North American Turbocoupe Organization



Difficulty shifting in gear(s)
anasazi4st Offline
Senior Member
#1
Okay, I've run out of ideas, I hope someone here might have some more.

First off: New clutch assembly; new (premium) release/throwout bearing; new pilot bearing; new slave cylinder (carefully bled); new flywheel, all installed about a year ago. Clutch disc was carefully aligned with tool, all steps followed. (Due to various issues such as a leaking T5OD--did not replace o-ring on extension housing [DOH!]--I've had this clutch/transmission out a few times, so it's almost routine now.)

The issue: the warmer the drivetrain gets, the harder it is to shift into the lower gears. Sometimes the car actually seems to "creep" when sitting at stop lights, even with my foot and clutch pedal mashed to the floor. Last week, after a few errands, I COULD NOT get it into reverse. (My solution: turn off car, put in reverse, start car, back up. Not really acceptable.)

The clutch master cylinder was replaced in 2010 (about 16,000 miles ago), so pretty sure it's not that.

In November the car ran flawlessly when my job took me to the White Mountains of AZ (average temps: HI 50s/LOW 30s), and the next week to Yuma (temps: HI 80s/low 60s). I had NO trouble with it then. I first noticed this problem in early January...and in early February I suffered a stress fracture in my left foot that, due to misdiagnosis soon became an actual bone break. Since it was my "clutch" foot that meant no driving the TC until it healed. Last week after medical clearance I drove it for the first time in 4 months, and it was much worse. I have to literally force the shifter into gear, sometimes it won't go and I have to down- or upshift to a different gear to keep going.

Then, suddenly, it'll be okay for a few upshifts...then it's back to difficult.

There are some squeaking sounds of what I would guess is the release/throwout bearing if I disengage the clutch and transmission, but I'm not really understanding how that could be the problem unless the release fork is bad. It's about 15 years old but has no apparent damage or obvious wear, other that what one might expect for normal service.

Does anyone have any ideas? It's starting to get hot here in PHX (119 in a few days, but IT'S A DRY HEAT! Big Grin ). In less than a month, though, the humidity will really kick in when the Monsoons (rainy season) hits. Ugh. Confusedhattered: Without the foot injury I would have likely had this figured out by now, when it was much cooler. I know I'm very probably going to have to pull the transmission off/clutch out for inspection, which might not happen now until October when it starts to cool down to a reasonable climate again; but I was hoping someone might have some suggestions as to what to look for, or maybe it's something else I haven't considered.

Any help would be greatly appreciated. Thanks in advance.
Another proud dues-paying member.

1987 Turbo Coupe w/T5OD, 8.8 axle, grey smoke; most options. Got it in 1991 with 41K miles: 3 turbos, 2 heater cores, 3 T5OD full rebuilds, 6 clutches, 1 head gasket, 2 Teves II ABS units, etc. later....
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Jeff K Offline
Administrator
#2
First thing to do is check the extension of the slave cyl rod. It should extend .53 inches when the clutch pedal is fully depressed.
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 24 psi, forced air IC, water injection, BPV, Ranger cam, subframes, etc., etc.
86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP N2O, ignition, gears, suspension, etc., etc.
11 Crown Vic Interceptor
14 Toyota Camry (wifes car)
95 Taurus GL Vulcan winter beater
67 Honda 450 Super Sport - completely customized
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Pete D Offline
Administrator
#3
Sounds like the clutch is not disengaging enough when warm.

The piece,(bearing retainer, I think) that fits over the trans input shaft, bolts to the front of the trans and it is what the throw out bearing rides on. If it gets gouged up bad enough the TO won't ride smoothly on it. May not be traveling far enough to make the clutch disengage from the flywheel.

Here is trouble shooting guide. http://cart.hanlonmotorsports.com/faq

Good luck with it. The only thing I can offer is don't assume anything is OK. I been bitten too many times by that dog.
Pete Dunham


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anasazi4st Offline
Senior Member
#4
Pete D Wrote:The only thing I can offer is don't assume anything is OK. I been bitten too many times by that dog.
Sounds like great advice.

Jeff K Wrote:First thing to do is check the extension of the slave cyl rod. It should extend .53 inches when the clutch pedal is fully depressed.
That's something I can check on without yanking everything out...which sounds like that's going to have to happen anyway.

Pete D Wrote:The piece,(bearing retainer, I think) that fits over the trans input shaft, bolts to the front of the trans and it is what the throw out bearing rides on. If it gets gouged up bad enough the TO won't ride smoothly on it. May not be traveling far enough to make the clutch disengage from the flywheel.
Why my dear Mr. Watson, I think you might have hit upon something there! That would explain the squeaking, although there's no way to tell until I get it all apart. It had been in pretty good shape, but who knows by now? That's a much better idea than anything I've come up with so far.

Thanks to both Jeff and Pete for some great ideas. I'll let you know.

Another proud dues-paying member.

1987 Turbo Coupe w/T5OD, 8.8 axle, grey smoke; most options. Got it in 1991 with 41K miles: 3 turbos, 2 heater cores, 3 T5OD full rebuilds, 6 clutches, 1 head gasket, 2 Teves II ABS units, etc. later....
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RocketshipChair Offline
Member
#5
Just a quick thought, before you go to tear your trans out.

If you pull the plastic cover that goes over the slave cylinder on the clutch you should be able to see part of the bearing retainer sleeve, throwout bearing, and clutch fork.

As pete said look at the condition of the bearing retainer (its an obsolete part for the 2.3 but there's a company that machines 5.0 bearing retainers to work for the 2.3...I'll post a link if I can find it).

The other thing that may have happened, which is my guess, is the spring on the front of the clutch fork broke off. Unfortunately, the clutch fork is a hard to find piece. But you can repair yours if you sacrifice a 5.0 clutch fork. They use the same throwout bearing and you'll just have to drill out the 2 rivets on both forks and either weld the new spring to the fork (will result in a stiffer clutch feel) or rivet it on.

Let us know what you find.
Andrew
88 Turbo Bird 5 spd no mods
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anasazi4st Offline
Senior Member
#6
RocketshipChair Wrote:If you pull the plastic cover that goes over the slave cylinder on the clutch you should be able to see part of the bearing retainer sleeve, throwout bearing, and clutch fork.
Yes I've looked at that before when it first started making noise before, a few years ago. I couldn't really see much in that little space, but it is an idea worth following up on.

RocketshipChair Wrote:As pete said look at the condition of the bearing retainer (its an obsolete part for the 2.3 but there's a company that machines 5.0 bearing retainers to work for the 2.3...I'll post a link if I can find it).
I actually have a complete T5OD transmission, which was the original one for my car. I replaced it a few years ago with one I rebuilt from an 89 Mustang (I believe). I say complete, but it actually needs several important parts and a complete tune-up set (bearings, synch rings, etc.). My plan is to rebuild it at some point, mostly when I have the several hundred $$ for the kit and parts. But yes, I have a spare bearing retainer, which if I recall was in good shape.

RocketshipChair Wrote:Unfortunately, the clutch fork is a hard to find piece. But you can repair yours if you sacrifice a 5.0 clutch fork. They use the same throwout bearing and you'll just have to drill out the 2 rivets on both forks and either weld the new spring to the fork (will result in a stiffer clutch feel) or rivet it on.
I also have a spare release fork. It was the car's original one that someone DIY'd with a new piece of spring steel riveted on the left side, apparently to fix a broken spring. While it worked before, I'd be hesitant to try and use it again due to the consequences that would result if it fails, i.e. transmission/clutch removal AGAIN. Let's just hope that's not the problem.

RocketshipChair Wrote:Let us know what you find.
If it's weird or different or just out of the ordinary I'll document it pretty well for everyone. I've already got a few projects I photographed for helpful how-to articles, I just have to write it all up.
Another proud dues-paying member.

1987 Turbo Coupe w/T5OD, 8.8 axle, grey smoke; most options. Got it in 1991 with 41K miles: 3 turbos, 2 heater cores, 3 T5OD full rebuilds, 6 clutches, 1 head gasket, 2 Teves II ABS units, etc. later....
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anasazi4st Offline
Senior Member
#7
Here's an update on the Difficulty Shifting Gears issue.

Saturday I raised up the front end and, following RocketshipChair's suggestion, I removed the cover of the clutch slave cylinder to see what was going on in there. As I don't have a lift I wasn't able to look in there directly, but I was able to get some photos of the shift fork and what else you can see of the associated hardware:

[Image: Shift%20fork%20and%20pivot.jpg?dl=0] Springs are holding fork against pivot.

[Image: throwout%20bearing%20fork%20spring.jpg?dl=0] Springs on the shift fork end, holding the throwout bearing. Looks like it's properly in place.

[Image: throwout%20bearing%20in%20background.jpg?dl=0] Throwout bearing as seen on the pressure end of the shift fork.

Since everything looked okay, I hit upon the idea of trying to widen the release gap of the clutch. Right now, one of the problems with the clutch release is that while sitting at a stop light with the clutch disengaged, the transmission is still trying to nudge the car forward. If we accept that pushing in on the clutch pedal presses the release bearing into the disc release springs, disengaging the clutch disc from the transmission, then wouldn't it follow that increasing the release fork's length of travel would cause the clutch to disengage more completely?

To go along with this I added a couple small plastic "cups" (like those found, say, on the fittings of a new power steering pump, to seal it from the atmosphere) to the end of the slave cylinder's actuating arm, on top of the small bushing from the sealing strap. (The cylinder is installed with a strap arrangement in place. The first time the clutch is actuated, typically the straps break free from the cylinder housing, but the bushing remains trapped between the actuating arm and the shift fork.)

[Image: modified%20strap%20end%201.jpg?dl=0] Here's what my invention looked like.

[Image: modified%20part%20installed.jpg?dl=0] And, here it is installed.

Funny thing happened, though--the opposite occurred. I couldn't shift at all. I took off one of the cups, but still couldn't shift. Out of curiosity I took EVERYTHING off, leaving just the rubber end of the actuating arm. Again, no shifting.

I put the OEM strap bushing back on, and I was able to shift gears, although kind of limited (still with difficulty)--just as before.

Again, out of curiosity I got under the dash and folded down the (still original) carpeting so that it was out of the way of the clutch pedal and it would then likely allow it to have more travel, perhaps it would release better. The idea worked in that I could now shift into reverse without difficulty. I decided to take it for a drive, and I didn't get very far before I was again having serious trouble shifting into gear...and again, I could not shift easily in reverse.

Considering that I believe the clutch assembly and related components are all okay (as backed up at least in part by the photos), the only other conclusion I can draw is that the hydraulic system is at fault. Sometimes I can shift easily with no problems, other times it takes serious effort to select a gear. Past experience has shown that to be a master/slave cylinder issue.

The problem with that idea is that while the previous slave cylinder had been on the car since 2014, I replaced it with a new one in January, again hoping that would fix the problem. The clutch MASTER cylinder was installed in May 2010, so my theory is the master cylinder is wearing out/malfunctioning.

When I replaced this part back then I next installed a new(er) ABS master cylinder assembly just afterwards. My thinking was that, since removing the faulty ABS unit made the clutch master cylinder accessible, why not replace it as well? (In other words, there wasn't anything wrong with the one I took off.) I was able to access the clutch master cylinder from just over the fender--I had easy access to it. Now, with the ABS unit in place, I'll have to attempt it from underneath.

Before I do that, though, I've decided to replace the slave cylinder again. It's only $30, and while I'll admit that it's a REMOTE chance the recently installed new part is faulty, it IS much easier--and I think worth taking that chance--before beginning what I think will be a difficult removal and installation of the clutch master cylinder.

What do you think: agree or disagree with my conclusions?
Another proud dues-paying member.

1987 Turbo Coupe w/T5OD, 8.8 axle, grey smoke; most options. Got it in 1991 with 41K miles: 3 turbos, 2 heater cores, 3 T5OD full rebuilds, 6 clutches, 1 head gasket, 2 Teves II ABS units, etc. later....
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Pete D Offline
Administrator
#8
If the slave cylinder yielded an extension of the .53" or more per Jeff above, it should be good. You could carefully peel back the rubber seal on the end of the slave and see how much brake fluid is in it. Moistness or even a couple drops is acceptable. Quantity to drip out is not good. These steps may save you some $$ or point you in a different direction.
Pete Dunham


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anasazi4st Offline
Senior Member
#9
I did not check that measurement when I was down there, I should have.

There is no leakage of clutch (brake) fluid anywhere that I can see in the system; also, the master cylinder reservoir is still full. Is that a general indication of the health of the clutch hydraulic system--leaks/missing fluid? In other words: if there are no leaks in the system does that mean all parts are probably functioning as intended, are fluid leaks one of the first indications that a part has failed?

Also, if the slave cylinder measures to extend out .53" or more, is that also an indication that the master cylinder is doing its job properly?

Thanks for all the help, and thanks in advance for even more of it. Cool

Another proud dues-paying member.

1987 Turbo Coupe w/T5OD, 8.8 axle, grey smoke; most options. Got it in 1991 with 41K miles: 3 turbos, 2 heater cores, 3 T5OD full rebuilds, 6 clutches, 1 head gasket, 2 Teves II ABS units, etc. later....
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Jeff K Offline
Administrator
#10
Yes, if slave extends a minimum of .53 inches, the entire hydraulic system is functioning properly.
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 24 psi, forced air IC, water injection, BPV, Ranger cam, subframes, etc., etc.
86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP N2O, ignition, gears, suspension, etc., etc.
11 Crown Vic Interceptor
14 Toyota Camry (wifes car)
95 Taurus GL Vulcan winter beater
67 Honda 450 Super Sport - completely customized
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