I have decided to post this here rather than in the tech section as all need to know;
RE: new motor homes/ vans & trucks etc;
Transmissions; manual shift or auto shift;
After several conversations during this trip with the owners of such vehicles, it is obvious that people do not understand the function of these transmissions, neither do sales people who inform people that they are auto's.
These transmissions are NOT auto's, as in a fully auto car, they are a manual transmission with a AUTOMATED clutch & gear shift system.
This means that when a gear shift is activated a computer controled automated system does the clutch & gear shift operation for you.
The problem that is happening is clutch burnout.
Reguardless as to which way you wish to drive, either changing manually or in the auto mode.
If you are sitting at the lights, or just waiting for some one or what ever, if you sit there with the transmission engaged it is the same as being in a full manual & sitting the with your foot on the clutch waiting to go, as done by many drivers & is wrong.
You need to netualise the transmission when stoped, when ready to move re engage & move off. This will save you many dollars in clutch replacements.
Hope I have explained it in a way that people can understand, if not please ask for more info.
Safe travells.
JC.
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Be your self; there's no body better qualified ! "I came into this world with nothing , I still have most of it"
Thanks for that justcruisin. Although Myrtle is only an old manual I have a habit of sitting at the lights with my foot on the clutch which I must stop doing.
HW with a manual if you've got the clutch pedal fully depressed that's fine, what damages the clutch is riding it, that means letting it out to slow or keeping the pedal partially depressed whilst moving...
HW with a manual if you've got the clutch pedal fully depressed that's fine, what damages the clutch is riding it, that means letting it out to slow or keeping the pedal partially depressed whilst moving...
Gubby, you are correct in what you say BUT holding the clutch peddle down is also running thre thrust bearing all the time ,same as resting the foot on the peddle when driving, this wears the bearing out , will become dry, then noisy & will seize up, than destroy the pressure plate.
Its all part of the same package, continual wear of all parts.
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Be your self; there's no body better qualified ! "I came into this world with nothing , I still have most of it"
Justcruisin I'm not going to get into a debate over this, yes when the clutch is fully depressed the thrust race (Bearing) is being used, that is what it is designed for, that is why it is called a bearing.
in your original post you said "The problem that is happening is clutch burnout."
When the pedal is fully depressed the clutch plates are completely disengaged. ie No wear to the clutch or pressure plates.
My advice to you Marj is don't take what we say on here as fact, ask your mechanic that you can trust..
Over the years I developed the habit of going to neutral while at lights or waiting to move off. It takes only a second to engage a gear when the lights go green or it's okay to move on. I also use gears to slow down before I actually use the brakes. It's much better for the vehicle in the long run. I love manual gear box, and I've never worn out a clutch or brakes on any of the vehicles I've owned. With the Landcruiser it's much better to slow down early, using the gears to slow down before calling on the brakes. It's a heavy vehicle. It's also a valuable habit when towing. Not every road is straight and flat. For every up there's a down, and for every down there's an up, so it's wise to be absolutely familiar with your vehicle's capabilities and standards of wear and tear.
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20ft Roma caravan - Mercedes Benz Sprinter - SA-based at the moment. Transport has no borders.
Management makes the decisions, but is not affected by the decisions it makes.
Sorry.as a mechanic and a driving instructor for a total of forty plus years I could never agree with this.
If you take the car out of gear at the lights, you are in fact wearing the clutch out nearly twice as fast.
Why?
Because you are engaging the clutch twice, this means that it is meeting the flywheel and pressure plate surface in friction mode unnecessary. You are also placing the thrust bearing (that's the one, you are worried about wearing out) under stress twice.
Also, at the traffic lights, when everyone else is moving, you are putting the vehicle in gear? I think that's called "obstructing the flow of traffic."
"Auto" are precisely that. AUTO.
Even Semi-auto are meant to be left in "D" at the lights or in heavy traffic situations.
If you want to get in a discussion on the "old" style hydraulic autos, the newer electronic autos or the DSG gearboxes, so be it.
Each gearbox is different, but they are all "auto."
Dusty
Would be very interested in the brand of vehicle you are reffering too?
This could provide a whole new outlook on the subject?
-- Edited by Landfall on Sunday 30th of October 2011 10:26:57 PM
Whoo .... controversy perhaps but here goes ... However, if you are suggesting that, with a modern (2000 or newer) automatic transmission vehicle, you should shift it into neutral when stopped at traffic lights to minimise wear in the components, I think you probably should get some more up-to-date research.
Modern auto transmissions will wear at an appreciably greater rate if constantly moved into and out of neutral in situations such as sitting at lights.
Modern transmissions are designed to maintain correct auto-trans-fluid circulation by being retained in an 'active' gear - D, 1, 2, 3, R etc. so that there is no 'take-up' each time. Leaving the box in neutral is worse than putting it into P when stopped.
Into and out of P also creates stress/wear than any other position.
I am more than willing to hear/see/read "modern research" that disputes my comments.
And manual transmission - clutch pedal fully depressed (out), pressure and clutch plates are separated - minimises wear. Thrust bearing operating but doing what it is supposed to do.
Clutch in the "in" position - foot completely off - pressure plate and clutch plate remain engaged and some friction is maintained - thrust bearing inactive. Potentially more wear on clutch and pressure plates.
Foot slightly maintaining some (any) pressure on clutch pedal - whether moving or stopped - causes excessive wear to pressure plate, clutch plate and thrust bearing.
Therefore, keeping foot completely on clutch (depressed) on floor is probably the best of the above for manual transmissions.
Cheers
John
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2006 Discovery 3 TDV6 SE Auto - 2008 23ft Golden Eagle Hunter Some people feel the rain - the others just get wet - Bob Dylan
I have always been told never to ride the clutch (under pain of death) and always use the gears to slow down. I was given many hours of teaching (or very loud talking) until I got it right by my husband when he was teaching me to drive his most precious possession. It was never a problem to have one foot on the clutch fully depressed and one on the break. He was a mechanic and I, like CG have never burned out a clutch.
Are/were we talking about those cars with the optional/psudo manual ability like my current Falcon? I think there may be a case for putting it in neutral when stationery. I can uderstand the extra wear this might put on clutches when this is not done..
---SNIP--- It was never a problem to have one foot on the clutch fully depressed and one on the break. He was a mechanic and I, like CG have never burned out a clutch.
Are/were we talking about those cars with the optional/psudo manual ability like my current Falcon? I think there may be a case for putting it in neutral when stationery. I can uderstand the extra wear this might put on clutches when this is not done..
Gday...
The auto trans in the current Falcon is the type of auto I was referring to ... modern auto trans should be left in D when stationary at lights etc - they are designed to live there. Constantly taking them into and out of D, particularly in city driving, is killing the box.
And also as others have said - when stationary at lights with manual trans - one foot firmly on the brake and the other with the clutch on the floor is a very good (best) way to minimise problems.
And as CG and others say - when towing a load with a manual trans, it is wise to use the gears to assist the brakes to slow, and control, the load to come to a safe stop - or controlling the outfit on downhill runs - but making sure that your right foot covers the brake while you change down to the lower gear so you maintain speed and don't have the outfit run away.
I am not sure that when driving the vehicle when not towing (even a heavy 4X4) it is as wise to use the gears to slow the vehicle - lots of changes means the potential for additional (unnecessary?) wear. There are heaps who disagree - so I am not gonna insist on that.
Cheers
John
-- Edited by rockylizard on Sunday 30th of October 2011 10:56:52 PM
-- Edited by rockylizard on Sunday 30th of October 2011 10:57:26 PM
-- Edited by rockylizard on Sunday 30th of October 2011 10:58:23 PM
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2006 Discovery 3 TDV6 SE Auto - 2008 23ft Golden Eagle Hunter Some people feel the rain - the others just get wet - Bob Dylan
This is what I love about this forum. On so many of the others, at this point in this kind of conversation, there would have been 2 tantrums, 3 people calling other people names, and at least one member threatening to never return. No such ego or immaturity here. I love it!
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Not grey yet, but if I keep playing with campervans, I suspect that I very soon will be!
Interestingly, The Department of Transport and Licencing recommend that when stationary at the lights in a manual vehicle, the vehicle be left in 1st gear with the clutch fully depressed, the handbrake on and the right foot over the accelerator ready to move off.
The handbrake is on, in case someone runs up the back of you, pushing you forward.
Have some trouble coming to terms with this method, now that some manufacturers are bring back the "handbrake" to be "foot" operated again. This correctly being called a "parking" brake. e.g. Mercedes Benz
I do know of a couple of driving instructors that teach the car (manual) in nuetral when stationary at the lights or in heavy peak hour traffic.
Please be aware folks, we all seem to be talking about vehicles of different vintages and technologies here .. regardless of the experience of anyones long-standing in the field of auto mechanics or rocket science, there are considerable differences that need to be addressed .. "auto" & "automated" gearboxes are very different .. so, if you find it difficult to follow the comments in this thread, then as said earlier, go to your own sources that you are comfortable with ..
We are lucky to have the input we get on so many topics ..
Hmmmm, obviously time for me to start going to the gym again.I am sure I could not hold the clutch pedal fully depressed for the length of some traffic light sequences that I have encountered!!. Maybe I travel the wrong roads and was taught antiquated methods, but they have stood me in good stead over the 50 some years that I been driving. Never a burnt clutch nor non functional auto. This includes old and new vehicles of many makes, models and varying tasks. For me with an auto, leave it in drive, park brake on. With a manual it's out of gear and park brake on and keep your eye on the traffic signal. So simple!!!!
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Take only your memories, leave only your footprints
Automatic transmissions are engineered to be driven in drive, including decelerating traffic, stop lights and so on. The torque converter is engineered to slip in those circumstances.
There are risks in changing to neutral when slowing (no-one here would do that surely) - the engine braking effect is lost, control of the vehicle is also lost and there is also the possibility of missing neutral and hitting another gear (R?).
Similarly at lights control of the vehicle is reduced if it is not left in drive as it should be. It would for instance be impossible to take quick avoiding action if required. Also, when the light changes to green, it is easily possible to rush and increase throttle that margin too soon after D has been selected, before the pressure has built up in the transmission for drive, resulting a a thump. Or worse, increase the throttle before the shifter is moved to drive.
There is no saving in fuel, nor in wear from shifting to neutral in the instances given.
Just to add, I have restricted my comments to the usual private vehicle most people use including 4WDs. If there are unique set-ups in larger commercial vehicvles chat with the dealer.
-- Edited by johnq on Monday 31st of October 2011 09:38:40 AM
I have a question sort of on the same subject, I'm talking about a manual Toyota Landcruiser (1994) clutch operation, is it ok to hold the clutch pedal down when starting the car?
Holding the clutch down when starting up has always been automatic for me in 50 years of driving, maybe it is no longer needed but I have sat alongside driver who don't and have witnessed a start with the car in gear, now how much damage does that do and how dangerous is that situation. Starting with the clutch depressed is a safe and logical driving practise.
As we are starting to look around at a new, 2nd hand tug for our retirement, whats the best towing vehicle for a medium size caravan (twin axle) ?
I knew that ,Sweetie Pie. Don't you like the smell of a burning clutch?no sense of humour eh........................Good sensible information,I am sure it will be well received by anyone who has not much experience with Man/Auto Trans.Now do you have any tips to make my Crystal Set pick up FM stations.I have tried various cats whiskers but not had much luck.Also the sets do not work underwater.My main complaint about Crystal sets is the fact that nowhere can I find a place to plug into 240 power.Can you help?.
justcruisin01 is not talking about automatic or manual gearboxes as such, you will find he is talking about the automated manual transmissions that are fitted to some trucks, Rod
justcruisin01 is not talking about automatic or manual gearboxes as such, you will find he is talking about the automated manual transmissions that are fitted to some trucks, Rod
Rod, I did ask in my first post, "What brand of vehicle are we talking about?"
It does help when we get an answer!
Although, it has ended up a very interesting discussion anyway.
Dusty
-- Edited by Landfall on Monday 31st of October 2011 08:37:40 PM
Just got home from an 8,000Km tour about the place.
Had a clutch (or maybe driver ) scare around 150km east of Broken Hill.
I never tow the 2.4ton van with my old (250,000km) 1995efi petrol Patrol, in 5th gear... except for this particular day.
When I tried to change down to my usual 4th gear because of a rather strong head wind, aren't they all, I couldn't declutch. Buggar!!
I used engine revs to knock it out of gear & then engage 4th without the clutch & away we went with me developing all sorts of emergency contingincies as we went not so merrily along.
As we got close to Broken Hill I tried the clutch again & guess what, it worked as it did for the next 4,000km. Even the very occasional short scream from the thrust bearing, fixed itself a few weeks later.
Talked to lots of 'experts' with no real clues to the problem.
I have come to the conclusion that a floor mat had ridden up under the pedal preventing it from fully depressing. This coupled with my stiff left leg after several hours driving lead to the rather panicked conclusion that the clutch was faulty.
ps.. back on topic, at stop lights et al, I always engage 1st gear & sit with clutch fully depressed & foot break on. Only if the stop looks to be being prolonged do I go to neutral & put the handbreak on. Just by habit I think.
Oh yes.. I always start the motor with the clutch depressed. Maybe someone once a long time ago told me that it took less battery power to turn the motor over this way & we always had dickie batteries in those days .. who knows .. just habit I guess.
-- Edited by Cupie on Monday 31st of October 2011 07:18:31 PM
Holding the clutch down when starting up has always been automatic for me in 50 years of driving, maybe it is no longer needed but I have sat alongside driver who don't and have witnessed a start with the car in gear, now how much damage does that do and how dangerous is that situation. Starting with the clutch depressed is a safe and logical driving practise.
As we are starting to look around at a new, 2nd hand tug for our retirement, whats the best towing vehicle for a medium size caravan (twin axle) ?
I do still actually remember the driving instructor pulling me up on this, even though the car was in neutral. and also the testing officer back in QLD back in the early 70's. Their preferred method was handbrake on, check car in neutral and then start. I still do it anyway though, better to be sure even if you have put the transmission in neutral.
The main purpose of the handbrake is actually for making spectacularly sharp turns on slippery surfaces.
For those that cant read I would like to know please when & where I discussed a automatic transmission;???? The moving of it in & out of drive, you must have been some where else.
The topic in discussion is the automated manual system , this is used in many vans that are used for motor homes, mercs, iveco, fiat, transit etc . it is also in trucks as well.
In saying that holding the clutch in the disengaged position the bearings are doing what they are desighned to do, correct to a point. Many people do not keep cars long enough to see the end result, some other poor bugger ends up with it.
The prolonged run time of these bearings compared to that of a normal gear selection quite often results in premature failure of the bearings. I would estermate that 50% of the replacements I have done for customers over the past 30+ years in both cars & farm tractors has been due to bearing failure.
When a thrust bearing failes it destroyes the presure plate diaphrame spring. When a spigot bearing fails it wears a grove in the gearbox input shaft, if this is not replaced or repaired when a new clutch assy is fitted then you end up a misaligned clutch plate& out of balance.
Not to mention the hydraulic cylinders that may be getting a bit the worse for wear & starting to have leak back in the master &/or a leaking in the slave cyl, this slowly re engages the clutch to a point of drag, more wear.
How about the cable operated systems, that often dont get checked & readjusted in a service. You may now have a bearing that is running all the time with out having your foot on the peddle. What about all those bad desighns where the cable is anchored in the fire wall ,fatigue & crackes untill the section breaks out. Theres more drag & wear , but you are holding your foot on the floor to stop this, hows the left leg going by now? a little tired, keen to go ,starting to creep, oooops your not on the floor any more, more drag but you havent noticed because you other foot is on the brake.
If you still think I have it wrong then do it your way, the work shops are waiting for you & I'll just go back to watching the idiot box instead of wasting my time & efort trying to share information that could save you hundreds, maybe thousands of dollars.
Its your call.
-- Edited by justcruisin01 on Tuesday 1st of November 2011 09:55:14 AM
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Be your self; there's no body better qualified ! "I came into this world with nothing , I still have most of it"
HW with a manual if you've got the clutch pedal fully depressed that's fine, what damages the clutch is riding it, that means letting it out to slow or keeping the pedal partially depressed whilst moving...
Gubby, you are correct in what you say BUT holding the clutch peddle down is also running thre thrust bearing all the time ,same as resting the foot on the peddle when driving, this wears the bearing out , will become dry, then noisy & will seize up, than destroy the pressure plate.
Its all part of the same package, continual wear of all parts.
most madern vehicles have a constant running thrustbearing unlike the older vehicles that had about 1/16 air gap
HW with a manual if you've got the clutch pedal fully depressed that's fine, what damages the clutch is riding it, that means letting it out to slow or keeping the pedal partially depressed whilst moving...
Gubby, you are correct in what you say BUT holding the clutch peddle down is also running thre thrust bearing all the time ,same as resting the foot on the peddle when driving, this wears the bearing out , will become dry, then noisy & will seize up, than destroy the pressure plate.
Its all part of the same package, continual wear of all parts.
most madern vehicles have a constant running thrustbearing unlike the older vehicles that had about 1/16 air gap
cheers
blaze
A constant running bearing does not run at full speed, it is only being brushed by the presure plate & only turns a little by comparasion.
It also does not carry any load at this point in time.
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Be your self; there's no body better qualified ! "I came into this world with nothing , I still have most of it"
