I think my transmission is having problems

[TehMac]

So I drive a 1999 Mustang V6 Manual.

been modded, but the clutch afaik is stock. I'm not sure, but I think it has a short shifter as well.

I notice this occasionally, but it's been happening more lately.

Sometimes when I want to put the car in 1st gear from neutral, the gearbox feels like it locks up--the actual pushing of the gear lever into 1st--sometimes I cannot do it, as hard as I push--I have to slide it into 3rd and 4th a couple of times, and then I find I can push the lever into 1st gear.

The clutch itself seems to have almost no problem.

HOWEVER, I notice this happens when I am backing up in reverse, I don't fully engage reverse because I am afraid of the clutch slipping into reverse completely and then backing up into another car in the parking lot. So I apply a lot of gas while easing the clutch petal in, but never fully engage reverse, then I disengage via clutch petal, and that is when I most often encounter problems with trying to stick the lever into 1st (2nd can be a problem too, but not often)

Another issue I have is when I'm easing in the clutch petal the car shakes. And it's not necessarily uphill. This is when I am easing the petal in from neutral to 1st (gear selected, clutch petal engaging) and the car starts to shake. I give it a lot of gas, but it still shakes.

If I just raise it in and the car starts shaking, sometimes I just lift my foot up completely whereupon I encounter clutch slip as the car lurches into first, sometimes a bit more violently than others.


I just feel that the clutch is a piece of shit, but I had a new clutch put in 2 years ago (or was it 4...big difference I'll have to investigate)

I've driven several other clutch cars including a BMW M Coupe and I have not encountered that problem at all--possibly the clutch is stronger/newer, or the car is more composed.

Anyone have any ideas?

 

[TehMac]

I went on HowStuffWorks and I was reading about transmissions and I came across this:

Another problem associated with clutches is a worn throw-out bearing, sometimes called a clutch release bearing. This bearing applies force to the fingers of the spinning pressure plate to release the clutch. If you hear a rumbling sound when the clutch engages, you might have a problem with the throw-out.

Hrmm, sounds like I had a good idea, it does sound like the throw out bearing is going away.

 

[Vette73]

Does it have a cable or Clutch Master Cyl/Slave Cyl?


If cable try to adjust first.

If fluid then check fluid level and for leaks. See if it is pushing in the fork all the w ay or if one of the 2 main items is weak/bad.


If that checks out 100% then its probable time for a clutch kit.

 

[BlackTigers]

Wait....you don't let the shifter go all the way into reverse? Or did i read that wrong?

 

[TehMac]

Originally posted by: BlackTigers
Wait....you don't let the shifter go all the way into reverse? Or did i read that wrong?

No, lol I fully select reverse on the gear lever stick. So the lever is FULLY snapped into the the Reverse GATE.

HOWEVER, I do not fully engage the clutch pedal as I ease the clutch up, so it's usually, me raising the clutch then LOWERING it again as I disengage the engine, and then if I need to back up so more, I raise the clutch some more until I then disengage clutch with pedal and then shift into first gear

That's when I usually encounter the gear lever's obstinate behavior.

 

[Jeff7181]

I think you need to watch some "how stuff works" videos because it's obvious you don't really understand what's happening when you're shifting gears or depressing the clutch.

I'm curious to know if you let the car roll slightly with the clutch pedal depressed, is it still difficult to get it into 1st gear?

As far as the car shaking, that sounds like a glazed clutch... it was probably overheated at one point which causes a glaze to form on the friction material which doesn't let it slip or engage properly. It's slip, grab, slip grab, slip, grab...

 

[TehMac]

While I don't pretend to know a whole lot, I have been researching how manual gearboxes work for sometime. I am aware of pressure plates, fly wheels, clutch plates, etc.

Obviously I don't know everything or I wouldn't have made a post.


Getting the clutch to actually engage in first gear is no problem. It's actually pushing the gear lever into the first gear gate that is hard. In fact, it's downright impossible sometimes. I have to slide it through 3rd and 4th gates first.

 

[Jeff7181]

Originally posted by: TehMac
While I don't pretend to know a whole lot, I have been researching how manual gearboxes work for sometime. I am aware of pressure plates, fly wheels, clutch plates, etc.

Obviously I don't know everything or I wouldn't have made a post.


Getting the clutch to actually engage in first gear is no problem. It's actually pushing the gear lever into the first gear gate that is hard. In fact, it's downright impossible sometimes. I have to slide it through 3rd and 4th gates first.

I understand... if you let the car roll slightly with the clutch pedal depressed, is it still difficult to get it into 1st gear?

 

[TehMac]

Originally posted by: Jeff7181

I understand... if you let the car roll slightly with the clutch pedal depressed, is it still difficult to get it into 1st gear?

From what I recall, yes, but slightly less difficult.

I don't want to sound like I'm bragging but for the sake of clarifying, I'm not exactly weak, I worked out, etc, it's just the gearbox locks up certain times and then I need to toy with it.

Could just be the "Ford Factor" but maybe not.

 

[Jeff7181]

Originally posted by: TehMac

Originally posted by: Jeff7181

I understand... if you let the car roll slightly with the clutch pedal depressed, is it still difficult to get it into 1st gear?

From what I recall, yes, but slightly less difficult.

I don't want to sound like I'm bragging but for the sake of clarifying, I'm not exactly weak, I worked out, etc, it's just the gearbox locks up certain times and then I need to toy with it.

Could just be the "Ford Factor" but maybe not.

I won't say it's normal, but it's not uncommon for a gearbox to resist going into gear when you dry shift (ie. shift while stationary).

My best guess is that the fork is slightly bent from someone doing just that too often and forcing it into gear. Combine that with normal wear and you have a transmission that's hard to get into gear even while in motion.

 

[TehMac]

Originally posted by: Jeff7181
My best guess is that the fork is slightly bent from someone doing just that too often and forcing it into gear. Combine that with normal wear and you have a transmission that's hard to get into gear even while in motion.

What would you recommend?


I think I need a new throw - out bearing. That's the issue related to the car shaking when I ease the clutch into first (this happens occasionally, but everything I'm doing is perfectly normal--I have not encountered this in any other manual car I have driven).

 

[boomerang]

You say you think it has a short throw shifter installed. The first thing I would check is the linkage. Make sure what needs to be tight is tight and what needs to be loose is loose.

The shifter itself could need some attention also. There are a number of wear surfaces that could stand to be looked at. It's a good time to dissasemble it, check for wear, lubricate and just give it a going over. As was said you may have a bent fork in the trans itself, or it could even be a synchro problem. Start the engine with the clutch in and then, with the engine running (in neutral), try engaging the clutch briefly, disengaging it and then putting into first. See if you get better results that way. That will get the input shaft spinning and should assist you in putting it into gear.

The shaking you refer to sounds as though the clutch needs some attention. You've been told that already.

I don't want to come off as an ass (anymore than I am) but, the nomenclature needs work. In, out, up, down, easing in, etc. - no. The clutch is either disengaged or engaged. If you're in the process of actually moving the pedal, use the terms engaging or disengaging.

If the pedal is at the floor it's disengaged. If it's up all the way it's engaged. If you're pushing the pedal down you're disengaging the clutch, If you're letting the pedal up you're engaging it.

Really, I'm not trying to be a dick, I just am having a hard time following what you're trying to say.

In addition to the suggestions you've already gotten, you could have a broken motor mount or transmission mount. That could skew everything out of alignment enough to be causing some of the problems you're having.

 

[Jeff7181]

Originally posted by: TehMac

Originally posted by: Jeff7181
My best guess is that the fork is slightly bent from someone doing just that too often and forcing it into gear. Combine that with normal wear and you have a transmission that's hard to get into gear even while in motion.

What would you recommend?


I think I need a new throw - out bearing. That's the issue related to the car shaking when I ease the clutch into first (this happens occasionally, but everything I'm doing is perfectly normal--I have not encountered this in any other manual car I have driven).

In my experience you'll almost always hear the throw-out bearing grinding which changes when engaging/disengaging the clutch before you feel any difference.

Bucking almost has to be the clutch simply because nothing else can cause that, short of tap dancing on the accelerator, brake or clutch pedal.

Best thing you can do at this point is probably get a new clutch. It may require replacing the flywheel and pressure plate depending on how bad the heat damage actually is. If only the friction disc was damaged then you can probably get away with resurfacing... when in doubt, replace it all.

While you're doing that (or having that done) it wouldn't be a bad idea to replace the throw-out bearing while it's torn apart since that is a wear item.

 

[TehMac]

I dunno, none of this sounds right. Maybe it's just the fact that my transmission is a piece of shit and my driving habits exacerbate me noticing these issues?

 

[Zenmervolt]

Originally posted by: Jeff7181

Originally posted by: TehMac

Originally posted by: Jeff7181

I understand... if you let the car roll slightly with the clutch pedal depressed, is it still difficult to get it into 1st gear?

From what I recall, yes, but slightly less difficult.

I don't want to sound like I'm bragging but for the sake of clarifying, I'm not exactly weak, I worked out, etc, it's just the gearbox locks up certain times and then I need to toy with it.

Could just be the "Ford Factor" but maybe not.

I won't say it's normal, but it's not uncommon for a gearbox to resist going into gear when you dry shift (ie. shift while stationary).

My best guess is that the fork is slightly bent from someone doing just that too often and forcing it into gear. Combine that with normal wear and you have a transmission that's hard to get into gear even while in motion.

You're right that it's not uncommon, but it's probably not a shift fork if the issue is intermittent.

Think about how gears mesh for a minute. Notice how the teeth need to hit at the right spot for the gears to come together; if the teeth met tip-to-tip, the gears would bind and not mesh. That is what happens sometimes when a gear cannot be selected and you need to select another gear to "move" the teeth just enough to get things to engage.

ZV

 

[Jeff7181]

Originally posted by: Zenmervolt

Originally posted by: Jeff7181

Originally posted by: TehMac

Originally posted by: Jeff7181

I understand... if you let the car roll slightly with the clutch pedal depressed, is it still difficult to get it into 1st gear?

From what I recall, yes, but slightly less difficult.

I don't want to sound like I'm bragging but for the sake of clarifying, I'm not exactly weak, I worked out, etc, it's just the gearbox locks up certain times and then I need to toy with it.

Could just be the "Ford Factor" but maybe not.

I won't say it's normal, but it's not uncommon for a gearbox to resist going into gear when you dry shift (ie. shift while stationary).

My best guess is that the fork is slightly bent from someone doing just that too often and forcing it into gear. Combine that with normal wear and you have a transmission that's hard to get into gear even while in motion.

You're right that it's not uncommon, but it's probably not a shift fork if the issue is intermittent.

Think about how gears mesh for a minute. Notice how the teeth need to hit at the right spot for the gears to come together; if the teeth met tip-to-tip, the gears would bind and not mesh. That is what happens sometimes when a gear cannot be selected and you need to select another gear to "move" the teeth just enough to get things to engage.

ZV

You're right, and forcing it into gear will bend the shift forks and/or linkage. If you exert enough force, it will slip into gear as I've never seen a synchronizer that didn't have beveled teeth on the blocker rings.

 

[TehMac]

Originally posted by: Zenmervolt

You're right that it's not uncommon, but it's probably not a shift fork if the issue is intermittent.

Think about how gears mesh for a minute. Notice how the teeth need to hit at the right spot for the gears to come together; if the teeth met tip-to-tip, the gears would bind and not mesh. That is what happens sometimes when a gear cannot be selected and you need to select another gear to "move" the teeth just enough to get things to engage.

ZV

Yea, this makes sense, I like this Jeff and ZV, great minds put together, fantastic!

So, would this mean I should get a new shift fork?

 

[Jeff7181]

Originally posted by: TehMac

Originally posted by: Zenmervolt

You're right that it's not uncommon, but it's probably not a shift fork if the issue is intermittent.

Think about how gears mesh for a minute. Notice how the teeth need to hit at the right spot for the gears to come together; if the teeth met tip-to-tip, the gears would bind and not mesh. That is what happens sometimes when a gear cannot be selected and you need to select another gear to "move" the teeth just enough to get things to engage.

ZV

Yea, this makes sense, I like this Jeff and ZV, great minds put together, fantastic!

So, would this mean I should get a new shift fork?

Don't open your wallet before checking it out, but yeah. If a fork is bent it gets replaced. From the sound of it, you need a new clutch too.

 

[TehMac]

So, I was experiencing the shaking problems again today. And I have noticed I still get a bit of shaking as I'm raising the clutch pedal, but the shaking really gets bad in the afternoon--a combination of heat from the sun and engine fatigue, which means whatever issues the clutch elements are having, it seems like its exacerbated by the heat.

 

[SJP0tato]

Just to chip my $0.02 in: I agree with Zimm & Jeff it sounds like your clutch is on the way out. When my clutch broke around one of the springs it exhibited symptoms similar to what you're describing. When the metal around a 2nd spring broke I could no longer get it into/out of gear without extreme effort.

If it has been more than 20-30k miles, you may also want to change your transmission oil. I have noticed a slight lessening in effort when I change the transmission fluid after I've gone 25k+ miles.

 

[TehMac]

hrmm...I changed my engine oil, it's quite possible my tranny needs an oil job.

 

[TehMac]

I did a diagnostic test with a friend, he's a mechanic of sorts (works on rockets and restores cars for fun) and he thinks the clutch itself is dying. So I'll probably install a new clutch in there for Christmas and spend 300 extra bucks for a racing clutch so I don't need to worry about the damn thing for the rest of its existence.