Why does my car shake when letting off the clutch in first gear

[Slow_v8]

My 2004 manual mustang shakes and the shift knob too when letting off the clutch in first gear. Does it mean I have a bad clutch? When I bought it was good never shook when my dad drove it but I did learn manual in this car stalled many times so is it a bad clutch or sum else?

 

[RAU03MACH]

Could be
Will it go in every gear while driving

 

[Slow_v8]

Yeah and it doesn’t pop out or nun it’s just first gear and reverse. It won’t shake if I give it gas to like 1500 rpm but if I just use clutch it shakes

 

[cobrajeff96]

Sometimes it's not a clutch issue or even anything in the drivetrain but rather a suspension issue. You could have 'wheel hop' which is an oscillation of suspension bushings during power application, mostly at low speed when there's sudden change of inertia. It could also be caused by bad pinion angle, but that's a little more rare. Bad shocks might even play a part for if they can't dampen the wheel motion then all that energy will transfer into the chassis.

But the diagnosis depends on more information. Clutch age/miles, OEM/non-OEM, age/miles of the cable/throwout bearing, fork, etc., age/miles of the suspension components. Et cetera.

 

[GTamas]

I have similar problem in my 94, the clutch and TB are fresh, but the flywheel and cable were never replaced. I'm planning to first change out the cable. If it doesn't solve it, I will replace the flywheel.

Just curious, how is your clutch pedal feel? Mine is pretty stiff, hard to push in.
Although your car has a hydraulic clutch if I'm not mistaken.

 

[96blak54]

Ive seen a clutch that had broke up. Parts of the disk chipped off. The friend asked to borrow the lift to swap out his clutch because he could feel it slip and suspected the vibration was from the clutch too. We changed it, the clutch was broke in many pieces. We turned his flywheel, installed a new clutch and no more vibration or slip. Hope this helps

 

[Mustang5L5]

Trans mount cured a lot of the vibration issues I had with my car. WOuld shake when letting out the clutch and when i hit 3K rpm on the highway at any speed.

New trans mount and smooth and silk to 80+MPH.

 

[cobrajeff96]

If a new flywheel isn't installed at the same time a new clutch is, or is at least put on a lathe to smooth out the FW if it is a serviceable FW, then that could also be a cause of driveline vibration. Both surfaces have to be machine-flat, or as about as perfectly flat as possible.

 

[RAU03MACH]

Could be an RPM problem idling to low
Reverse and 1st steep gear need a little help from throttle

 

[CobraRGuy]

That sounds like clutch chatter. As cobrajeff96 mentioned, both the flywheel and pressure plate surfaces need to be like new when the clutch is assembled. Resurfacing the flywheel when a new disc and pressure plate are installed will provide the best results.
There can be a more mysterious cause as well. I put in a new FR clutch (King Cobra if my memory is correct) and discovered that the spline count on the disc was not correct for my tyranny. I bought a different brand disc with the correct splines and the clutch chattered horribly even though all the surfaces were good when installed. I was told that not having matched components can cause that.
I eventually bought a complete Superior Friction clutch (now part of Modern Driveline). I now have the most awesome clutch on the planet. Not only do I have no chatter, but this clutch has progressive engagement, a light pedal and prodigious grip. I can break the rear tires loose at 90mph if I try (and I have a Torsen T2-R diff).
When the clutch was first installed I took the car for a drive and noticed that the clutch started slipping when I put my foot into it. I called the mfgr and was told that is not only normal, but I should put more power into it to make it slip more. They said that the parts were being "mated" to each other and that I'd get less and less slip as things broke in. That's exactly what happened. Now it's just perfect. Good luck.
CobraRGuy

 

[tvsn95]

I agree that you should inspect the rear suspension bushings, and take a look at the tran mount also. would not surprise me if you found one of the lower control arm bushings split.
Cobraguy thats the craziest clutch story I have ever heard,,,I learn something new every day.
I have had an Ass of clutch problems and now run a Mcloud RXT all metal setup, works good and soft pedal , It will break everything in the driveline,,, I know well
The RST would last 20 min then warp the floater, then shifting was TOUGH.

 

[Slice]

Trans mount cured a lot of the vibration issues I had with my car. WOuld shake when letting out the clutch and when i hit 3K rpm on the highway at any speed.

New trans mount and smooth and silk to 80+MPH.

Yeah have a knowledgeable mechanic check the motor and transmission mounts. Those sort of things perish over time.

 

[cobrajeff96]

Usually you can just see the cracks in the rubber if they're real bad. But really, you don't need a guy to check it for you. You just take a pry bar or crow bar and try to lift the tail of the transmission away from the crossmember mount. Try short but fast movements at first with not a lot of elbow grease and see if it moves (or even separates entirely!). You'll know it if you see it. Because if the trans can move even just a little bit with not a lot of force from you, just imagine what it would look like when your car is bouncing up and down the road at speed (or when sending a lot of force to the tires at a standstill trying to move a 3500 lb Moosestang)

 

[Joeminnesota]

Could be trans mount or could also be a motor mount. Trans mount is an easy fix and not expensive.

 

[Slow_v8]

Sometimes it's not a clutch issue or even anything in the drivetrain but rather a suspension issue. You could have 'wheel hop' which is an oscillation of suspension bushings during power application, mostly at low speed when there's sudden change of inertia. It could also be caused by bad pinion angle, but that's a little more rare. Bad shocks might even play a part for if they can't dampen the wheel motion then all that energy will transfer into the chassis.

But the diagnosis depends on more information. Clutch age/miles, OEM/non-OEM, age/miles of the cable/throwout bearing, fork, etc., age/miles of the suspension components. Et cetera.

Never mind guys this build is a no go. Some bitch did a u turn when I was already hella close and had right of way.

 

[tvsn95]

Dam shame,, I know I sweat everytime I go out in mine. But I am still doing the PowerTour this year.

 

[RAU03MACH]

Never mind guys this build is a no go. Some bitch did a u turn when I was already hella close and had right of way.View attachment 34896

Looks fixable

 

[RAU03MACH]

Sorry to see that
Majority looks cosmetic
I think it can be repaired
You'll have to take your time

 

[cobrajeff96]

Fuggin animals out there

 

[RAU03MACH]

mindless idiots
people do not care what they do they have a dont give a shit attitude