Technical Catching fourth gear

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Technical Catching fourth gear

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Hello panda people.

I'm having my first 'new car' issue, and probably the first of many as I know what new cars are like :D

When I change down from fifth into fourth, I feel the cogs catching as they would if you crunched a gear. It's a split second, with the accompanying noise, then goes into gear fine.

It is fine changing up into fourth. The revs are appropriate for the change down, my foot is firmly on the clutch, but yet this still happens. And not all the time either :confused:

Does anyone with a mechanical mind have an explanation and could maybe either put my mind at rest or refer me to the dealer?

P. S. A coke bottle fits perfectly in the door bins!
 
Hello panda people.

I'm having my first 'new car' issue, and probably the first of many as I know what new cars are like :D

When I change down from fifth into fourth, I feel the cogs catching as they would if you crunched a gear. It's a split second, with the accompanying noise, then goes into gear fine.

It is fine changing up into fourth. The revs are appropriate for the change down, my foot is firmly on the clutch, but yet this still happens. And not all the time either :confused:

Does anyone with a mechanical mind have an explanation and could maybe either put my mind at rest or refer me to the dealer?

P. S. A coke bottle fits perfectly in the door bins!

Never experienced that myself, I have found the gear change to be very smooth....is yours a 4x4? If not mine might have a different box...
 
Never experienced that myself, I have found the gear change to be very smooth....is yours a 4x4? If not mine might have a different box...

Changing gear generally is fine, it's just the fifth to fourth that doesn't sound or feel quite right. Mine is a trekking so has the five speed gearbox mated to the Twinair as opposed to the 4x4's 6 speed.

Is it possible that the gearbox hasn't been assembled properly hence why the cogs are crunching slightly?
 
Hi, the cogs will be permanently engaged as it's a synchromesh gear box - google for details.


The crunching noise will be coming from the synchromesh mechanism as it tries to engage into the cogs, probably because the speed of revolution of the two parts trying to engage is different. The gearbox should allow for this.


My first guess is that as you change from 5th to 4th you are letting the revs drop too much perhaps. As you change from 5th at say 1500 engine rpm, to be in 4th you'd need about 1700 rpm.


Try giving the throttle a little blip to match to the two together (the concept of a perfect gear change) and see if it's any better - not that this is an answer.


There could well be an assembly issue with the gearbox I'd get it to fiat to have a look.


Good luck and let us know.


Just for fun, the reverse gear cog actually engages when you select reverse - it adds another cog into the gear train to change the direction. The reverse cogs are straight cut - i.e. ordinary cogs to you and me. The whine you hear when going backwards fast is the teeth of the cogs slapping together as the forces are transferred from one tooth to the next.


Forward gears are helically cut (it's a curved tooth), these allow the force to be gradually transferred from tooth to tooth and therefore run relatively silent. These gears are engaged at assembly and which gear set is actually used is selected using a mechanism operated by the lever.


Now a really good car would have helically cut reverse gears too, so it would be silent in reverse - not too many of them about anymore.
 
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That's a very detailed answer thank you. I will try what you suggested, if it keeps happening I will go back to dealer and see what's going on. I checked the oil for the first time today, startled by the fact the dipstick is a long grey plastic affair! Very handy having a combined dip stick and filler cap though, I like that idea. Thanks again :D
 
Sounds more like the clutch not disengaging properly - does is still do it if you double declutch? You may just need an adjustment on the clutch. Not very technical but I'm coming from a 127/Classic Panda viewpoint, where I'd be moving a nut up a bolt to cure it! Worth checking before everyone decides the gearbox needs rebuilding (y)
 
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Sounds more like the clutch not disengaging properly - does is still do it if you double declutch? You may just need an adjustment on the clutch. Not very technical but I'm coming from a 127/Classic Panda viewpoint, where I'd be moving a nut up a bolt to cure it! Worth checking before everyone decides the gearbox needs rebuilding (y)

The Twinair's clutch is hydraulic, so I don't think it's likely to be that.

I'd be more inclined to blame the gearshift linkage's adjustment.

Hopefully it'll be easily sorted under warranty, as my Trekking TA's
gearchange is fine :) Now done nearly 8000 miles, still ~55 MPG :D



Chris
 
Sounds more like the clutch not disengaging properly - does is still do it if you double declutch? You may just need an adjustment on the clutch. Not very technical but I'm coming from a 127/Classic Panda viewpoint, where I'd be moving a nut up a bolt to cure it! Worth checking before everyone decides the gearbox needs rebuilding (y)







The Twinair's clutch is hydraulic, so I don't think it's likely to be that.

I'd be more inclined to blame the gearshift linkage's adjustment.

Hopefully it'll be easily sorted under warranty, as my Trekking TA's
gearchange is fine :) Now done nearly 8000 miles, still ~55 MPG :D



Chris







Sounds like syncro to me - warranty job.

Thank you all for the replies, I tried adjusting revs on my commute today, and didn't seem to make any difference. It seems to do it more when changing down to go uphill. As for double declutching, I'm embarrassed to say I had to Google what that is! Didn't want to try on my peak time commutes though as I like to concentrate on the road rather than my clutch work. Looks like I'll be calling the dealer tomorrow :(

Hey Ho, it's a new car and from experience they always have some form of niggle. On a brighter note, 47mpg has happened today :D
 
Alsation1,

Same problem here but interestingly in my case on a 300 mile 4x4 twinair with 6 speed box. Gearbox fine except for - like you - an occasional split second graunch when shifting from 5th to 4th. Only happens about 1 time out of 50 and..... thinking about it and having read your posts and responses thereto above.... more likely to happen if revs have dropped to tick over and/or one is maybe rushing the change a little? It to me almost feels like it does it when the gearlever doesn't seem to have gated across enough to the left during the change and the graunch is happening because the lever is a little midway between 4th and 6th with the graunch happening as the box locates 4th to the left a little after the midpoint on the down(back) throw of the lever. I seem to be able to avoid it by deliberately gating firmly to the left midthrow of the lever as I change. I'm thinking based on the above that maybe the linkage/s need tweaking by Fiat. Fascinating that you have the same problem as me going from 5th to 4th when you have the five speed and I have the six speed! Would love to hear from anyone else with this issue. Please keep me posted as to how you get on when you mention this to Fiat and I'll do likewise.
 
Alsation1, I should add that I actually specifically joined this forum just now to raise the 5th to 4th issue only to find your post detailing the same problem although on the 5 speed rather than 6 speed box which I wasn't expecting!
 
Alsation1, I should add that I actually specifically joined this forum just now to raise the 5th to 4th issue only to find your post detailing the same problem although on the 5 speed rather than 6 speed box which I wasn't expecting!

That is interesting, I haven't actually contacted the dealer yet, as typically for me I get easily distracted and run out of time in the day. So that I don't cause any damage in the mean time I am just changing from 5th to 3rd instead. I WILL phone them today... (he says...)
 
OK, the car is with the dealer as I write this. Miraculously, the car did it to the guy who test drove it, how often does that ever happen?! They're gonna keep it for 'a few days' and see what's happening and also get advice from fiat.

In the meantime, I have a bright yellow 500 as a courtesy car. It'll be sods law that we get loads of snow now :( I have to say, colour aside, I'm not fond of the 500. Steering and ride are not a patch on my panda, I'm not a fan of the overly stylised cabin, visibility is significantly worse than my car and it's a good job I ain't going anywhere as there is no space inside for anything. I'd like to say what engine it is but I don't know. Could be the 1.2 as sounds familiar but it felt pretty gutsy so maybe a 1.4. I miss my 2 cylinder! And why did it have to be yellow!

So far, very very good service from the dealer, let's hope they keep it up.
 
OK, the car is with the dealer as I write this. Miraculously, the car did it to the guy who test drove it, how often does that ever happen?! They're gonna keep it for 'a few days' and see what's happening and also get advice from fiat.

In the meantime, I have a bright yellow 500 as a courtesy car. It'll be sods law that we get loads of snow now :( I have to say, colour aside, I'm not fond of the 500. Steering and ride are not a patch on my panda, I'm not a fan of the overly stylised cabin, visibility is significantly worse than my car and it's a good job I ain't going anywhere as there is no space inside for anything. I'd like to say what engine it is but I don't know. Could be the 1.2 as sounds familiar but it felt pretty gutsy so maybe a 1.4. I miss my 2 cylinder! And why did it have to be yellow!

So far, very very good service from the dealer, let's hope they keep it up.

Post the reg plate and I'll check what engine it is for you.

I enjoyed the 1.2 500 I had for 7 weeks on loan, but couldn't have one as my daily motor due to size :(
 
BF63ZDW is the reg. I think this particular model is one of those 'colour therapy' models with the white wheel trims, aerial and mirrors. And the body and interior are mustard yellow. Really not my cup of tea at all. But at least I got a courtesy car, although I would have preferred a Panda Pop or something more utilitarian :D Even a Doblo or Qubo would have been more up my street. Boxiness all the way!
 
ImageUploadedByFIAT Forum1392318220.986990.jpg
 
Sounds more like the clutch not disengaging properly - does is still do it if you double declutch? You may just need an adjustment on the clutch. Not very technical but I'm coming from a 127/Classic Panda viewpoint, where I'd be moving a nut up a bolt to cure it! Worth checking before everyone decides the gearbox needs rebuilding (y)

If it were the clutch then it would be doing this in all the gears; the OP is specific that it's only 5th>4th, so most likely a synchro fault as others have suggested. It just might cure itself with a bit of running in, but if it's no better after a thousand miles or so I'd be wanting the 'box replaced under warranty.

And for the OP - whatever the dealer may try and tell you, they most definitely don't 'all do this'. Actually the 5 speed unit is generally reliable and very smooth - one of the better bits of the car IMO.
 
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If it were the clutch then it would be doing this in all the gears; the OP is specific that it's only 5th>4th, so most likely a synchro fault as others have suggested. It just might cure itself with a bit of running in, but if it's no better after a thousand miles or so I'd be wanting the 'box replaced under warranty.

And for the OP - whatever the dealer may try and tell you, they most definitely don't 'all do this'. Actually the 5 speed unit is generally reliable and very smooth - one of the better bits of the car IMO.

That's not correct on the older cars - which I made clear was the viewpoint I was coming from. It was only a free and simple check suggestion, which an earlier post said wouldn't apply with a modern clutch system.

If you don't believe me, come and try one of my 127's. You'll crunch it every time going into reverse and often into 2nd. A simple adjustment of the cable cures it (though it's nearly at the end of the travel - still at 35 years old the original clutch is due a replacement!). (y)
 
You'll crunch it every time going into reverse

There's no synchro on reverse and some earlier cars don't have it on 1st either. As you correctly say, on these cars, clunky engagement of 1st/reverse is a sure sign of needing clutch adjustment. Reverse should only ever be selected when the car is stationary and the engine is idling.

Actually the clutch should be checked in every case of clunky gear selection, because any clutch drag will cause excessive wear on the synchro rings.

But in the case of the OP's car, it sounds to me more like a gearbox fault.
 
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