Jump to content
The mkiv Supra Owners Club

Engine Braking


Gough

Recommended Posts

What are people's opinions on engine braking with the autobox? I'm still getting used to my auto TT having only had it for about a month, but I've noticed shifting down from D to 2, at say 40-60mph, is very effective, as is shifting into L at sightly lower speeds. Is this something that many people do?

 

Would I be right in presuming that down-shifting at these speeds does the autobox no harm in the short and long term?

 

Thanks for your views :)

 

 

J

Link to comment
Share on other sites

Can't think of a reason why that would cause undue wear. It's got to be less than the huge change in torque put through it when the second turbo kicks in :)

 

Be careful shifting to 1st though (especially in the wet) in case you spin your rear wheels.

 

James.

Link to comment
Share on other sites

Wrecked the autobox?! :eek:

 

Thing is, surely the box shouldn't let you shift down if it has the potential to damage the transmission.

 

Oh and yes I do use my brakes, just wanted to know whether downshifting was common practice. Surely people do do this on track days don't they?

Link to comment
Share on other sites

Thing is, surely the box shouldn't let you shift down if it has the potential to damage the transmission.

 

am only giving you my personal expirience, i really dont think auto boxs are designed with harsh downshifting in mind, they take the shock upshifting cos thats what their designed to do, thats not to say they wont do it, the box will shift at whatever speed you are going if you select it, if you dont believe me try shifting from 100 to 1st and then watch the rear view mirror for bits of the box flying down the road, like i said if you enjoy doing this i think its time to buy a manual

Link to comment
Share on other sites

Originally posted by paul mac

Thing is, surely the box shouldn't let you shift down if it has the potential to damage the transmission.

 

am only giving you my personal expirience, i really dont think auto boxs are designed with harsh downshifting in mind, they take the shock upshifting cos thats what their designed to do, thats not to say they wont do it, the box will shift at whatever speed you are going if you select it, if you dont believe me try shifting from 100 to 1st and then watch the rear view mirror for bits of the box flying down the road, like i said if you enjoy doing this i think its time to buy a manual

 

The Supra owners manual states that the box will only change if the car is in the correct speed range to do so.

 

I don't fancy testing this out though.

Link to comment
Share on other sites

I always use the box to slow down, although I never go from second to first unless I'm going 'very' slow, I'm talking speed bump slow or if ive come to a stopping at a junction.

 

Always use OD off and 3rd to 2nd to bring the speed down.

Link to comment
Share on other sites

Ok, I've got a tiptronic so its slightly different but I find that if I give it just a bit of throttle before changing down, the change is not harsh at all. To be honest its not really a harsh change anyway unless you do something stupid.

 

You don't need a lot of throttle, just enough to balance the engine revs against the road speed. It can take a bit of getting used to, but once you've mastered it you'll wonder what all the fuss was about.

 

(I suppose its a bit like heel and toeing, or double de-clutching in a manual, and, yes, I do know the difference between the two, for anyone who's in a particularly pedantic mood today :D)

 

As for it being bad for the autobox, everytime you change gear, use the turbos, use the brakes, start the engine etc. its one time less that it will do it in the future. You could leave it in the garage and it will last forever or just use it and get some fun out of it.

 

Toyota don't build features into their cars to purposely make them self destruct :) If it was that detrimental, there'd be notices in the handbook, and probably stickers by the shift lever stating, "Do not shift gears manually unless absolutely necessary"

 

So the short answer is, yes it "could" wear the box out quicker, but NO, you'll probably not going to come across the problem

Link to comment
Share on other sites

Thanks for your views everyone :thumbs:

 

The general consensus seems to be that it is ok to shift down to second, but not down to first (unless travelling very slowly), and that switching off overdrive is also quite effective. Just as well really because the shift down to first isn't pleasent, and probably doesn't do the box any good at all.

 

And peter; yes you are right, I'll stop farting around....and get some UK brakes instead!

Link to comment
Share on other sites

Well I don't wanna be controversial here but i use the downshift to L in manual mode all the time. Hare into a bend that you know you have to stop in ie blinder roundabouts and slot it back from 2 to L (nothing will happen until the speed drops sufficiently for that gear to engage) I have done this from quite high mph above the L range and its just like preselecting L so when you get to the point where you can see onto the roundabout you don't have to worry about changing to the best gear for either a total stop or a slightly rolling start. I have never had it drop down in a nasty jerky fashion at all- that said I have an N/A and the ECU is different for that than the TT's

 

Just my experience with my own car

Link to comment
Share on other sites

Originally posted by Geezabloke

I use my OD and second gear for engine braking all the time. However i would not use the second to first down shift as this sounds and feels harsh unless going very slow.

 

Dropping into second at say 70 -60 works very well.:D

 

 

:flame Dev Dave

i will second that i drop the car into 2nd when im cornering hard at about 60 when im on track, it makes it much easier to step the rear end out when you feel like having a play:p

Link to comment
Share on other sites

yeah that was the other thing that bothered me, the shift from 2 to 1 requires you to operate the shift-lock button, which also made me think it's not recommended, even though the owners manual does say to use it for "maximum engine braking".

 

It's great to hear what people do and don't do though so keep 'em coming!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.