.5 thou .... close 'nuff, and following the principle FBIII noted. If your diff was happy before, repeat the setting - you can tell by the ring/pinion contact pattern. Maybe some of this will be applicable to the LSD.
PS - if used, the malicious odour of friction modifier makes gear oil seem like Chanel #5
As long as the pinion remains untouched and the same ring gear is retained, generally you only need measure the lash on the ring before disassembly. In this case, it was 12 thou, and is set by laterally shimming the carrier bearings ( which also is used to set the preload on these bearings, as the shims load the races, not the cone/inner race).
The new posi carrier was fitted with the ring and shimmed to a best of 11.5 thou .... close 'nuff, and following the principle FBIII noted. If your diff was happy before, repeat the setting - you can tell by the ring/pinion contact pattern. Maybe some of this will be applicable to the LSD.
PS - if used, the malicious odour of friction modifier makes gear oil seem like Chanel #5
Addict
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Joined: Jun 2003
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From: Helsinki, Finland
See WSM page 39-220 for table which explains what needs to be done when parts are changed. In case of differential it only asks for S1 and S2 adjustments. Still I would check backlash also while at it.