Curious Shifting Issue


nota4re

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Feb 15, 2006
4,294
Just reading this thread this evening. I too am hoping it is just the clutch not releasing as opposed to any transaxle problem. It was a relief to see the correct fluid was used! It seems that the lead theory is that the clutch is not releasing completely. When this is occurring, many times it is very difficult to engage reverse or first gear when completely stationary. Is this happening?

For the record, we have been working on Ford GT's since 2006 and have done countless transaxle removals, clutch repairs, etc and never once have we had to use the intermediate clutch bleed nipple. Just sayin'.

Another test for a "sticky clutch" is to get the car on a perfectly flat surface and with the car in first gear, start letting the clutch out until the car starts to creep forward, then slowly press the clutch back in to see if you are getting complete disengagement.
 
  • Like
Reactions: Nafod

GT@50

GT Owner
Mark II Lifetime
Dec 14, 2019
950
Issaquah
Just reading this thread this evening. I too am hoping it is just the clutch not releasing as opposed to any transaxle problem. It was a relief to see the correct fluid was used! It seems that the lead theory is that the clutch is not releasing completely. When this is occurring, many times it is very difficult to engage reverse or first gear when completely stationary. Is this happening?

For the record, we have been working on Ford GT's since 2006 and have done countless transaxle removals, clutch repairs, etc and never once have we had to use the intermediate clutch bleed nipple. Just sayin'.

Another test for a "sticky clutch" is to get the car on a perfectly flat surface and with the car in first gear, start letting the clutch out until the car starts to creep forward, then slowly press the clutch back in to see if you are getting complete disengagement.
Not sure if it's more, "praying to god" vs theory.
I've seen the hose off the reservoir feeding the master leak cause problems on a couple cars(couple out of thousands I've done, not GT)
Aside from leaking, T/O bearing would have to be destroyed if it were the cause. You'd know it.
Bad pilot bearing will cause "drag" that could make it stiff to shift. You might hear a funny little chirp when shifting.
Clutch discs binding on splines will cause "drag". You might be able to drive this out.
I've never changed a clutch master on a GT but on a Ford Ranger, Fiero, and a couple other vehicles it is a major task to bleed them out completely. On the Ranger I'll get the master level and start bleeding it(not easy), then install and finish. On the Fiero I'd jack up the front only to start the process, lower, and jack up the rear only to finish. Most cars that are "difficult" to get bled out I'll force fluid from the slave to the master, works well.
 
  • Like
Reactions: GTMD

Special K

GT Owner
Mark IV Lifetime
Aug 23, 2016
1,781
Franklinton, LA
With the engine off and clutch pedal depressed, does the transmission shift through the gears easier than when it is running? If so, that could point to partial engagement of the clutch.
 
  • Like
Reactions: GTMD

PL510*Jeff

Well-known member
Mark IV Lifetime
Le Mans 2010 Supporter
Nov 3, 2005
4,901
Renton, Washington
I had a simular issue "way back when". Ended up that the shifter cable jacketing had melted, causing the shifting problems. Keep in mind the shifter cables run through the valley of the engine. It gets way hot down in there.

We went through all the steps mentioned. Finally a call was made to "the right man" at Ford who immediately diagnosed the problem. So we took off the top of the motor to expose the shift cables. Sure enough the jacketing had melted and allowed the spiral cable tube to bind.

A pair of new cables were sent to the shop. Had a hand written note - do not adjust these cables as they are perfect.

Put the new cables in - right out of the box. Found some heat padding in the truck shop and wrapped the cables with it. And, after a trip to my race shop, we covered everything with heat reflective flue tape. Re-did the mounting stand-offs due to the increased size of the wrapped cables.

And never had any shifting issues since. From what I remember, we were told this is a fairly unusual problem.
 
  • Like
Reactions: GTMD

GTMD

GT Owner
Mark II Lifetime
Jan 4, 2011
957
NorCal
Not sure if it's more, "praying to god" vs theory.
I've seen the hose off the reservoir feeding the master leak cause problems on a couple cars(couple out of thousands I've done, not GT)
Aside from leaking, T/O bearing would have to be destroyed if it were the cause. You'd know it.
Bad pilot bearing will cause "drag" that could make it stiff to shift. You might hear a funny little chirp when shifting.
Clutch discs binding on splines will cause "drag". You might be able to drive this out.
I've never changed a clutch master on a GT but on a Ford Ranger, Fiero, and a couple other vehicles it is a major task to bleed them out completely. On the Ranger I'll get the master level and start bleeding it(not easy), then install and finish. On the Fiero I'd jack up the front only to start the process, lower, and jack up the rear only to finish. Most cars that are "difficult" to get bled out I'll force fluid from the slave to the master, works well.

Thanks for the suggestion. Yeah, I kind of doubt a throwout bearing given that there are no other symptoms and with such low miles but the leaking master cylinder hose is an interesting idea too. I'll definitely inspect!
 

GTMD

GT Owner
Mark II Lifetime
Jan 4, 2011
957
NorCal
With the engine off and clutch pedal depressed, does the transmission shift through the gears easier than when it is running? If so, that could point to partial engagement of the clutch.

Hmmm, that's a great question and interesting idea. I want to say yes, seems to be absent when not running, but I'll have to check today. Thanks for the suggestion!
 
  • Like
Reactions: Special K

GTMD

GT Owner
Mark II Lifetime
Jan 4, 2011
957
NorCal
I had a simular issue "way back when". Ended up that the shifter cable jacketing had melted, causing the shifting problems. Keep in mind the shifter cables run through the valley of the engine. It gets way hot down in there.

We went through all the steps mentioned. Finally a call was made to "the right man" at Ford who immediately diagnosed the problem. So we took off the top of the motor to expose the shift cables. Sure enough the jacketing had melted and allowed the spiral cable tube to bind.

A pair of new cables were sent to the shop. Had a hand written note - do not adjust these cables as they are perfect.

Put the new cables in - right out of the box. Found some heat padding in the truck shop and wrapped the cables with it. And, after a trip to my race shop, we covered everything with heat reflective flue tape. Re-did the mounting stand-offs due to the increased size of the wrapped cables.

And never had any shifting issues since. From what I remember, we were told this is a fairly unusual problem.

Wow! I've heard of this happening once before too. Crazy! I doubt that's it on this car only because it has been slowly getting worse the last 2-3 drives without any high temperature cycles and I think it's better when the engine is off but I need to check that still. Also, seems to shift much easier through the higher gears. But I'll definitely keep it in mind. I also thought of a cable adjustment issue too but I'm not going to touch them without any experience, especially when I have other things to check first! :) Thanks again Jeff!
 

nota4re

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Feb 15, 2006
4,294
You can test the shifter cables by disconnecting them at the transaxle. Before that, however, I think you can get a good sense of the health of the cables. Sitting in the car, clutch in and engine off, the shifter should move fore/aft (like a 1-2 shift) and side to side (toward passenger side and back) in the neutral gate. Both of these should seem equally smooth. (One cable is responsible for fore/aft and the other is side to side.) Again, these movements should feel equally smooth.

With that test done, I would go ahead and start the engine and with clutch-in, go through the gears. Shifting should feel the same as engine off. Place the shifter in neutral and let the clutch out and then back in and repeat the gear selections with clutch-in. You can do this several times and see if the clutch dis-engage works the same every time.
 
  • Like
Reactions: analogdesigner