9 inch third member gear setup
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Car: 1991 Camaro RS
Engine: 355
Transmission: 700-R4
Axle/Gears: 4.10
9 inch third member gear setup
As the title suggests I need some help setting up a 9 inch third member. It's complete right but I'm going to swap the open carrier for a trac-loc unit. I'm wondering what needs to be set up. I've read that the pinion depth should be ok which makes sense as it is not touched when removing the ring gear but what type of adjustment need to be made to ensure proper gear mesh and backlash? Any help would be great especially pictures. Thanks in advance.
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Car: A Portly 85 Z28
Engine: 4.530 X 4.250 BBC
Transmission: under rated for this application
Axle/Gears: also under rated
Re: 9 inch third member gear setup
The 9 inch uses threaded caps, once you replace the gear onto the new carrier, you`ll need set the back lash, using the left threaded collar tighten it until you get 8-10 thou of back lash. You will need to set up a dial indicator to measure this, marking compound on the gear teeth will show you the contact pattern also. I personally have Scott at driveline solutions do my gear axle work, he is on the eastside by 696 and 94
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Car: 1991 Camaro RS
Engine: 355
Transmission: 700-R4
Axle/Gears: 4.10
Re: 9 inch third member gear setup
How is the backlash measured? Or I should say, what is backlash? The distance between what and what?
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Car: A Portly 85 Z28
Engine: 4.530 X 4.250 BBC
Transmission: under rated for this application
Axle/Gears: also under rated
Re: 9 inch third member gear setup
it`s measured with a dial indicator and it is the clearance between the pinion and ring teeth
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Car: 1991 Camaro RS
Engine: 355
Transmission: 700-R4
Axle/Gears: 4.10
Re: 9 inch third member gear setup
Did some research last night and that's what I came up with. Another question, is there a special tool needed to turn the caps? It looks like something with teeth or pegs that would fit into all or some of the holes on the caps may work but I'd like to do it the right way before I go making a tool.
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Car: 88 Trans-Am
Engine: 406 SBC
Re: 9 inch third member gear setup
Snap-On makes a universal spanner wrench that will work for this:
http://buy1.snapon.com/catalog/item....re&dir=catalog
Also before you disassemble the third member measure the existing backlash and write it down. Mark the ring and pinion gears where they were meshed when you measured. After you reassemble set the backlash to the same as it was with the gears in the same spot. This will keep the gear contact pattern in the same place which is what you want. Make sure when you are measuring the backlash that the pinion gear does not turn at all if you have to strap the housing down with the yoke flat on the bench.
Hope this helps.
http://buy1.snapon.com/catalog/item....re&dir=catalog
Also before you disassemble the third member measure the existing backlash and write it down. Mark the ring and pinion gears where they were meshed when you measured. After you reassemble set the backlash to the same as it was with the gears in the same spot. This will keep the gear contact pattern in the same place which is what you want. Make sure when you are measuring the backlash that the pinion gear does not turn at all if you have to strap the housing down with the yoke flat on the bench.
Hope this helps.
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Car: 88 Trans-Am
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Re: 9 inch third member gear setup
After my post I found this on youtube, may help you also:
http://www.youtube.com/watch?v=bSCUck4M6W4
http://www.youtube.com/watch?v=bSCUck4M6W4
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Car: 1991 Camaro RS
Engine: 355
Transmission: 700-R4
Axle/Gears: 4.10
Re: 9 inch third member gear setup
xpndbl3 - Sorry for the bumps, really wanted to get to the track this weekend.
88 - Ahh yes, spanner wrench! Don't know why I couldn't think of that.
greezemonkey - Thank you for the input. I followed your instuctions and finished the job. Nice wear patternd and no whining.
Slight problem though. Still no posi!! This is a posi carrier for sure this time so I assume the clutches are fried. Any sugestions on how to proceed?
88 - Ahh yes, spanner wrench! Don't know why I couldn't think of that.
greezemonkey - Thank you for the input. I followed your instuctions and finished the job. Nice wear patternd and no whining.
Slight problem though. Still no posi!! This is a posi carrier for sure this time so I assume the clutches are fried. Any sugestions on how to proceed?
#13
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Car: 1991 Camaro RS
Engine: 355
Transmission: 700-R4
Axle/Gears: 4.10
Re: 9 inch third member gear setup
88 - Just watched that video. Perfect!!! Again, I didn't even think to look on YouTube.
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Car: A Portly 85 Z28
Engine: 4.530 X 4.250 BBC
Transmission: under rated for this application
Axle/Gears: also under rated
Re: 9 inch third member gear setup
trac loc`s are rebuildable, i know I have seen the clutches for sale.
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Car: 1991 Camaro RS
Engine: 355
Transmission: 700-R4
Axle/Gears: 4.10
Re: 9 inch third member gear setup
Yup, I think I'll pick up a clutch set from ebay this week and see what I get. I'll keep the thread updated in case anybody else needs to complete the same task.
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