Guys i once raced like a fool and broke the clutch plate from one area , then the car wouldnt get into gear as the plate was stuck.

Got the car towed to a workshop ,they replaced the clutch and put everything back together.

But now there is a noise which isnt noticable on low rpms but the moment i put my foot down , specially in 2nd some kind of noise starts coming from under the car , like the exhaust is in contact with the drive shaft.

 

They failed to properly align the frame that the transmission is mounted to, its called the "powerplant frame" or "PPF". Search on this site for more info about it. I had the same problem, as have other people. You can't just casually bolt everything back up when re-installing the transmission. It needs to be aligned (according to the instructions in the mazda service manual) so that the engine, tranny, differential, and chassis are all aligned.

But you need to bring it back to them and they should be able to fix it in 15 minutes. They didn't follow the proper instructions. You could probably do it yourself with the right tools, but honestly they screwed it up so they should fix it for you.

 

Those a**holes also snapped off two bolts from the gearbox mounting then they had to heat them up , then get em out.

I will give it back to them as you pointed out the problem and i know your are right.

Thanks alot

 

I had a similar sound when I replaced my exhaust and we just bent the PPF 1/4" or so so it wouldn't chatter anymore. There really isn't much aligning to be done if I remember correctly though.

 

The car felt totally **** to drive after the change , i mean everytime i put my foot down it was like the whole underbody was loose really annoying , like having damn church bell on your head.

 

Can you explain that better? It is possible that something else wasn't done.

 

The time i took it home from the workshop , it happened.

It got less noisy after a couple of runs. But there was a huge difference before i took it to the workshop by which i mean it got alot worse when i was taking it home , they checked everything else the next day except from the transmission frame which another user stated.

There was alot more vibration , this happened over a year ago so thats all i remember. Its been unsolved since then.

will get it aligned and lets hope for the best.

 

You bent the Power Plant Frame?!
How did you bend it anyway...

The PPF does need to be properly aligned, though you can usually tell where it was by the circles created by the large nuts.

 

My mechanic had it up on his lift...put a large block of wood on the piece of the PPF that was being vibrated against by the exhaust and hit it with a 20 lb sledge. It wasn't the best idea I am sure...but it doesn't rattle any more. It wasn't like I needed to bend the whole thing...just the one small 1/2" section that was rubbing on the exhaust. Didn't touch the bolts...stayed away from the drive shaft.

 

But that only made noise on higher revs?

 

its probably not bent, just wasnt aligned as it should be as part of the normal isntallation procedure. seriously, search for it and see how people describe it. Do you have something like a grinding or scraping noise when you let off the gas in 2nd gear (with the car still in gear). If so, that's the problem. I cant imagine how you'd bend it...

 

shawns - yes...it only occurred at higher revs because engine vibrations are greater at higher revs.