Okay so i just got a new transmision, new flywheel, new shocks and a bunch of other little things for the car and now what do you know...... i have another problem. I love the car to death but it is the ultimate money pit. But i will never get rid of it so time to fix it again. Now for the problem: when I put the car in reverse and give it a little gas i here this awful grinding noise. If i let the car just roll in reverse its fine. when i go forward though its fine. It does feel a little clunky when it downshifts. The other weird thing i noticed is that when im driving if i hit a pothole or if the car goes over a bump i get the grinding noise again going forward. about 8 months ago both half shafts blew so i put new spicer u joins in and when the transmission was replaced i put new spicer u joints in the drive shaft. when the half shaft blew it tore apart the passenger side slip yoke so I replaced that as well. I made sure to put in the additive when i filled it back up. Anther thing i notice as soon I i started hearing the grinding in reverse and over bumps is that the driver side control arm bump stop was gone. I did replace it though. Oh and the center bushing to the Diff is brand new. Any help would be greatly appreciated. Thanks a lot.

 

could be a broken parking break spring inside one of the rear hubs.

 

Really sounds like the snubber bushing.

 

I replaced the snubber bushing so I know its not that. The parking brake has not worked for a while so that would make sense. But wouldn't I hear the grinding going forward as well? Thanks for the responses

 

sprag in transmission worn or broke. pull pan and see if there is any metal in it. at least its free to look. if no metal top back up and try something else.

 

Thanks. That would really suck seeing how I haven't had the brand new transmision in the car for more than 3 months.

 

hopefully you have warranty but if you dont then not to worry its not a big job to fix , but if its a th350 be sure to replace it with the heavy duty sprag and it wont happen again. its not a B&M or TCI holeshot transmission by any chance is it- good transmissions but unfortunatly dont come with heavy duty spag and will munch up if over 350 hp?...... thats if it is sprag, im just guessing

 

No its a 4l60e from performa built it does have a 2 year warranty.

 

You could check it again.

Since you had the rear apart, I would look there too. A loose pinion would also make this type noise.

 

Thats a good point. Im starting to think that Im gonna have to check out the rear as well. Thanks

 

So i looked under the car and other then the bump stop missing there is nothing wrong. I cant see any rub marks so its something internal. Does anyone have any ideas why i would here the grinding noise when I hit a bump? Thanks

 

So I had my girlfriend move the car up and down the street because she said it didn't sound as bad from out side. After a little bit I noticed the grinding dramatically decreased and sometimes I didn't even hear it while going in reverse. I figured that meant that whatever was grinding has been worn out. I lifted the car and noticed some metal shavings on the drive shaft where it meets the yoke in the rear. I got a mirror so I can see better and I could see that the edge of the yoke has fresh marks on it and the the lip of the differential where it bolts to the frame is grinded down. So my question is what can be making the driveshaft move down far enough to make contact with the the bottom of the differential. Regardless of what some have told me I do not think it's "okay" to just leave it alone just because the grinding has stopped. I don't want to cause serious damage. Thanks for any help.

 

Now we are back to the snubber and bushing.

 

I know but it looks perfect. Im just gonna take it out and make sure it's okay. I really hope this is what it is. Thanks wombvette I'll post what I find.

 

sounds like the bolt from the snubber was grinind on the ujoint or shaft. its that close it could very well be

 

Yes it could be... Did you put the bolt in from top to bottom or bottom to top? If you have it reversed I suppose it could hit.

The bolt should be inserted from the top and the nut, lock washer and flat washer on the bottom.

Another thing it could be but I doubt it is the bushing in the end of the wing.

Willcox

 

I just finished working on her and I found the problem. Well actually you guys found it for me. After taking off the bottom nut from the Differential i sliped the mirror in again and with some light i could really see inside. The bushing was completely out (laying in the carrier) and the round metal pice that holds the upper bushing into place was off as well. It seems to have snapped off the metal insert. Thanks everybody for all your help. Thank you also Wombvette for taking the time to tell me it was the snubber bushing again. If you didn't I probably would still be freaking out thinking I blew the rear. How do you guys think this happened? It looks like the insert was pressed into the washer looking piece. I can't see any cracks and it looks pretty smooth inside. Can I buy this piece alone? The bushing and the bolt look perfect. Thanks again

You can see the bolt with the bushing laying next to it in the mirror