Car Mechanics... halp! (Gearbox woes)

[MenaceMartin]

Hi peeps. Any mechanics in the house? It would be awesome if someone were able to give me a second opinion about this

I'll cut to the chase. Since last winter, when my car has been running for around 15 minutes, the gear change will steadily start to stiffen up, almost to the point of having to use two hands to shift (not recommended i'm sure). Now, at that point it was only occasional, and actually stopped altogether eventually, however, when we went away on vacation for 2 weeks in July and the car was sitting un-used, the exact problem is back.

I went to our local garage last week, awesome guys, but they are just as stumped as i am. After spending £200 on new cables, and having all the linkages checked, greased and lubed, the problem still persists. I went back, and after some phone calls, to gearbox specialists, they can only recommend changing out the gearbox fluid, and rechecking the links.

If that doesn't sort it, i'm looking at around £500 for a gearbox overhaul. Way too much for me right now, and i gotta say, i'm a bit sceptical the fluid is to blame. Can it really cause this problem?

It's totally temperature dependant, will do it even with engine off/clutch depressed, and running the car for ten minutes, and then turning it off whilst it is still loose and free, returning to the car 30 minutes later (once the heat has had time to linger), it's stiffened up.

Car has done just uner 40000 miles... surely the box isn't goosed already? Any tips/options/'your screwed' comments are more than welcome, and much appreciated. It's a royal pain in the arse and makes the car almost undriveable.

 

[sonar1]

Sounds as if the pilot bearing is binding up. It is a bearing that holds the pilot shaft of the transmission in the center of the flywheel. If it gets bound up from sitting (or from heat after warmup) the input shaft of a manual transmission will turn at engine speed even with the clutch disengaged, and your synchros will not allow the trans to be put into gear.

Try turning off the engine, placing the car in gear (this may take a few tries or changing from other gears to get a spot in the gears which will mesh), then restarting with the clutch disengaged. If the starter is bogged down trying to start the car, then either the throwout bearing that disegages the clutch is bad, or the pilot bearing is seizing intermittantly. A bad throwout bearing does not usually change with conditions or be intermittant. I'm betting the pilot bearing (in the center of the flywheel) is the culprit.

Once "broken loose" the pilot bearing will be ok until it again comes to rest. Shifting becomes difficult, and getting into first from stopped is almost impossible against the syncro which is trying to match input shaft with final drive shaft within the trans. Throwout bearings can sometimes seem this way briefly before all control is quickly lost and it becomes obvious the clutch will just not disengage. When it's the pilot bearing, the clutch will "feel" normal at the pedal (they feel different when a throwout bearing goes), but it feels as-if the transmission is not disengaging from the engine (like the clutch is not working).

The pilot bearing is not large nor expensive. However it will require pulling the transmission to get at it. May as well do a clutch and throwout bearing while you're in there.

Once the pilot has seized you can press in the clutch and brakes at the same time while coming to a stop and it will break it free again, temporarily. Does this seem to be happening?

I'm suspicious of that pilot bearing because I've seen this happen before with vehicles that sit for a period and then are put back into service.

 

[Daniel]

Try changing the fluid... Be sure that the correct spec is used... If that doesn't work the only thing beyond that is to tear it down.

And yeah, could be a pilot bearing or the clutch... Does it feel funny?... Any chatter when it gets hot?

 

[MenaceMartin]

Sounds as if the pilot bearing is binding up. It is a bearing that holds the pilot shaft of the transmission in the center of the flywheel. If it gets bound up from sitting (or from heat after warmup) the input shaft of a manual transmission will turn at engine speed even with the clutch disengaged, and your synchros will not allow the trans to be put into gear.

Try turning off the engine, placing the car in gear, then restarting with the clutch disengaged. If the starter is bogged down trying to start the car, then either the throwout bearing that disegages the clutch is bad, or the pilot bearing is seizing intermittantly. A bad throwout bearing does not usually change with conditions or be intermittant. I'm betting the pilot bearing (in the center of the flywheel) is the culprit.

Once "broken loose" the pilot bearing will be ok until it again comes to rest. Shifting becomes difficult, and getting into first from stopped is almost impossible against the syncro which is trying to match input shaft with final drive shaft within the trans. Throwout bearings can sometimes seem this way briefly before all control is quickly lost and it becomes obvious the clutch will just not disengage.

The pilot bearing is not large nor expensive. However it will require pulling the transmission to get at it. May as well do a clutch and throwout bearing while you're in there.

Once the pilot has seized you can press in the clutch and brakes at the same time while coming to a stop and it will break it free again, temporarily. Does this seem to be happening?

I never thought of that! That does seem entirely plausible. I don't even think the garage guys have thought of checking that.

It's quite strange though, it's not like the 'engaging' of gears is difficult. There's no grinding or any abnormal noise, that i can hear anyway For instance, say the shifter is in 1st... and i go to pull it down into 2nd, it is stiff all the way. Same with 3rd to 4th, 5th to Reverse and vice versa. However, it is always free when in neutral and moved left to right (wiggled), it's just the forward/back motion is stiff through it's entire movement when things are warmed up That was why we thought the primary cable was the culprit.

I'll mention this to him though, as we want to eliminate all possibilities, and it does seem like it could in fact be the issue.

Thanks for the reply!!! I really appreciate it

Try changing the fluid... Be sure that the correct spec is used... If that doesn't work the only thing beyond that is to tear it down.

And yeah, could be a pilot bearing or the clutch... Does it feel funny?... Any chatter when it gets hot?

Fluid change tomorrow, and the mechanic is even nice enough to do it into closing time due to my work schedule. He wants to get it sussed out as much as i do, kudos to him! There's no audible chatter or misc noises that i can hear, and performance-wise it's absolutely fine.

If the fluid change doesn't work, then i guess i have no option but to get it overhauled asap before more problems occur. Won't be cheap, but hey, it's my pride and joy... a small price to pay in my books

Thanks again for the replies guys. It's very much appreciated!

 

[sonar1]

... There's no grinding or any abnormal noise, that i can hear anyway For instance, say the shifter is in 1st... and i go to pull it down into 2nd, it is stiff all the way. Same with 3rd to 4th, 5th to Reverse and vice versa. However, it is always free when in neutral and moved left to right (wiggled), it's just the forward/back motion is stiff through it's entire movement when things are warmed up...

Hmmmm. Well there shouldn't be any noise if the sychros are doing their job, but reverse has no synchro. If it were the pilot bearing or throwout bearing it would grind and absolutely NOT go into reverse while running, were the pilot bushing galled.

Is that "stiffness" there even when turned off and cold?

Could be the shifting dogs or forks are not properly sliding (low on gear lube in the box?).

If they checked the gearbox fluid level, then yes 40K is very early for it to be acting up that way (with the proper lube at the proper level).

 

[MenaceMartin]

Hmmmm. Well there shouldn't be any noise if the sychros are doing their job, but reverse has no synchro. If it were the pilot bearing or throwout bearing it would grind and absolutely NOT go into reverse while running, were the pilot bushing galled.

Is that "stiffness" there even when turned off and cold?

Could be the shifting dogs or forks are not properly sliding (low on gear lube in the box?).

If they checked the gearbox fluid level, then yes 40K is very early for it to be acting up that way (with the proper lube at the proper level).

When they were replacing the cables, i don't think they checked the fluid level, as i think we were all pretty convinced the cables were the issue. Perhaps it could be low fluid rather than bad fluid right enough?

When the car is cold, shifting is really easy... i can even shift with only my little finger, and that is if the engine is on or off. After things have heated up and running for around 15 minutes, it becomes gradually stiffer. Once it has stiffened up, it will be stiff even when the engine is off or on, and there's nothing i can do in the car to leviate the problem, other than stopping driving altogether as my arm get's increasingly tyred

PS. One thing i don't think i mentioned before is that if i'm driving on the motorway (5th gear at 70mph) the problem get's worse a lot quicker. I put this down do thing's getting hotter quicker because of the increased speed?

 

[redcoats1976]

my moneys on low fluid...the big question is where did it go after only 40,000 miles?noticed any spots on your driveway where you park?

 

[sonar1]

...if i'm driving on the motorway (5th gear at 70mph) the problem get's worse a lot quicker. I put this down do thing's getting hotter quicker because of the increased speed?

5th is likely an overdrive, which involves a gear set. 4th may be direct through and run cooler.

Now it's starting to sound to me like there's not enough lube in the gearbox.

Which begs the question, where did it go? Most manual gearboxes are sealed up. The only place the lube could get out is likely the shaft seal at either end. This would leave drips or puddles under the car (unless it's burning off on a hot piece of exhaust pipe, which you'd smell). Again, 40K miles is early for that type of seal to have a problem unless there's damage from something.

In any event have the gearbox lube level checked immediately! There will be a square end threaded lug about halfway up the side of the box you can remove (with a wrench) and stick your finger in. If lubed at the correct level a drop of oil should present itself when you pull the that threaded plug on the side, as usually the lube level is supposed to be right at the level of the plug..

 

[TOMMYTHUNDERS]

 

[Mule Train]

Don't buy any more Chevettes?

The gear box does not have fluid it has oil. Automatics have fluid.

 

[GNR4EVR]

Look at the fluid thats removed for "silvery" appearance- thats usually telltale of not so good things to come.

 

[MenaceMartin]

Ok, this photo was taken after i took the cover off around a month ago when i started trying to diagnose the problem...

As you can see, at the bottom where the actuator goes into the casing, there is oil residue. I told the mechanic from the start about this and that i was unsure if it had anything to do with it... nothing more had been mentioned and he didn't seem to see it as an immediate problem.

I got the car back today after getting even more lubing up of the linkage and an oil replacement (for free). He told me the oil that came out was black, and quite smelly. So, i took the car to my Fiancee's and back again tonight (around 40 miles) and whilst it is far better so far (he says it may take a few days to clear up), the stiffness is still there a bit, but no where near as bad as it was.

Just to check things after i parked up at home, i looked under, and on the bottom of the cover, there is more oil. Maybe not enough to drip, but enough to generously coat my fingers. I smelt it and it looked pretty fresh, so it's hard to tell if it's overspill or some continued leaking (i can't get under the car to get the cover off at the moment so it's hard to tell).

To me, it looks like theres some sort of broken/worn seal where that actuator enters the box? Surely that can at least contribute to the problem, as it's that mechanism which moves inward and outward when i change gears? I'm beginning to think to myself that it's best just to get the whole thing out and overhauled and hopefully be done with it.

Thanks again for all the help chaps, it's a huge help! I'm almost at my wits end with this!

 

[Laaz]

Don't know what kind of car it is, but does it have a clutch slave / master cylinder ?

 

[MenaceMartin]

Don't know what kind of car it is, but does it have a clutch slave / master cylinder ?

Cheers for the reply It's a Ford Fiesta (2007). Indeed it does, it's a hydraulic clutch, however we've pretty much dismissed the clutch as being the issue pretty early on. A dragging clutch can cause similar problems, but this problem happens even when the engine is off and appears to be totally temperature dependant

 

[Laaz]

Like your brake master cylinder, the clutch master cylinder controls fluid pressure. I would start there.

 

[Daniel]

Cheers for the reply It's a Ford Fiesta (2007). Indeed it does, it's a hydraulic clutch, however we've pretty much dismissed the clutch as being the issue pretty early on. A dragging clutch can cause similar problems, but this problem happens even when the engine is off and appears to be totally temperature dependant

I'm not terribly familiar with Ford gearboxes but I've been a BMW tech / mechanic for 30 years... And that is pretty odd.

I'm interested in knowing what your guy finds.

Like your brake master cylinder, the clutch master cylinder controls fluid pressure. I would start there.

Not really... All it does is transmit motion from the pedal to operate the clutch.

 

[crawlingkingsnake]

Does your vehicle have a slave cylinder on it? That could be what is causing the leak. Which in turn would indicate signs of a bad pilot bearing/throw-out bearing. (Not ruling out a bad pilot bearing) If you have a faulty/leaking slave cylinder there isn't enough pressure exerted on the clutch fork, which the pilot bearing is attached too. When this happens the pilot bearing doesn't engage the pressure plate as it is intended.
A comparison of a faulty slave cylinder. Would be like driving an older vehicle that has a bell crank ( say like an older dodge car or truck). If you were to press the clutch pedal half way to the floor, and tryed shifting. It would be pretty hard to shift, if at all possible. That's due to the linkage only allowing the clutch fork to travel so far, and not allowing the throw-out bearing engage the pressure plate properly.

I have dropped alot of transmissions thinking it was the pressure plate, clutch disc, and throw-out bearing needing to be replaced. Then come to find out it was the slave cylinder faulty. This happens a lot on Toyota's and Nissan's that use the slave cylinders.

Your application could have a internal slave cylinder that could be leaking out, and running down onto that seal area. I guess an internal/external slave cylinder could leak down into that area. Again not sure what the vehicle is, just trying to help with the knowledge I have.

If the problem is internal, my guess would be the beginning of a worn synchro. Which could be the result of improper fluid or fluid levels. Fluid type is detrimental to any transmission, whether it be a automatic or manual.

I hope you can get this sorted, the cheapest way possible bud. What is the make and model of the vehicle? And what engine is in it? I have manuals to just about anything. I might be able to help with some research.
Good Luck Bro..

 

[crawlingkingsnake]

Well Shit. I guess it took my old ass way to long to reply..

 

[rjshare]

how can you tell when gearbox oil smells funny? it fvckin reeks at the best of times!!!

 

[Daniel]

Well Shit. I guess it took my old ass way to long to reply..

I've got that problem as well... I'm not sure if it's my slow typing of if I just space out a lot.

how can you tell when gearbox oil smells funny? it fvckin reeks at the best of times!!!

You got that right... Most gear lubricants smell like halitosis to me.