The (seemingly common) 2002-2007 Corolla "notchy" gearbox...

[Jonesy038]

Hi guys

I've had a bit of a read around on the forum on some old threads concerning this and have noted various suggestions/theories, including simply "the boxes are rubbish".

But I bought my 2006 VVTI Corolla 1.4 in 2014 with a mere 38k on it. It has now done about 110k. For about the last 10k miles or so, it has become progressively more difficult to make certain gear changes. 3rd gear can be particularly hard to engage and you can find yourself floating along the road with the clutch down and having to shove it 5 or 6 times to get it to engage. Even selecting first gear can be tricky. It wasn't like this for the first few tens of thousands of miles but it is definitely getting worse. 

What's the current thinking on this problem? The main dealer wants 84 quid an hour to diagnose it and, frankly, given the age of the car, I'm not sure how many hours I want to pay them rummage around for, only to then tell me it need an uneconomical amount of work doing. It's a shame, because the car is still in great nick and I really love it.

I don't think it's the clutch - if I slow down to 15-20 mph, stick it in 4th and put my foot down, it doesn't slip. But then again I know naff all about cars compared to most people on here. I just don't want to bin what is otherwise a great car unless I have to. Could the clutch pedal adjustment described in the Haynes manual make any difference?

On the other hand, I don't like driving the kids around in it and risking floating out onto a busy roundabout frantically trying to ram it into gear....

Would really appreciate any thoughts on this - thank you. 

[TonyHSD]

Hi, 

there are 3 major points you will need to double check either as diy work or garage (mechanic). 
1. Gearbox oil - check for traces of metal with magnet and do swirls if oil create some sort of colourful tails in the swirling. Change the oil with new exact spec. 
2. Double check clutch if operates as it should, the friction plate might be ok so no slipping can occur but if the diaphragm springs are cocked then it might not work properly. , this will be accompanied by heavy feel in the clutch pedal. 
3. Clutch gear cables and shifter and the hydraulics if it’s hydraulic clutch, I have no idea of the car in question and I can’t be more specific. 
Hopefully someone who has experience with exact coed car can be of more help. 

Good luck 
 

[Jonesy038]

Thank you for those thoughts. Much appreciated.

i meant to add that changing down is generally worse than changing up - for example I can usually go from 2nd to 3rd with little trouble. But from 4th down into 3rd, that’s more problematic. 

[flash22]

2nd to 1st, 4th to 3rd, - stretched cable - adjust or replace the cable

 

in 1st and 3rd you are pulling the cable, what can stretch the cable with the mileage it also wears the eyelets on the gearbox end

edit. iirc adjustment is at the shifter end

[Gerg]

We have a 2001 1.4 vvti Corolla, the model before yours but mechanically very similar indeed.  It's done 142,000 miles

We have had the car from new, it is still on the original clutch, which has been a little heavy for some years.

The symptoms you describe do have some vague familiarity to something we have had, but not to anything like the degree you are suffering.

When the transmission gets sticky and a little obstructive, I remove the trim around the gear stick to get a proper access to that area, and slowly drip oil onto the ends of the gear shift cables.  The oil goes into the cable, perhaps aided by capillary action.  But I move the gearshift around to help in this as well. 

I also locate the other ends of the cables at the gearbox end, pull back the rubber protective bellows, and slowly drip some oil onto those, too.  The job doesn't get rushed - the oil doesn't go into the cable quickly.  I use engine oil, but I've experimented with 3-in-1 oil, and maybe other oils I think.

Finally, I put some grease (this is usually Castrol LM general purpose chassis grease because it's to hand, but the type isn't really critical) on the large ball arrangement at the bottom of the gear stick.  Spray-on 'white' grease is probably your best bet.

Over time, the gear change then gets better until you don't notice it at all.  I've probably done this three times or so in total over the years, and it's feeling like it could do with doing again.  (I only drive the car very occasionally, its now driven by my son.)

I can make no promises as to if this'll improve your problem.  But I hate a rubbishy gearchange action, and like oiling things (sad, but there you go...), so this seemed the logical thing to do to help our one!

I should mention that I use an old inkjet printer cartridge refill container (bellows-style), to which I've added a WD40-type delivery tube, as the oiling can.  This helps get the oil in just where I want it without drowning the whole area in lubricant.  But this d-i-y oiler arrangement isn't essential, you just need some time and some clean rags.

I don't know why the cables should need oiling, as far as I can make out they have a plastic lining which ought to make them maintenance-free.

It's also worth carefully checking that the driver's floor mat isn't riding up under the clutch pedal.  If it does it'll likely ruin the gear change feel.  It might be best to remove the mat completely just to be sure this isn't happening.