Whenever I am in low gear (lets say second) and I let go of the gas to kind of coast, leaving it in gear, I get a clunking sound from somewhere in the drivetrain....Its kinda hard to explain, but sounds like the driveshaft moving back and forth under the car (I know thats not it, but thats just an example of what it sounds lke)...I'm pretty sure this is not normal since I do not remember this on my 00GT (I have an 03GT now) but I'm not positive...Anyone have this, or know what this is? Is this normal? Or will this develop into a bigger problem? Any help would be appreciated....thanks...

 

There is a lot of backlash on my 04 GT... if I am slowing down and leaving it in gear, just before I pass the point where the car would start slowing down, I just push the clutch in, little embarrasing to essentially bump a wall because of the backlash. It makes a bit of a bump sound when I don't get the clutch in in time and the play in the gears comes to an end, but it is not major.

 

yeah thats the kind of thing mine does...Is this a problem? Or will this get worse....It almost feels like something could be adjusted or tightened down but I'm not sure...

 

The cause is excessive driveline lash likely caused by the rear gearset setup having too much play Even though you hear it through the floor under the trans/driveshaft area its originating from the rear and ending at the point of the driveline that has some"flex" in it. -Which is the u-joints. My car did that quite a bit, as it should after almost 150,000 miles. The rear was just redone again (after I swapped in 373's then took em out 2 days later) and after reinstalling my original 273's and all new bearings and seals and setting the ring and pinion up correctly the car barely if ever does that at all anymore. But to answer your question that appears to be what causes that on manual trans cars its much more noticble than on auto cars though.

 

so can this be adjusted when I get new gears/kit?

 

I noticed that my 04 GT does the same thing when I'm in second. If I'm coasting slowly in second and "goose" the gas a little bit, the car kinda lurches after I let go of the gas and I get that knocking back and forth sound. Mine sound like it's coming from the driveshaft too. I didn't think much of it until I read your post.

 

MY 02 with 20K miles does the exact same thing. I've asked this before and it seems most have it and its just the nature of the beast. It would be nice to have a fix, but i dont know if there is an easy one.

 

I think I going to try getting the rear end compenents replaced then when I get new gears....Hopefully that will fix it...I only have like 50,000 miles so I didn't think t was something that was failing....But all in all, it probably is just the way the car is....Unless someone knows of any other reason....