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dobbo
I've just bought an RX300 SE-L (54 Plate).

I've looked around this forum, and seen that a number of people have had problems with the parking break.

When I was test driving one from a Lexus dealer, the salesman told me that he has had a number of RX's and always leaves them in 'park' on the gearbox and generally doesn't bother with the parking break.

Is this true, is the gear box sufficient, or should you always use the parking break? I have never owned am automatic before, so I don't know how good they are for keeping cars in place.

Ta
Parthiban
The car will not go anywhere in park so it should be perfectly secure - however I don't like the idea of the car being held that way when auto boxes are so expensive to replace, so I would always stick the parking brake on when the car is parked up.
ihpj
Well (IMHO) the parking brake is for that: parking. If it isn't used, then come MOT time the car will fail [for handbrake use] and you will have to get it sorted. Use it when parking and now again to keep efficiency and you'll have no problem.
The Editor
Never used the parking brake...... Never have never will.

As I said in my other post:......

That's what 'P' is for on the selector :hehe: :hehe: :hehe:

Have had automatics for going on 16 years and 6 cars and have never once used a parking brake. 'P' locks the gearbox and it aint going anywhere with it in that position!

Yes, yes... before the human rights brigade get on my case and say how dangerous that is and how the Devil will emerge from Hell and engulf me in flames of wrath, and how if I do this my gearbox might explode into a million pieces and cause oil to leak out which will set off a pollution disaster of biblical proportions and kill all the polar bears and tilt the earth of it's axis and we will all freeze to death in a nuclear winter....... I don't care !!

Have never had a problem, with mine, anyone elses or hire cars. What was the question again?... Oh yeah... parking brakes.. Nope.... don't use em
Rich OB
Lol at The Editor!

I use the hand brake. Out of habit I suppose, first auto I've owned. And I always feel just using P hurts the motor. Especially when it rolls forward to a jolt before it locks.
dobbo
[quote name='The Editor' timestamp='1309207206' post='757402']
Yes, yes... before the human rights brigade get on my case and say how dangerous that is and how the Devil will emerge from Hell and engulf me in flames of wrath, and how if I do this my gearbox might explode into a million pieces and cause oil to leak out which will set off a pollution disaster of biblical proportions and kill all the polar bears and tilt the earth of it's axis and we will all freeze to death in a nuclear winter.
[/quote]

I think I might need to upgrade my insurance, I'm not sure I'm covered for that.
steve2006
To quote

"The parking pawl locks the transmission's output shaft to the transmission casing by engaging a pawl (a pin) that engages in a notched wheel on the shaft, stopping it (and thus the driven wheels) from rotating.
Most vehicle manufacturers and auto mechanics do not recommend using the transmission's parking pawl as the sole means of securing a parked vehicle, instead recommending it should only be engaged after first applying the vehicle's parking brake. Constant use of only the parking pawl, especially when parking on a steep incline, means that driveline components, and transmission internals, are kept constantly under stress, and can cause wear and eventual failure of the parking pawl or transmission linkage. The pawl might also fail or break if the vehicle is pushed with sufficient force, if the parking brake is not firmly engaged. Replacement can be an expensive operation since it generally requires removing the transmission from the car.
It is highly inadvisable to use the parking pawl to stop a vehicle in motion. Modern parking pawls are connected to a safety mechanism that prevents the pawl from engaging unless the vehicle is stopped first. The pawl mechanism is generally not strong enough to stop a vehicle in motion, if it engages at all. Under that much stress, the pawl may simply break off in the transmission, leading to costly repairs."
The Editor
[quote name='steve2006' timestamp='1309254393' post='757427']
To quote

"The parking pawl locks the transmission's output shaft to the transmission casing by engaging a pawl (a pin) that engages in a notched wheel on the shaft, stopping it (and thus the driven wheels) from rotating.
Most vehicle manufacturers and auto mechanics do not recommend using the transmission's parking pawl as the sole means of securing a parked vehicle, instead recommending it should only be engaged after first applying the vehicle's parking brake. Constant use of only the parking pawl, especially when parking on a steep incline, means that driveline components, and transmission internals, are kept constantly under stress, and can cause wear and eventual failure of the parking pawl or transmission linkage. The pawl might also fail or break if the vehicle is pushed with sufficient force, if the parking brake is not firmly engaged. Replacement can be an expensive operation since it generally requires removing the transmission from the car.
It is highly inadvisable to use the parking pawl to stop a vehicle in motion. Modern parking pawls are connected to a safety mechanism that prevents the pawl from engaging unless the vehicle is stopped first. The pawl mechanism is generally not strong enough to stop a vehicle in motion, if it engages at all. Under that much stress, the pawl may simply break off in the transmission, leading to costly repairs."
[/quote]

PAH !!.... Like I said... destruction of the world is nigh !..... My gearbox will explode and blind people six streets away, the economy will go into global meltdown and the next door neighbors budgie will die !!
Boxbrownie
Dobbo, it is perfectly acceptable to leave your vehicle in the transmission park position, this facility was first engineered in the USA primarily to aid the wheel parking brake when vehicles were to be left parked on steep inclines (wheel parking brakes can be notoriously inefficient, especially when parked hot and left to cool down), on San Fransisco hills you will see front wheels turned into the kurb also to aid vehicle security on the inclines, but that is highly frowned upon by tyre manufacturers also!

Bottom line is the trans brake is fine if engaged when stationary and parked normally.....for example if parking on a moving platform (ferry, train, transporter etc) then engaging the wheel park brake firmly is absolutely required due to the rocking motion of the platform, this could indeed cause a problem if there was a sudden and violent jolt.

And never try to engage the trans brake whilst the vehicle is in motion, not even very slowly as this could in fact damage the parking pawl inside the transmission.

Always use the trans park normally and all will be fine.....I personally always use just the trans park brake, and engage the wheel park brake about once a month or so just to keep the mechanism working freely, this will ensure it'll pass the DoT tests without problems of siezure and ineffeciency as the shoes will be like new.

As for Polar bears....really cuddly, but never eat thier liver....it'll kill you :lol:
dobbo
[quote name='Boxbrownie' timestamp='1309289509' post='757471']
Dobbo, it is perfectly acceptable to leave your vehicle in the transmission park position, this facility was first engineered in the USA primarily to aid the wheel parking brake when vehicles were to be left parked on steep inclines (wheel parking brakes can be notoriously inefficient, especially when parked hot and left to cool down), on San Fransisco hills you will see front wheels turned into the kurb also to aid vehicle security on the inclines, but that is highly frowned upon by tyre manufacturers also!Bottom line is the trans brake is fine if engaged when stationary and parked normally.....for example if parking on a moving platform (ferry, train, transporter etc) then engaging the wheel park brake firmly is absolutely required due to the rocking motion of the platform, this could indeed cause a problem if there was a sudden and violent jolt.And never try to engage the trans brake whilst the vehicle is in motion, not even very slowly as this could in fact damage the parking pawl inside the transmission.Always use the trans park normally and all will be fine.....I personally always use just the trans park brake, and engage the wheel park brake about once a month or so just to keep the mechanism working freely, this will ensure it'll pass the DoT tests without problems of siezure and ineffeciency as the shoes will be like new.As for Polar bears....really cuddly, but never eat thier liver....it'll kill you :lol:
[/quote]

Thanks Mr Brownie, I think I'll take your advice.

As for the polar bear, if you tried to eat my liver I'd chuffing kill you too..! (actually I knew that, it's to do with a vitamin D overdose, as they have to store loads of it in their livers for the winter months, due to lack of sunlight). So there you go, not only have we learned about parking breaks and transmission breaks, we have also learnt an utterly useless fact about polar bears.

Thanks to everyone.
steve haley
[quote name='steve2006' timestamp='1309254393' post='757427']
Most vehicle manufacturers and auto mechanics do not recommend using the transmission's parking pawl as the sole means of securing a parked vehicle, instead recommending it should only be engaged after first applying the vehicle's parking brake. Constant use of only the parking pawl, especially when parking on a steep incline, means that driveline components, and transmission internals, are kept constantly under stress, and can cause wear and eventual failure of the parking pawl or transmission linkage.
[/quote]
30 years 7 automatics and 1 manual.
Never sold a car under 80k and never used a parking break on the autos except on ferries/auto rail and v steep hills (jic)
Blew a gearbox seal racing a porche down the autobahn 15 yrs ago but that was the only gearbox problem I have ever had and I am pretty sure that was bad maintenance as opposed to not using the parking brake!
Have always set it on ferries as I haven't liked the idea of it rocking on the box and the lexis rocks a bit more than most.
Rgds
Stephen
Parthiban
I think the end result we can take from this is that it isn't recommended but isn't necessarily going to cause any extra damage. I'd be interested to know from those who never use the parking brake what's the longest they owned one of those automatics though, because I wouldn't expect an autobox to fail after just a few years (high mileage is not an indicator)

In fact I don't think anyone could argue that it doesn't cause extra wear, it is only whether the wear is relevant or not.
Duncan Roberts
using the parking brake (note spelling) is surely a legal requirement not a choice?
The Editor
[quote name='Duncan Roberts' timestamp='1309793330' post='757830']
using the parking brake (note spelling) is surely a legal requirement not a choice?
[/quote]

I think you'll find stopping at red traffic lights is a legal requirement as well but it seems not many people bother any more (especially if they're on a bicycle !)

Since our police force is now reduced to a couple of bobbies that patrol an area the size of Lincolnshire I haven't seen too many plod go round a car park in say Alton Towers or a branch of Ikea and then systematically rock each one to determine whether the parking brake has been applied in each case.

(I'm still worried about next doors budgie though !!)
Boxbrownie
[quote name='Duncan Roberts' timestamp='1309793330' post='757830']
using the parking brake (note spelling) is surely a legal requirement not a choice?
[/quote]
From the highway code

"Generally, if the vehicle is stationary and is likely to remain so for more than a couple of minutes, you should apply the parking brake and switch off the engine to reduce emissions and noise pollution."

Generally does not seem to indicate it is a legal requirement, it would be good to clarify though.
PQuist
I always use the hand brake as advised by Lexus. I park on the hill and was asked to put the gear in Neutral, press the handbrake to take the weight of the car and finally push the lever to P.

This helps to maintain the life span of the gear box as the weight of the car does not rest on the gear box
LexIS200Sport
[quote name='PQuist' timestamp='1310731082' post='758751']
I always use the hand brake as advised by Lexus. I park on the hill and was asked to put the gear in Neutral, press the handbrake to take the weight of the car and finally push the lever to P.

This helps to maintain the life span of the gear box as the weight of the car does not rest on the gear box
[/quote]

I do the same too in my X-Trail automatic. It's just my personal belief that the park brake should do the primary job of holding the vehicle still, over the transmission locking mechanism.
TigerFish
I always use the park brake, which is more a habit from having more manual cars in the past than anything else. Whether it is neccesary or not doesn't really matter. As it is present, and it is what it is intended for, I don't see why anyone wouldn't use it. I put the gearbox in park because I am parked, I put the park brake on because I am parked.
Mike evans
Not using the parking brake isn't a deal breaker for the transmission.
Yes, it can leave constant load on the transmission components, but this is minor in comparison to the loads it sees in use.
Long term parking on a hill would not do the transmission / power train mounts much good.
But mechanically, there shouldnt be an issue.

Problems have happened, with linkages breaking, and parking pawls not fully engaging.
Rare, yes, but they have happened.

I would recommend using the parking brake.

It's good practice, and keeps the parking brake components from seizing.
Parking brake seizing is common on auto vehicles simply due to lack of use.
Annoying at mot time...
Steve
I live on a hill so always use the parking brake, just feels the right thing to do!
wheelerd45
I have driven autos for 20years. I never leave the parking brake on on the flat but use it on hills or ferries. My last car prior to the RX was a Toyota LC5 land cruiser which I had for 7 years. I had no trouble with either the gear box or the brakes. I have always felt that leaving the parking brake on for long periods will cause 1) the cables to stretch & 2) the brakes to lock on, the same applies to my caravan, the parking brake is left in the off position once the legs are down, I have seen too may vans with locked brakes in the past.
Mike evans
Agree with you.

If being left for a long time, trailer brakes can and do lock on. They are usually not designed well, and dont often see much use.
Exactly the same occurs on cars when the parking brakeisnt used often.

If leaving a car or trailer for a long time, also consider puttingit on axle stands to get the load off the tyres.


For a car in everyday use, i reccomend using the parkng brake. Simply as good practice wether on a hill or not.

Ive been working with autos, and auto gearbox design for years, and have never witnessed a failure in park.
The parking pawl is designed for large loads, failure is unlikely, once it's locked in.

You can make your own mind up about parking on the level, and whether or not to use the parking brake.
My opinion is that its good practice, and a good habit to get into, and a good thing to teach anyone who has an auto.

From experience, seizure due to lack of use happens more often than parking brake components wearing out.


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