:wave:
I discovered yesterday a "unique" probem that one can encounter with a semiautomatic gearbox; or at least the Fiat semiautomatic gearbox using a "manual" style dry clutchplate.

They can when on the limit get "bogged down"; :bang:leaving you with a slipping clutch and impossible to get wheelspin or enough power to the wheels to pull you through and out. You quite literally in my case have a "beached" car.


Background:-
I do a lot of running and sea swimming (triathlon training); and most days this means I have to drive along a beach. I mean drive actually on a proper beach (no road).

The beach is a combination of sand; gravel, shingle; and it varies considerably in softness and slope. The winter storms here changed the whole dynamics of it.

Yesterday I discovered a unique problem with the semi auto gearbox that you can encounter..
The car in question was a 2007 Fiat Panda Elengaza 1242cc semi automatic gearbox.
15,500 miles and in perfect working order.

Gearbox is working perfectly. Good job Fiat.....only issues with it has been sometimes when it gets "confused" when pulling off. If you accelerate; and then have to suddenly back off it can stall. This has happensabout six times a year. That is not a gearbox fault on ours, I believe; it is just how they are. Just sloppy design for that situation.

For many years I have been driving along this beach. All my historic Citroens (soft suspension/big tyres) have never got stuck.

My Fiat Uno (manual) was touch and go with its smaller wheels. But when it did bog down on this terrain the *only* way to "continue" was to let the wheels spin and as it dug down it just found traction on the subsurface layer and "jumped/hopped" forward. No amount of clutch slip would allow it to drive through. On this terrain with this car you had to let it wheel spin and hop to get any headway.

A normal automatic is often much easier to drive offroad (at least uphill or on the "flat" as the "fluid" coupling allows less wheelspin pulling off. -Downhill can be a different matter though with runaway/lack of engine braking)

Yesterday it was sunny.
I arrived on the beach as normal to find a variety of 4x4's parked. Beach party.The only way along the beach was on the softest ridgiest bit, between the parked 4x4's; people; dogs; kids; berms and the waves themselves.

Generally I think Fiat have seemed to have done a good job on the gearbox. But I had the usual wheelspin/hopping; and of course trying to balance it without a clutch is a little different to a manual. In some ways easier and some harder. But usually you can drive them in the same way as a manual car off road.

However I was eventually left with semi buried wheels (maybe up to hub deep at the greatest depth).....eventually with *full* power and accelerator fully down with *NO* wheelspin. Stuck :bang:
A bogged down; beached panda.

The car was just holding the engine revs there (slipping) on the clutch- engine revving away. Not enough drive to the wheels to pull me through, or curiously wheelspin. Of course (clutch) smoke started to come---very quickly actually.

Ideally Fiat need to "rejig" the sensors to *allow* wheelspin under extreme full throttle. It did not matter how I applied the power. Snapping it on or building it up. Same result;not enough drive to the wheels to move or to wheelspin.

I cant remember at this precise point whether I was trying to go forwards or backwards to navigate my way around the berms/cars. I had to shuffle. But fortunately (and only just) by going into a forward gear/or reverse.....did I just manage to break the "hold" on the cars wheels by the beach material; and promote a wheelspin to claw out.

I admit this was extreme terrain; and of all the off roading I have done in my life (quite a lot); it was some of the most demanding in terms of purchase and drag on the car.

Incidentally all the other cars on the beach were four wheel drives. Two Mercedes (2WD's) did try and venture onto the easy part of the beach. They got stuck. Totally. They had to get towed out by a landrover.

I watched this unfold swimming from the water.
It is only really BMW's and Mercedes that I have seen getting totally stuck on the beach...rear wheel drives as always.


Two main points came out of this.

Under more harsh (but not that extreme) offroad conditions you may have to drive the semiautomatic Fiats differently to either a manual or an automatic car "offroading"--when they are on the limit.

Secondly I was suprised on the Fiat at how quickly the clutch started to smoke. I have driven many other Citroens, some Ford's and Alfasauds with full power and fully loaded clutch slip before; either off road or towing boats up steep boat ramps; and have never had clutch smoke in such a short period of time.

It makes me wonder whether Fiats have weaker clutches than historic Citroens and other cars?

The beach is just within traction limits. There is no point in my trying to alter or adapt the car for this beach. However if I was doing more or a transcontinental trip again in a semiautomatic; then I would look into how to overide the sensors; to "allow" me to wheelspin under more extreme conditions.

So if Fiat read this......you need to alter the parameters/tuning of your microchips or sensors. They fall short in this area.

If only I could also fit a manual clutch pedal also onto the semi-auto box. Best of both worlds:slayer:

All in all a good gearbox. But they need to be remapped in at least two areas.; for off road driving extremes; and the stall thing at junctions.

Ironically the problems are the opposite of each other. on one the clutch slips; and on the other it does not (hence the stall)!

Come on Fiat--I know you can solve this and do better!

although being honest when fiat designed and built the car they probably didn't think they needed to take into account someone driving it on a soft wet sandy surface with little to know traction.

they probably assumed if anyone needed to do this then a panda 4x4 might have been a better purchase

this type of gearbox is always going to have its limitations as its software and sensors, however doing something outside the capabilities of the car then complaining its can't handle it, is doing your poor little panda an injustice

Seems like a lot of words here to complain that a 2wheel drive car got stuck in wet sand!

Whatever turns you on, I suppose.

Sweetsixteen.

AndyRKett said:

although being honest when fiat designed and built the car they probably didn't think they needed to take into account someone driving it on a soft wet sandy surface with little to know traction.

they probably assumed if anyone needed to do this then a panda 4x4 might have been a better purchase

this type of gearbox is always going to have its limitations as its software and sensors, however doing something outside the capabilities of the car then complaining its can't handle it, is doing your poor little panda an injustice

Click to expand...

All my other 2 wheel front wheel drive cars; both manual and automatic have been fine.
But I do admit the beach conditions on this day were some of the worst.

It is a definite design shortcoming; in these particular set of circumstances; on this Fiat semiautomatic gearbox. Which otherwise and on balance I have to say I think is a brilliant gearbox.

It is not just about going off road. The same in theory could apply while towing a heavy trailer up a steep slope.

Because all four wheels were "held" by sand/shingle wrapped around them; the gearbox would not allow enough power to be put to the wheels to move the car at all. Neither could it spin the wheels.

That is a design shortcoming.

As for the comment about four wheel drives; people very rarely need them . I have only had two. One to drive across the top of Iceland; and the other to drive across the top of Lesotho. My other transcontinental trips (Europe to Asia; New Zealand etc)have all been 2wd. I crossed parts of the Sahara in a two wheel drive Renault 5.

I feel strongly they need to remap the clutch system at this "low end".

AndyRKett said:

although being honest when fiat designed and built the car they probably didn't think they needed to take into account someone driving it on a soft wet sandy surface with little to know traction.

they probably assumed if anyone needed to do this then a panda 4x4 might have been a better purchase

this type of gearbox is always going to have its limitations as its software and sensors, however doing something outside the capabilities of the car then complaining its can't handle it, is doing your poor little panda an injustice

Click to expand...

If one thinks about it, in this situtation with this gearbox on its current standard settings) four wheel drive would have made no difference in getting the car out.. It actually could have made "getting out" worse.

Remember wheel slippage and traction was not the problem. There was infact too much traction and grip on the front wheels; and the gearbox could not overcome the resistance required to turn the wheels and get the car moving. It could not put enough power in, to use the grip and turn the wheels at all.

If this car was four wheel drive there would have been even more resistence for the engine/clutch to over come to get the car moving; both from the rear wheels and the extra transmission resistence to the rear wheels. So even more clutch slippage, at the expense of wheel slippage/traction.

Thats the other way around of course to the 'normal' situation . If a 2WD does get stuck normally it is due to insufficient driving traction on the wheels causing them to spin. That is when having 4WD can help. But in this particular situation the car could not put enough power to even just the front driving wheels to turn them at all.

It was only just myself in the car. So the car was as light in weight as it could have been.

I hope that makes sense.

So you can get the best of both worlds (between auto and manual) with this 'semi' gearbox. But it can leave you in 'nomansland'.

I may raise it with Fiat sometime to see if they have anything to say about it. I doubt they will though. They may not even be aware this problem exists.

I feel your pain

Here is a post I made a little while ago (in another forum) in response to towing with an automatic.

I would also add that with my Stilo Abarth Selespeed semi auto box reversing a 1000kg caravan/trailer up hill was a real clutch burner basically going nowhere fast. I gave up as soon a I smelt the clutch.

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There are these days basically two types of automatic gearboxes - excluding CVT:

1) Traditional auto with fluid torque converter and multiple "clutch" wet plates

2) Traditional manual gearbox with either one (or two) dry clutch plates where the gear change and clutch(es) are electro hydraulically operated either under computer controlled or driver operated gear change "paddle" or "sequential" lever shift change where the computer does the clutch control.

I'm led to believe that towing with 1) is a dream and something I've not done.

However I have towed with 2) and for normal and performance driving it is a dream BUT WITH A BIG BUT!!!!!!

2), not having a torgue converter, uses traditional "clutch slip" when starting (an minimal or no slip when driving). It is the clutch slip that can be a real problem in traffics queues and crawls. Even worse in reverse.

To explain in more detail, in a traditional manual box and clutch you get slip the clutch in 1st, get the masses moving and then take your feet off all the pedals and the car will chug along at engine idle speed. Even when starting off you can on a level surface have no need to pick engine revs off idle to get rolling.

With 2) at a stop and engine idling the computer disengages the clutch completely. You then have to lift the revs for the clutch to start to engage. Depending on the towed load, incline etc. the computer controls the clutch slip. Sometimes it will start to engage at say 1000rpm and slip to say 1500rpm. Others slip will continue to 2000 rpm or more.

When stuck in a traffic jam every start/stop the clutch slips. However if the queue is slow eg. slower than a 1st gear 1500rpm crawl then the clutch is constantly slipped by the computer. Worse with load/caravan and ever far worse on inclines. There is no way you can achieve a good old 1st gear rolling feet off drive.

Also most of these 2) gearboxes increase the slip, and thus smooth control when reversing (due to the different reverse gear ratio).

I use to dread being caught in queues for fear of stuffing the clutch prematurely. So when the queue moved I would wait, let the gap grow still I could be in a position to get to 1500rpm where the clutch slip stops. Only problem with this is that some inpatient person would see the gap and switch lanes causing you to slow down and enter the clutch slip zone again.

Now I'm possibly more mechanically minded than most, having worked on and serviced all our cars for 42 years, and thus potentially over sensitive to anything that increases wear and could give me additional work to do etc.

To sum up, a traditional fluid torque convert does not wear like conventional clutch plates when slipped.

Hi S130

There is a third way too (as there often is) in addition to what you mention. But yes your two options are mainly the ones of today.


VARIATION 1
The Citroen C Matic system used essential a manual gearbox also with a torque convertor. The driver phyically selects a gear using a gearstick. But the car (and Citroen hydraulics) do the clutch work for you. The car stays in the gear that you have selected; until you change it yourself just like in a normal manual car.

However there is no clutch pedal.....the car does that for you with sensors/switches on the gear stick etc.

They are a dream to drive; although you notice slightly less available power than the conventional manual ones.

Please note this is a Citroen C matic gearbox/clutch arrangement and NOT the standard Citroen automatic gearboxes that they also made. Two totally different set ups.

In some aspects the Fiat semi automatic gearbox is the most similiar that I have found to the C matic ones (compared to normal autos). In so far as you can select your gears (completely on the Citroen; as it never overides or disobeys you like the Fiat one can with its nudge up/down slector only).


VARIATION 2
For another really clever system; there was a sort found on some Citroen 2CV's. The Trafficlutch.

This was two clutches in one. A normal manual clutch; but also a separate centrifugal clutch built in. Two clutches in one bell housing. This was done way before all this Porsche etc two clutch thing.

So you could stop at the traffic lights or junction (or whatever) without having to dip the clutch.Similarly for pulling off you could just depress the accelerator only and move forward.No need to ride the clutch pedal; "Just like" an automatic as the centrifugal clutch took up the drive.

Or you could just do power off starts using your normal manual clutch pedal/clutch; and regulate the amount of clutch spin/slip that you wanted.

Historically Citroen's technology was surely the highest. Surely if these two systems were continued and evolved....motoring today would be even better.

I also drive a 42 year old Citroen DS. In 10 years and thousands of miles of ownership I have never been left at the side of the road.

If only Citroen carried on making cars like they used too...with modern advances integrated.

Fiat and Ferrari are the "same" company after all. Fiat has all the Ferrari/F1 etc technology at its fingertips.

"All" Fiat need to do is to alter the gearbox sensor settings (or whatever is appropriate) to overcome these problems. Surely just a relatively "simple" tweak for them.

Just like some high end cars have track; sports and normal settings for traction control and ABs etc; Fiat should either wholly or as an option put in an "overide" switch or setting.

They have not quite got it right in some areas /ends.

Autoboxes used to be lacking. Changing gear at the wrong time etc etc. Wasting power. My Citroen CX auto (over 2 litres) for instance could be burnt off by a 1.1 litre manual car 0-50 mph for instance; before it got into its stride.

Yes towing in a normal auto can be very easy..... At least pulling off.....*however* sometimes you want the more of an engine braking effort than they can provide; to balance the car. At least on the older ones; so then a manual can be preferable!

Very occasionally you need to be able to wheelspin too; in order to pull the front end of the car around in a tight spot with a trailer. So manual it is for that.

I discovered on my Citroen XM v6 24 valve 3 litre; the auto box can be as "perfect" as you can get. In sports mode it changes up/down exactly when I would do if i was driving manually. So that changed my opinion of more modern automatics.

With this reason in mind too was another reason why we got the semi-auto Panda.

Someone needs to look into making an adaption if Fiat do not. I may try myself sometime. The Panda flew through its MOT yesterday too

I admit that the beach conditions for the car were slightly out of the ordinary. But the beach is a public car parking area after all.....

Please FIAT; remap the gearboxes ;-)