big gear head

Yea, this will be the 36 eliment sprag, like the heavy duty TH400 piece. The transmission is still together, but there isn't much doubt about what went wrong. This was a customer's '70 Chevy truck with a 383. I built the rear end, not the transmission. I was test driving it when it broke. This isn't the first time that this has happened to me. I work on the rear end and then break the transmission. At least the rear end is good.

Yep, second gear roller clutch. It's being replaced with a dog leg sprag.

Just busted 2nd gear with 470 torque and 430 HP and street tires shifting at 6000.

I can set you up with one. Send me an email if you are interested. Just be sure that you understand that the spacer is not the best way to go. Here is what happens if you push it too hard with the spacer. Notice all of the ring gear bolts are broke.

The Camaro rear end is set up for leaf springs. Your Monte Carlo has a coil spring suspension. You can not use a Camaro rear end in your Monte Carlo with the stock suspension. You would have to use ladder bars, 4 link or some other after market suspension to put the Camaro rear end in it.

If you have a vibration and a pinion seal leak then you need to look at the pinion bearings. Most pinion seal leaks come from worn out pinion bearings. If you have any movement in the pinion besides rotational movement then you have a bearing problem. Hold the yoke and see if you can move it up and down or in and out. If it moves even the slightest amount then you need to replace the bearings. If it turns out that the bearings are good then you can replace the seal without going into the rear end any farther. Remove the nut and the yoke. Knock out the seal and clean the area in the end of the housing where the seal goes. You didn't mention which rear end you have, so I'm assuming it is a 12 bolt. The new seals that are made for the 12 bolt are too deep. When you drive it in you need to leave it out about 1/16 to 1/8 inch from being bottomed out. Use RTV sealant around the outside of the seal before you drive it in. Use some grease on the rubber lip of the seal before installing the yoke. Smear some RTV sealant into the splines of the yoke before you put it on so that oil doesn't seap out through them. Put the nut on with red Loctite and torque it to 150 foot pounds. This should have you fixed up. If you find that the bearings are bad then there is a lot more to fixing that. You might want to take it to a shop that has experience with rear ends. The bearing preload will have to be set and the contact pattern needs to be checked after it is assembled.

All big block cars up to '72 got the 12 bolt. After that they got the 8.5 10 bolt. No big block Chevy cars got the 8.2 10 bolt.

The '71 Caprice rear end will be the 8.5 10 bolt. The posi and gears from that rear end will fit in any 8.5 10 bolt up to '89. Any '71 to '81 Camaro or Firebird can use those parts, so selling them would be easy. Go to www.nastyz28.com and list them for sale. You will sell them quick.

No, it wont fit. The suspension is completely different and it is too wide.

You can get 3.08 to 5.13 for the 8.2 10 bolt, and they all fit the 3 series differential.

Most of the '71 and '72 Monte Carlos had the 8.2 10 bolt, but there were a few that got the 8.5 10 bolt. The 8.2 has a 1 1/8 pinion nut and 3/8 ring gear bolts with 9/16 heads. The 8.5 has a 1 1/4 pinion nut and 7/16 ring gear bolts with 3/4 heads and left hand threads. If you have the 8.2 with 2.73 gears then you will need a 3 series differential. This would be a good time to get a new Eaton 3 series posi. If you have the 8.5 rear end then you can use the 3.73 on the same differential as the 2.73.

Did it have a TH350 or a TH400? If it was a TH350 then it will be exactly the same. If it was a TH400 then it might be different. I know that the Camaros used a different cross member for the TH400.

It might be an easy check, but not accurate. If it is a posi with worn clutches then it will turn easy and the other wheel will turn in the opposite direction. If it is not a posi, but has been abused (one wheel burnouts) or the housing is bent a little then it will be hard to turn and the other wheel will turn in the same direction. There is ONLY ONE way to be sure. That is to remove the cover and look at it.

Contact Wally at wally@muncie4speed.com

I sent you an email.

Most Richmond gears that make noise are simply set up wrong. Either the backlash or pinion depth is not correct. I have had a few problems with Richmond gears, but I can't say that they have more problems than any other manufacturer. I use mostly Motive Gear and US Gear.

I just shipped some 12 bolt parts to Calgary last week. Send me an email and I'll send you some prices. I don't think I have a used set of gears, but I have the installation kit on the shelf.

I'm not familiar with that code. Does it have 10 or 12 bolts in the cover?

I've been installing Moser axles for many years now and I've not seen one fail yet. The Mark Williams, Strange and other racing axles don't seem to hold up on the street, but these companys have come out with some new axles that are suppose to be street worthy. I just like the Moser axles. As for Dana, they are an OEM manufacturer. You can also get axles for your Chevy that use the 9 inch Ford axle bearings and eliminate the c clips. You have to weld on special housing ends to use them, but you can retain the Chevy brakes. These are much better than the c clip eliminators.

These guys are right, the Buick rear end is probably the 8.5 10 bolt and you Monte Carlo rear end is probably the 8.2 10 bolt. You can not take the parts out of the 8.5 and put them in the 8.2. The upper controll arm mounts were changed in '73 to a 90 degree angle. The '72 and earlier rear ends had les than a 90 degree angle, so changing the brackets isn't going to work either. You could try something like ladder bars. As for the axles, if the Buick has the 5 on 5 bolt pattern then it probably also has the larger truck axle bearings, so swaping the axles won't work either. Don't mean to ruin your good mood, but I'd hate to see you go to a lot of trouble for something that won't work. There are some 8.5 rear ends that were installed in the '72 Chevelles and other mid size GM cars. If you can find one of them you could swap the internal parts and use it. If not then sell the gears and posi to someone with a second gen Camaro.

The Eaton posi is the smoothest operating posi for GM rear ends, and it is rebuildable. It might cost a bit more, but it is worth it. The Lock Right by Power Trax is easy to install, but it does make some noise. I have had one in my 4X4 daily driver for about 8 1/2 years and it works great, just noisy and jerky. Many people have had problems with the newer No-Slip by Power Trax. I don't recommend it. To install the Eaton you will have to measure the backlash before you remove the original differential and set it to the same value with the new Eaton. This is done with shims. You will need a dial indicator with a magnetic base to make the measurements. You will also need to know which rear end you have in your car.

The 12 bolt uses a 2 series differential for the 2.73 gears. You will need a 3 series to use the 3.73 gears. The Eaton posi is the best for street use. It is rebuildable and smooth operating. You will need to get a good installation kit to go with the gears. It will have all of the shims and small parts that you will need to do the swap. The gear that is listed in Summit with no note is for the 3 series differential. If you are going to install the overdrive transmission then the 3.73 will be fine. If you keep the TH350 then you might want to consider the 3.42 gears.