Rokkaholik

I've been noticing lately that my Mustang has a weird cut chunk or clunk noise after shifting either up or down. It doesn't stay continuous and it doesn't sound like grinding in any way. Just a slight clunk what I would normally associate with a bad u-joint or rear-end gears getting sloppy. It's like something is just barely loose enough to be annoying. It also has a little bit of a whine almost as if there was a supercharger under the hood which there is not.

After doing a lot of searching and reading, it appears that the two-piece drive shaft in these cars is quite a turd. At first I was hoping I could get away with just a U-joint or something but it looks like now there might be more issues arising.

Options: fix current drive shaft or whatever piece needs it so I don't have to fight pinion angles and all that jazz

or

dig through pocket lint and scrounge up money for the Ford Performance one-piece I saw.

Pros or cons to either? Looking for specific stories/experience 05-09 mustangs

or

it's normal and just turn the radio up and ignore it? 🤣🤣🤣

ill try to get a video/recording of the offending noise

Bert

yeah my first guess is you are hearing/feeling the slop in the driveshaft, it could be coming from any of the joints or more likely it is the sum of all the joints ... each time the driveshaft goes slack it makes the thunk and then when power is re-applied it thunks again in the other direction as the slack is taken out

If you replace the factory two-piece driveshaft with an aftermarket one-piece, yes that does eliminate the joint in the middle and any slop in that joint ... but it will make the pinion angle more critical .... I am told that if the car is not lowered then the factory setting should be OK; but if the car is lowered then you may need an adjustable upper control arm to adjust the pinion angle

first step might be to get under there and try turning the driveshaft by hand and see if you can figure out where the slop is

Rokkaholik

Mine isnt lowered at all....

I'm fairly mechanically inclined, but not so much with manual transmissions as I have never owned one. I'm still somewhat a novice trying to figure out the quirks of how this car sounds and the things that it does. It very well could be that this is just the normal noise that comes out of this specific Mustangs two-piece drive shaft and manual transmission for all I know. I just am a very proactive person and I prefer to fix things or deal with them on my time versus at the most inconvenient time.

m05fastbackGT

For what it's worth, I also have the stock 2-piece driveshaft and despite my car having a lowered suspension, I haven't noticed anything in the driveshaft which describes as slop in neither feeling or hearing...

Are you absolutely certain that what your describing is definitely from the driveshaft or could it possibly be coming from a sway bar end link or perhaps a loose transmission or engine mount

Bert

yeah it could be other things .... but my experience with my 2010 is like this:

• when I shift, if I don't clutch-in soon enough, and there is some forward pressure on the driveline from the engine braking as I let off the gass, the slop in the drivetrain is taken out in the "forward" direction and there can be a small clunk, but the bigger clunk comes later
• after the shift when I re-engage the clutch, all that "forward" slop is taken out in the other direction, and that's when you hear/feel the clunk
• if you are careful not to allow "forward" pressure on the drivetrain before the shift, then the clunk after the shift is much less (because there is less slop being taken out)

it's like trying to do precision work on an old worn milling machine .... as long as you keep going in the same direction, there is no issue ... but as soon as you turn the crank the other way, you feel the slop and you have to "recalibrate" for that or all your measurements off the gages on the machine will be wrong, due to the slop

05stangkc

Not Sure If I Had Posted This Before in Any of Your Threads But if Not See Post 4. This Might Work For You!

https://themustangsource.com/forums/...p-link-550939/

KC