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1st day out after restoration - FMX trans noises
Hi there,
Today, I had my 71 Mach 1 out on the streets after a 4 year restoration. Got me a temporary registration.

The road test was a disappointment. The front end alignment is far from perfect the Mallory ignition module toasted while starting up. I installed my spare distributor.

Mostly annoying was the ugly noise from the freshly redone FMX under acceleration. Some kind of grunt on harder acceleration. It is only present in 1st on launch. 2 and 3 are quiet. Shifting is normal, up and down.

I have readjusted the low/reverse band to make sure it is set correctly. It didn't make it better. Noise is still there.

Fluid is Type F, 11 quarts in the trans.

Does anyone have an idea what that could be?
I do not know what it is but tis article may be helpful in diagnosing the problem. http://www.atraonline.com/gears/1997/199...c97p36.htm
Let us know what you find. Good luck. Chuck
Thanks for the reading stuff.
I just checked the fluid level and found it a 3/16 below "add". Poured in a can of Type F. Will try again tomorrow.

If it still makes the noise, I will drop the pan and check front band adjustment, but afaik the front band is not activated in 1st gear, isn't it?
No advice on the transmission but thoughts of encouragement. It is not unusual for a few issues after a years long effort. What kind of 'grunt' is the transmission making?

73 Convertible - 351C/4V CC heads/4bolt/forged flat tops/comp 270/rhodes/mallory unilite/tri-power/hookers/glasspacks/c6/3.50 limited slip/Gear Vendors/Global West sub frames, strut rods and shelby style traction bars/ Rear sway bar/tilt steering (not original)

Pics of modifications included in:
Difficult to describe. The sound is a non-metallic creak, like it sounds when you go up an old wooden stairway. Or you rub a balloon with your thumb. Only occurs under load and only in 1st gear and in milder form in reverse.

Today, I drove the car 20 miles. After driving some miles, the car felt like "freeing up" like all new overhauled machines when you put them back in operation. The sound was less present after the drive. Maybe the sound is also some kind of friction that has to come into order while in operation. I will have an ear on it.

Here is the finished car after four years of restoration directly after the test drive.

Beautiful car and great color. Good work! Chuck
Wow that was some really good info (link) Chuck. I learned a lot about transmissions. Smile
But Spechti, I would use the methods described in the information and begin your diagnosis using the guage to begin eliminating areas and identifying true problems. Otherwise I think you will be chasing noises for a very long time.

Your Mustang is a beautiful car - I even like that Lincoln Mark IV I spoted in the garage. I had a super nice 71 Thunderbird (same color) I drove ocassionally to High School.

Good luck with your FMX.


1971 Boss 351  
1972 Q code 4 speed convertible 
1971 Mustang Sportsroof  351-2V FMX 
1973 Mach 1 (parts car)
Wow, very impressed with your car. I really like the color combination.

351C 4V cc heads, 10.5 : 1 CR, 290 Herbert cam, Flat top forged pistons, forged connecting rods, Atomic efi,
C6 with Gear Vendor overdrive, 3.89 Tru Trac, Hooker Super Comp with 2 1/2" Pypes Exhaust.        

Some Mod pictures can be seen at:

Wow beautiful car. Looks awesome great work.

He has all the vices I admire and none of the virtues I despise

please contact me concerning the fmx. i might have someone here in vienna who could help you.

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