Replacing the Center section on a 9 inch

[Cipher43]

Hello all. I picked up a new carrier that is a 325 posi and want to switch it out soon but I have never torn into a 9 inch before. What all am i gonna need to do this? Any gaskets or anything?
Thanks

[sargentrs]

If its in good condition all you need is a new housing gaskets n some gear oil. You'll have to take your brake lines loose at the wheel so grab some brake fluid too. You should bleed the brakes when you're done.

[70shortwide]

If its in good condition all you need is a new housing gaskets n some gear oil. You'll have to take your brake lines loose at the wheel so grab some brake fluid too. You should bleed the brakes when you're done.

Why do you need to take the brake lines loose? heres how I do it:

Jack the rear up (use jackstands)

pull wheels and brake drums

unbolt driveline

Pull the 4 (each side) axle retaing nuts (you should be able to get a socket through the hole that is between your studs on the end of your axle shaft, turn the axle to get it to line up with each bolt)

slide axles out about 6" (now would be a good time to just slide it clear out, check it for any abnormal wear, extreme twisting etc.)

pull the nuts from the front of the housing that hole the 3rd member in. there may be some copper washers on the studs if it hasnt been apart before. you'll need to take these off, I usually use a flat head screwdriver and a pair of needlenose pliers. Start at the bottom and let it drain before you pull the last few from the top.

once you have the washers of the center section with come right out. be careful, as its pretty heavy if your not expecting it to fall out.

reverse steps to put it back in, I use "the Right Stuff" silicone instead of the gasket. Youd wont need the copper washers with silicone.

[sargentrs]

Duh! My bad. I didn't even think to unbolt the axle from the brake backing plate. My bad.

[ultraranger]

I would caution against sliding the axles out just enough to clear the 3rd member. Leaving the weight of the axles resting on the axle seals can cause them to fail prematurely. It would be best to take the axles completely out of the housing and set them aside while you swap out 3rd members. --hold up on the axles as they're being removed (or being installed) so that the full weight of them isn't dragging across the axle seals.

To remove the (10) 3rd member-to-housing nuts, you will need a 9/16" socket and a 9/16" boxed end wrench. (you will not be able to get a socket onto the extreme, bottom two studs/nuts on the 3rd member. This is where you will have to use the 9/16" end wrench).

You will need a 3rd member-to-housing gasket, (3) bottles of gear oil, (1) 4oz bottle of friction modifier. --if the pinion seal is leaking, changing it out takes some knowledge of what you are doing. It's not just a simple matter of popping the flange off, removing the old seal, putting the new seal in, sliding the flange back on an then tightening the begeezus out of it. There is a crush sleeve, inside, on the pinion that has to be tightened back to its original setting (within close proximity, anyway). Not enough tension and things will come loose. Too much tension and you will further compress the sleeve, which is going to change the preload setting and the engagement of the pinion in relation to the ring gear. --whatever you do, DON'T use an impact on the large input driving pinion nut to remove or install it! (doing so can damage the pinion bearings and/or races).

If the axle bearings have been in place a long time, this is a good time to replace them. A simple check to see if the bearings are good is to place your thumb against the side of the bearing and give it a swift spinning motion. If the bearing spins for more than 1-1/2 revolutions, replace it.

This would also be a prime time to install new axle seals. If you do, be sure to coat the rubber portion of the seals with some gear oil before reinstalling the axles.

[ultraranger]

I went through the 9-inch rear end in my '69 Ranger about a year and a half a go. Here are some part numbers from O'Reilly auto Parts:

1. 3rd member-to-housing gasket; Fel-Pro RDS 55074, $4.74

2. Rear Wheel (axle) seal [you will need (2)]; MPS 51098, $8.99 ea.

3. Pinion seal [if you decide to change it]; NAT 7044NA, $16.99

4. Axle bearing [2 reqd.]; NAT 514003, $41.99 ea.

[Cipher43]

Thanks guys I will check it out this weekend I hope.

[motzingg]

This is a great thread, sorry for the threadjack but i was wondering

given a 68 with about 80k miles, some oil in the rear end but not enough and its kinda dirty.

Should i assume that my bearings, seals, etc are all shot and need replacing before i can go long distance reliably, or can i assume that if it is not making noise or puking oil, things are kosher?

I'm planning on driving this truck from N.C to Texas in a couple months, hauling a good sized trailer. Not the craziest thing i've done by a long shot, but i'd rather avoid catastrophic failure if i can.

[70shortwide]

This is a great thread, sorry for the threadjack but i was wondering

given a 68 with about 80k miles, some oil in the rear end but not enough and its kinda dirty.

Should i assume that my bearings, seals, etc are all shot and need replacing before i can go long distance reliably, or can i assume that if it is not making noise or puking oil, things are kosher?

I'm planning on driving this truck from N.C to Texas in a couple months, hauling a good sized trailer. Not the craziest thing i've done by a long shot, but i'd rather avoid catastrophic failure if i can.

At the very least I would change the oil... And definately get a AAA membership.