What tools will I need?

[farside847]

I am planning on replacing my rear gear ratio from a 3.73 to a 3.08. I have seen
lots of guys selling the gearsets on the parts forum. But I have never done
this before. What kind of tools will I need? Will I need to press-on anything
or will I need any special removal tool?

I just dont want to get half way through, then figure out I needed a
blue pair of left handed scissors to finish the job...

thanks!

[pjmoreland]

The pinion gear bearing is a bit of a chore to get off, but if you are installing a new bearing, then you don't have to worry about it.

[cdowns]

i hope you realize that you're going to need a different carrier for the 308gearset. you'll also need a dial indicator to set the gears up

[farside847]

Originally Posted by cdowns

i hope you realize that you're going to need a different carrier for the 308gearset. you'll also need a dial indicator to set the gears up

(blank look)

Ummmm. This was what I was afraid of. Seeing as I dont even know what a
carrier is, nor what a dial indicator even looks like.

Im not afraid of doing something new and learning something along the way,
but to you know of any "how-to" guides that might help me out? I hate to
sound like such an amateur....

[JimKshortstep4x4]

I would suggest that you enlist someone to help you that has done a gear set change before. If the gears are not properly meshed you can end up with noisy rear end or the rear end will destroy itself.

Jim

[Fred T]

Do you have the factory service manual? If not, it will become the best tool in your toolbox. You can buy a reprint from the on-line parts dealers.

Sounds like you will be over your head on this. I would recommend getting the carrier assembly (pumpkin) out of another truck. That way you don't have to worry about setting up the gears. It will involve only removing the cover, pulling the axles out and changing the carrier. I would also replace the axle seals while you have it apart.

[67chevemall]

Heres my email form a board member! He rocks!

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Quote:
Originally Posted by 67chevemall
It is a stock 12 bolt 3:73 that works great
But the top end is no good.
I would just swap the gears and change the
oil?? What other parts, tools are involved?

What on earth does "the carrier break is 3:42's"
mean?
Cheers and thanks!
BC



The carriers are what the ring gear bolts to. There are different carriers for different gears. There is one for 2:73-2:76, 2:76-3:42,3:42-3:73, and 3:73-up. That's what I mean about breaks.

The gears are not as easy to do as change the gears, chaneg the oil and go. You actually have to "setup" the gears so that the have good connection between the pinion and ring gear. If you were to just take yours off and put mine on and throw them back in you would probably get a noisy diff or possible a broken pinion or ring gear or even a carrier. If you take your parts to a shop they shouldn't charge to much to put it in.

Let me know what you want to do.

Quote:
Originally Posted by 67chevemall
So the 3:08's use a different carrier
then my 3:73's? I need 3:08 gears and carrier.
Is it good to "install everything then get it set up.
Or just take all the parts to a good shop?
Cheers
BC

Yes you need a differnt carrier for your 3.08 gears than what you have. I have both the gears and carrier if you want both. And no You need to take the parts to someone to install them for you. it won't work fo you to take it already installed cause they have to take them out again.
__________________
They came out of my 73. The gears are nice and smooth, no grooves in them so yes they will work fine in a Daily driven truck


Quote:
Originally Posted by 67chevemall
One last ? , What year trucks have the same 12 bolt
rear ends? 67 to ?
Cheers,

67-81.


Hope that helps
Cheers

[boraxman]

Personally I wouldnt attempt this myself. This is a job that should be done by someone w/ experince. Im a decent back-yard mech. and this is one job I wouldnt do unless I was in the trial and error learning mode.

[flip66]

You can get the dial indicator and stand for it at sears in the wood tool department about 85.00 you will need crush sleeve and shims and gear marking compound I got mine a GM dealer. There are allot of articles on the web about how to do it

[southern parts]

It may be cheaper and easier to find a good used 3.07 rearend and replace the whole thing. Around hear (Atlanta) they sell for about $225.00-$250.00 sometimes less if you can find one at a pull-a-part or pick-n-pull type junkyard.

[HugrOrang71]

Originally Posted by boraxman

Personally I wouldnt attempt this myself. This is a job that should be done by someone w/ experince. Im a decent back-yard mech. and this is one job I wouldnt do unless I was in the trial and error learning mode.

I agree. I worked for a company that builds custom differentials. Gear setup is a time consuming and tedious process. I have spent hours trying to get the perfect pattern, only to end up back where I started. Consider that the difference between a quiet running gearset that will last a couple 100K miles and a noisy one that may not see 20K can be .001".
The money you may save by doing it yourself may cost you double when you have to get it done again later.

[farside847]

Thanks guys, I hear ya. I will call my mechanic and ask him to refer me to a good
gear shop to do this for me.

[Lemield]

Originally Posted by farside847

Thanks guys, I hear ya. I will call my mechanic and ask him to refer me to a good
gear shop to do this for me.

Hey farside847,

I was going to do the same thing with a new gearset and an Eaton posi unit for my CST. I know that I am capable of doing it but it is pretty specialized so I called around here in Denver and found a guy that sets them up for a living. He did a wonderful job and he was reasonable. Good Luck.