rebel1222

My son's car has all of a sudden started making a loud clunking sound and slipping during ecceleration. I tightend up the tranny mount so that is eliminated. I feel certain it is the rearend. I inspected the underneath and everything looks good. The drive shaft isn't loose and the rear wheels turn freely. It only does it during take off.

I haven't taken the cover off yet, but It's as if there are teeth missing and it is hitting them during take off. Once the car gets going it stops.

Should I try and get a whole new rear end or just replace the gears in this one?

Any suggestions would be much appreciated.

Zepher

iTrader: (1)

broken teeth usually makes a horrible clunking sound that doesn't go away.

pop the cover and inspect the gears.

slipping during acceleration is probaly the transmission as there is nothing in the rear that can cause slippage.

did you look at the torque arm mount on the side of the tranny as well?

rebel1222

The sound is for sure coming from the back of the car. Perhaps slipping was the wrong term. It is a horrible clunking sound with the rear end kind of bouncing up and down until the car gets going. Then it doesn't do it. It seems espesially bad in turns.

By torgue arm mount are you talking about the torsion arm that goes from the tail of the tranny and bolts to the rear end housing? That is good and tight.

Zepher

iTrader: (1)

could be the carrier bearings have gone bad, or the carrier itself is broken.
pop the rear cover off and see if the carrier moves forwards and backwards when you turn the wheels. might have to hold one wheel still while turning the other one.

rebel1222

I took the rear cover off and found that the drivers side "side gear" wash shredded. The teeth have been mashed away, leaving a metal paste all over the magnet attached to the cover.

Having no experience whatsoever in rebuilding rear ends, (i have swapped out one on a chevy truck before), where can I get one of these side gears? Do I have to buy the whole rebuild kit, or can I just get the one gear? I looked on the autozone website and do not see this gear, only the ring and pinion.

Here's a diagram from another post. it is the drivers side "side gear".
https://www.thirdgen.org/forums/tran...make-posi.html

big gear head

Is it 26 or 28 spline? The S10 trucks have the same differentials, so if you find a S10 rear end that you can get parts from you can swap them. Be sure to take your old gears with you to be sure that they are the same size. I've seen different size gears in these. Be sure that you get the correct splines too. The 7.5 10 bolt had 26 spline axles up to '90 and then they got 28 spline axles. This is the same for all 7.5 rear ends in trucks, Camaros and anything else that used this rear end. If you don't have any luck finding a set then let me know. I can get you a new set. Don't just replace the one gear, replace the set.

rebel1222

Thanks very much for the info BGH. I called the chevy dealer, gave them the vin #. They gave me a price and a part number. I then went online the RyeValley Gear and ordered the spider gear kit for 117.50 including shipping, (dealer wanted $323 for it). It is a 10 bolt, 28 spline, 7.5. Supposed to fit 82 and up camaros and a host of other gm vehicles. The car it's going on is a 2000.

Now, I just need to find some detailed directions on how to remove the old and install the new without screwing it up. :-)

big gear head

Remove the bolt that holds the cross shaft in. Remove the cross shaft. Push the axles in and remove the c clips from the ends of the axles, then pull the axles out about 3 inches. If you have disc brakes you will have to remove the calipers first. Turn one axle gear and the pinion gears will fall out. Pull the axle gears out. Be sure that you get the thrust washers out when you remove the gears. There is a thrust washer behind all 4 gears. Put the new thrust wahers on the axle gears and oil them. Put the gears in. Line up the pinion gears EXACTLY opposite of each other with the thrust washers on them and turn an axle gear so that the pinion gears line up with the hole in the cacse for the cross shaft. Push the axles back in and put the c clips back on. Put the cross shaft back in and put in the retaining bolt. Trque the bolt to 20 foot pounds.

rebel1222

Thank you very much for the info. I'll print it out and follow it when doing the job. I should have the parts in by Friday. If so, I'll replace the spider gear Saturday or Sunday. I'll let you know how it turns out. Thanks again.

Duffster

IF it's a 2000 Camaro/Firebird, you might have traction control and have difficulty pulling the c-clips behind the dogbone. IF you have traction control, there are a pair of sensors that use 10mm bolt (1 on each dust shield) that need removed prior to pushing in the axles to disengage the c-clips.

Good luck.

elano

iTrader: (2)

You should be able to do it while it's still in the car. When you are putting it back together, put the side gears & washers in first, then put one spider gear in and spin a side gear until it gets 180 degrees from there yo put it in, then put the other spider gear in and then spin the side gears until the holes line up with the cross-shaft holes in the carrier, then slide the axles back in but be careful not to let the gears fall out, put in c clips, then slide shaft in and tighten the nut. Good luck.

rebel1222

Thank you all very much for the tips and instructions. I'll do my best this weekend to get it going again. I'll let you know how it works out.

rebel1222

What is the trick to get the spider gears to fit in after the side gears are placed back in? I can't get the spiders in with the side gears in theres not enough room. I know there is a way, i just haven't found it.

big gear head

Did you compare the new gears to the old ones? All 7.5 differential gears are not the same. Some are thicker than others. It's possible that you have the wrong gears. If you have the right gears then you can use feeler gauges or other thin tools to help guide the gears into place. If you put a thin layer of grease on the thrust washers that will help hold them on the gears.

rebel1222

Right after I typed the last post I went down and figured it out. It's all back together and runs and shifts very smooth. Thanks to all of you who helped me out with your knowledge and experience.

big gear head