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.

 

bump

 

Bump

 

umm..... Bump?

 

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

 

How is the backlash measured? Or I should say, what is backlash? The distance between what and what?

 

it`s measured with a dial indicator and it is the clearance between the pinion and ring teeth

 

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.

 

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.

 

sounds to me like you need to have someone local show you how to set them up or just bite the bullet and pay a shop to do it.


PS You don't need to bump the thread every 4-6 hours to get an answer.

 

After my post I found this on youtube, may help you also:

http://www.youtube.com/watch?v=bSCUck4M6W4

 

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 - Just watched that video. Perfect!!! Again, I didn't even think to look on YouTube.

 

trac loc`s are rebuildable, i know I have seen the clutches for sale.

 

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.