GM 12 bolt Rebuild

[67see10]

I'm getting ready to buy the parts to rebuild my rear end for my 67 c10 but I am unsure which posi unit to buy.

I want to run a Eaton Posi and 3.73 Richmond Gears but am not sure if it should be a 3 or 4 series carrier.

Eaton Posi Part Number ????
Richmond 3.73 Gears Part Number ????
Richmond Gear Differential Complete Kit 8.875" 12 Bolt part number 83-1018-1

[A1971Blazer]

Go here and run the Diff Wizard...it will give you the part numbers....then look at Jeg's or Summit for a better price...
https://www.randysworldwide.com/

[71meangreenc10]

I have rebuilt several 12 bolts and more on the future and unless you have a great history with Richmond Gears I would choose another brand. Lots of issues on the web and I ran into gear noise myself. 3.73 gears (regular) run a series 4 carrier.

Smitty

[A1971Blazer]

Originally Posted by 71meangreenc10

I have rebuilt several 12 bolts and more on the future and unless you have a great history with Richmond Gears I would choose another brand. Lots of issues on the web and I ran into gear noise myself. 3.73 gears (regular) run a series 4 carrier.

Smitty

I had never used a Richmond gear ring and pinion...but my buddy killed the ring gear and pinion on his '72 K/5......

He bought all the parts with the Richmond gear set and I installed it for him...it was a 3.08 and it went in perfectly....

I set the pinion depth to the dimension etched on the end and it patterned perfectly....
ran it in for a few minutes off the ground and drove it off...quiet as can be.....

again this was my first experience with Richmond...not plugging them.....just my 2¢

[67see10]

Originally Posted by 71meangreenc10

I have rebuilt several 12 bolts and more on the future and unless you have a great history with Richmond Gears I would choose another brand. Lots of issues on the web and I ran into gear noise myself. 3.73 gears (regular) run a series 4 carrier.

Smitty

I have no real experience with Richmond. What would you recommend?

[71meangreenc10]

I installed a set into a 12 bolt and from opening the box I started questioning the product. The compound markings from the factory were way more towards the toe side than I set up (not a racing application). I did get it exactly as they sent it with the BL at .008 that was scribbled on the gear set. All new bearings went in also. Started out great, no noise, broke it in all was good. After about 25 miles on it started getting noise on decel. Tore it apart and the outer pinion race grenaded itself. Replaced all bearings with Timken's and started making more noises and they were not consistent at all not same RPM's, speeds or gear selections.. Tore back apart, Timken's were perfect. Started digging and found that the gears are made in India and they are making them with a harder material and that they can make noise. Read a bunch of threads and found professionals with the same issues. Now I am not bashing Richmond Gears at all. The set I installed has over 2K on them and the guy is happy with it and drove it on a 1600 mile trip from AZ to TN with zero problems. I hate gear noises and that would drive me crazy driving it.

For me, I have used Motive Gears and I use Open Carriers and have had no problems or noises. I suggest doing a lot of research on the gear set you want to install and make phone calls to get to your comfort level. It is a lot of money to get an axle rebuilt and you want to ensure that it is to your satisfaction. Try looking at US Gear and TomsDifferentials.

Lastly,

Is the original poster installing the gears or having them installed?

Smitty

[Street Smart]

Yukon makes a good ring and pinion, easy to set up a good pattern and quiet. Always my first choice for a driven vehicle. I usually still go with Richmond in a car /truck that's raced. Be careful with a lot most of these companies are selling two different grade gears. Regular ones and a cheaper imported set.
Yukons install kits always come with Timken bearings and races.

[67see10]

Originally Posted by Street Smart

Yukon makes a good ring and pinion, easy to set up a good pattern and quiet. Always my first choice for a driven vehicle. I usually still go with Richmond in a car /truck that's raced. Be careful with a lot most of these companies are selling two different grade gears. Regular ones and a cheaper imported set.
Yukons install kits always come with Timken bearings and races.

Would you recommend using the Yukon dura drip post as well?

[67see10]

Originally Posted by 71meangreenc10

I installed a set into a 12 bolt and from opening the box I started questioning the product. The compound markings from the factory were way more towards the toe side than I set up (not a racing application). I did get it exactly as they sent it with the BL at .008 that was scribbled on the gear set. All new bearings went in also. Started out great, no noise, broke it in all was good. After about 25 miles on it started getting noise on decel. Tore it apart and the outer pinion race grenaded itself. Replaced all bearings with Timken's and started making more noises and they were not consistent at all not same RPM's, speeds or gear selections.. Tore back apart, Timken's were perfect. Started digging and found that the gears are made in India and they are making them with a harder material and that they can make noise. Read a bunch of threads and found professionals with the same issues. Now I am not bashing Richmond Gears at all. The set I installed has over 2K on them and the guy is happy with it and drove it on a 1600 mile trip from AZ to TN with zero problems. I hate gear noises and that would drive me crazy driving it.

For me, I have used Motive Gears and I use Open Carriers and have had no problems or noises. I suggest doing a lot of research on the gear set you want to install and make phone calls to get to your comfort level. It is a lot of money to get an axle rebuilt and you want to ensure that it is to your satisfaction. Try looking at US Gear and TomsDifferentials.

Lastly,

Is the original poster installing the gears or having them installed?

Smitty

No I am having someone install them

[Street Smart]

Originally Posted by 67see10

Would you recommend using the Yukon dura drip post as well?

I`ve never used one, I usually go with Eaton Differentials. Posi`s or their true tracs. True tracs are stronger and less expensive. I have an Auburn in my truck because I had a big credit with a company and saved a lot of cash. Been low 12`s with a good tire at over 4900 lbs, still holding up.

[swervins69]

The Yukon is the one I went with. Basically a Eaton clone. Yukon makes quality stuff.