Trouble Changing Down Gears

[Octalicious]

Hello everyone! I was hoping that someone could shed some light on my Gear Change problem?

 

It is difficult to change down gears on my Manual 1.9tdi Octy.

To change down a gear I need to push my Gearstick two gears lower to go down one. Example, from 5th to 4th I need to push to 3rd to select 4th. This applies to any down shift. 

The problem is only present when my car is moving, when static I can change gear perfectly. 

When going up gears; no problems. 

 

I have reset my linkage, changes gear smoothly when stationary. 

My Gearbox oil was changed at the Garage 10 months ago (unknown type).

The Gearbox doesn't crunch when I do change gear. 

My Clutch feels fine. 

Matching engine speed to road speed doesn't help.

The car can Judder when setting off in 1st.

 

 

At the moment I think it could be;

 

Wrong Gearbox oil,

The engine/gearbox mounts,

Synchronisers.

 

If it was the Synchronisers wouldn't some of the gear changes be okay, and would the gearbox crunch? 

 

 

Sorry for the essay, any help would be hugely appreciated!

 

 

[kentphil1]

Can you expand more on the gear changing part of your post, as going 5th to 4th is a pull back action whereas 3rd should be a push action. If you are getting 3rd on a pull back action, something must have gone pretty wrong with the gear lever alignment process. Are we talking 5 or 6 speed manual here?.

[Octalicious]

Can you expand more on the gear changing part of your post, as going 5th to 4th is a pull back action whereas 3rd should be a push action. If you are getting 3rd on a pull back action, something must have gone pretty wrong with the gear lever alignment process. Are we talking 5 or 6 speed manual here?.

Sorry it doesn't make much sense, i'll do my best to elaborate. 

 

It's a 5 speed manual. If I'm in 5th and slowing down I'll pull out of 5th and attempt to pull into 4th. It won't change gear so I need to then push the gear lever towards 3rd to then pull it back into 4th to select 4th gear. I don't select 3rd gear, only push it towards it. I sometimes need to repeatedly push/pull the gear lever to the gear lower than the one I wish to select until it engages. This is the same for any gear I'm changing down to. 

 

I hope this makes more sense, Max.

[dave190]

Sounds like worn dog bone or gear linkages. I would think if it mechanically works stationary what could be causing it? Have you checked the lower tranmission to subframe mount? They can wear on torquey DERF Burners.

I would say change the box oil if you fancied, It's advisable to do that kind of stuff yourself so you know it's done right. But I can't imagine the oil effecting it

[kentphil1]

That makes a lot more sense now, how did you realign the linkage? - more to the point, what instruction source did you use to do it with. These can be a bit temperamental when you do them, and provided the correct procedure is followed, you may need to do it a couple of times to get it correct.

 

Oh and excuse my bad manners, welcome to Briskoda.

[Octalicious]

Sounds like worn dog bone or gear linkages. I would think if it mechanically works stationary what could be causing it? Have you checked the lower tranmission to subframe mount? They can wear on torquey DERF Burners.

I would say change the box oil if you fancied, It's advisable to do that kind of stuff yourself so you know it's done right. But I can't imagine the oil effecting it

Thank you. I will check the mount tomorrow and report back. Changing the Gearbox oil is a good call, the Garage should have used the right oil as they are a locally reputable Garage. I will change it and take that possibility out of the calculation. 

[Octalicious]

That makes a lot more sense now, how did you realign the linkage? - more to the point, what instruction source did you use to do it with. These can be a bit temperamental when you do them, and provided the correct procedure is followed, you may need to do it a couple of times to get it correct.

Thanks for the reply.

 

Free adjusters, lock gearstick, lock selector, lock adjusters. 

 

The gears are changing smoothly when stationary so I'm almost positive the linkage is correct.

[kentphil1]

When you released the linkage ends, were all the legs that grip the cable present?, it is not unknown for one of the legs to break and so slip on the cable during gearchange.

 

The cable only needs to have a couple of mm of slack in the linkage to easily cause the problem you have, and with the engine not running, the syncro hubs are not rotating against the selector forks in the interlock spool. A small amount of misalignment due to either broken fingers or not getting all the slack out of the cables before releasing the ends can feel like the gearbox has had it.

[Octalicious]

When you released the linkage ends, were all the legs that grip the cable present?, it is not unknown for one of the legs to break and so slip on the cable during gearchange.

 

The cable only needs to have a couple of mm of slack in the linkage to easily cause the problem you have, and with the engine not running, the syncro hubs are not rotating against the selector forks in the interlock spool. A small amount of misalignment due to either broken fingers or not getting all the slack out of the cables before releasing the ends can feel like the gearbox has had it.

I believe the fingers are all there, I will double check tomorrow. The gears will change smoothly with the engine running, clutch in and stationary, as soon as I'm moving the gear change down becomes difficult. Could this still be the linkage incorrectly set up? 

 

Do the synchro hubs rotating against the selector forks change the accuracy needed by the gear selector? 

 

Thanks again, Max.

[kentphil1]

Each item on its own should not make a difference, but start with a bit of slack in the cable, add in a bit more movement than normal due to tired engine mounts, then top it off by the synchro hubs holding the spool fractionally out of line due to general wear, and bingo you get baulking. Luckily you can adjust the linkage to edit out about 80% of the movement.

 

Would be worth checking the gearbox mount that the transmission is mounted on is sound as Dave190 suggested, but if the cables are set right, they should allow for fore and aft movement of the engine anyway. Only if the mount is allowing the box to drop quite a way should you use up the cable movement.

 

From memory, when you release the cable end you should get a tripod of 3 fingers, (it may be worth removing the little over centre clip that holds the adjuster end to the gearbox to take it off and have a good look at it) so make sure they are soundly attached and not just resting in there.

 

When I did mine at 120k, I changed both ends for new as one had cracked halfway down under the spring, and also changed the bush at the base of the gearlever, and it turned the box back to nearly new to use. I also gently pushed down on the spool before i locked it with the little L shaped key to make sure it was dead centre before adjusting - these are only details I know but you would be surprised the difference in feel that it makes.

 

If you can, try to get a photo of each end with the spring locked back so we can see the legs - they have a certain look when they're past it, we may be able to help more.  

 

This is what lives inside the box on the end of the spool that the cables operate - http://workshop-manuals.com/skoda/octavia-mk1/power_transmission/manual_gearbox_02j/gearbox_mechanicsoperation_constructiondiff./disassembling_and_assembling_the_gearshift_forks/   

 

As you can see, there are a lot of moving parts that operate every time the linkage moves. When the box oil ages, small amounts of wear start in places like this, so everything does not quite centre the way it did when it was newer.

[KenONeill]

Ref the oil, check the make as well as the right viscosity and VAG standard number; for some reason most VAG boxes don't like Sylkoline gear oils.

 

Other than that, I also wondered about the dogbone and/or linkage alignment.

[Octalicious]

Each item on its own should not make a difference, but start with a bit of slack in the cable, add in a bit more movement than normal due to tired engine mounts, then top it off by the synchro hubs holding the spool fractionally out of line due to general wear, and bingo you get baulking. Luckily you can adjust the linkage to edit out about 80% of the movement.

 

Would be worth checking the gearbox mount that the transmission is mounted on is sound as Dave190 suggested, but if the cables are set right, they should allow for fore and aft movement of the engine anyway. Only if the mount is allowing the box to drop quite a way should you use up the cable movement.

 

From memory, when you release the cable end you should get a tripod of 3 fingers, (it may be worth removing the little over centre clip that holds the adjuster end to the gearbox to take it off and have a good look at it) so make sure they are soundly attached and not just resting in there.

 

When I did mine at 120k, I changed both ends for new as one had cracked halfway down under the spring, and also changed the bush at the base of the gearlever, and it turned the box back to nearly new to use. I also gently pushed down on the spool before i locked it with the little L shaped key to make sure it was dead centre before adjusting - these are only details I know but you would be surprised the difference in feel that it makes.

 

If you can, try to get a photo of each end with the spring locked back so we can see the legs - they have a certain look when they're past it, we may be able to help more.  

 

This is what lives inside the box on the end of the spool that the cables operate - http://workshop-manuals.com/skoda/octavia-mk1/power_transmission/manual_gearbox_02j/gearbox_mechanicsoperation_constructiondiff./disassembling_and_assembling_the_gearshift_forks/   

 

As you can see, there are a lot of moving parts that operate every time the linkage moves. When the box oil ages, small amounts of wear start in places like this, so everything does not quite centre the way it did when it was newer.

Thanks very much for the detailed reply, I have checked the fingers and they have a crack and feel past their best with a potential to slip. I've ordered some more "Bowden Cable Catches". I will take a few pics when I change it and keep you updated. 

 

There is some movement in the bottom mount, as you say it is probably a contributory factor to the poor gear change. If a reset of the linkage with the new adjusters doesn't help I think this should be the next part to change. I've read this could also be the cause of juddering when setting off. 

[Octalicious]

Ref the oil, check the make as well as the right viscosity and VAG standard number; for some reason most VAG boxes don't like Sylkoline gear oils.

 

Other than that, I also wondered about the dogbone and/or linkage alignment.

Thanks for the reply, I've heard the VAG boxes can be fussy. I may change the oil before I do the Cable Catches.