Gearbox

MCBladeRun

Club Member
Hi guys

Just chatting with the plasterer in work about his daughter has just passed her driving test. He brought up the fact she doesn't use her gears to slow down towards say, a junction etc.

My question is, depending on the gear box model, 4 speed/ 5 speed, is there an issue with using the gearbox for the above situation?

I didn't fancy blowing the gearbox as, that's the way I've always driven..
 

Wally

Club Member
A lot of the new driving instructors and guys teaching advanced courses are advocating this. The idea is to maintain maximum grip on the tyres when slowing down to prevent skids. As I'm sure you know front tyres only have so much grip for steering and braking and the idea is if you're changing gears as you slow down it will shock the transmission which could cause the driven wheels to skid.


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status

Well-Known Forum User
Wot a load of bull,they will only skid if you change down to quick and let the clutch out to quick sounds like the new driving instructors have been taught wrong,but then again I might’ve got too old
In ten years time manuals will be illegal because some tit will say that driving in traffic ca make yer knee ache
 

MCBladeRun

Club Member
So, if the transmission is strong enough and you don't abuse the gears / clutch you should be alright then?

I only ask out of curiosity as to know what is best for the gearbox/transmission. Obviously contact with the road is important as is control of the vehicle. But if I can avoid unnecessary stress on the mechanical parts, surely it is worth considering?

I think you boys know how to handle your own vehicles, so your driving styles will be different and that's an acceptable answer.

I think I've got a 2.8l s30 engine with a 5speed from a 280z (possibly zx) and the differential is an r180 3.36 ratio. The last owner blew the diff up. Just wondered if it was carelessness or a mechanical weakness. I've no idea what the ratio of the old r180 was.
 

status

Well-Known Forum User
When you use the gears to slow down you are getting traction which is wot you want best with red but shouldn’t be an issue with fwd
 

jonbills

Membership Secretary
Site Administrator
I've heard many times recently about the modern teaching and it does seem to make sense, but I don't think I'll change, it seems too strange not to have drag from the engine and gearbox when I'm slowing.

I would expect that the old diff blew up from too many hard starts rather than down shifts.
The early open differentials have a single pinion shaft carrying the planet gears, and the pinion is only held in the case by a single little roll pin which can shear with a lot of wheel spin.
 

Wally

Club Member
As long as you’re not dumping the clutch and have a little mechanical sympathy you'll be fine.

An easy example of tyres skidding on aggressive down shifts are on bikes. That's why they fit slipper clutches.


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uk66fastback

Club Member
I remember when my daughter was taught this - after I had initially taught her the old skool way - ie changing down ...

Much more brake wear, surely?
 

status

Well-Known Forum User
They teach em to pass their test and not to drive properly and they don’t teach the instructors as good as they did
Back in the day
 

jonbills

Membership Secretary
Site Administrator
Everything was better in the past. The future is terrible.
It's always been that way.
 

yellowz

Club Member
If you are changing down through the box is there a point where the car is freewheeling............. if so, at that point the car is not under control. That would be where I blip the accelerator to get the revs up to come down in the next gear.
Had the same issue with my son when he did his driving training test. I'm C+E (HGV 1 in old money) and got told off by his instructor!
 

status

Well-Known Forum User
I use the exhaust brake stops poss brake fade and on most hgv s there is usually more than one setting for the exhaust brake also you can set it automatically on some hgv s which I didn’t like
 

chris frizzell

Club Member
brake pad are cheaper than a new gearbox . but you should be in the correct gear for the speed you are doing. on a steep hill going down a lower gear is good to reduce the chance of brake fade. cant remenber ever being taught to use the gear box as brakes for my advanced . but how knows i see nutter doing 40mph in the outside lane on the m62 or 2 lane when there is no other traffic near them . uk driving standard is poor i dont think people take a pride in how they drive its just a chore
 

status

Well-Known Forum User
I wasn’t taught either in when I took my advanced and I don’t think it was ever taught in any driving lessons ,it’s just one of those things a lot of us picked up years ago and yes the driving standards are really bad with too many idiots taking too many chances as there are too many distractions
I think they even have using a sat nav as part of the test now which is a distraction in itself but when you consider a good proportion of the younger generation haven’t much or any common sense then I can see why it’s easier than using an A-Z or road atlas
 

toopy

Club Member
An automatic sequential gearbox (Audi DSG for example) goes down the gears as you slow, if I'm on a steep hill and on the brakes it will often drop down to the next lower gear earlier than normal to assist in a controlled decent! so why not the same in a manual.
The only time i don't go through atleast one gear while slowing down in a manual, is if on the rare occasion Ive had to pull up sharp.

Slowing down without using the gearbox sympathetically is completely alien to me, I don't get it! If im in 4th i will almost always drop to 3rd before then maybe stopping and going to 1st, but often enough 2nd as well.
Free wheeling while braking feels like im not entirely in control, i guess it's hard to explain to people if you've been taught not to use the box!!

Maybe that's part of the reason why so many youngsters have accidents, they aren't taught how to brake and drive at the same time! :D
 

toopy

Club Member
So, if the transmission is strong enough and you don't abuse the gears / clutch you should be alright then?

I only ask out of curiosity as to know what is best for the gearbox/transmission. Obviously contact with the road is important as is control of the vehicle. But if I can avoid unnecessary stress on the mechanical parts, surely it is worth considering?

Why would going down the gears cause anymore wear than going up the gears?!
 

MCBladeRun

Club Member
Why would going down the gears cause anymore wear than going up the gears?!

Well, the engine isn't doing the work, as I'd imagine going up the gears is a slower process and the engine is pushing this along.

Whereas the moment you're gearing down to stop etc, the engine isn't doing the work, and is at the mercy of the speed + transmission + gear selected?
 

Rob Gaskin

Treasurer
Staff member
Site Administrator
Yep modern thinking is to use the brakes without changing down. My kids were taught that. I change down as I do when slowing for a bend or obstacle e.g. parked car so that I'm in the correct gear for driving round it.
 

SeanDezart

Well-Known Forum User
I was taught that brakes and for braking, gears are for driving.

Normal road driving, I'll brake and then select the gear most suitable for the road speed and conditions.

I challenge anyone to drive more economically than I over a 1000km test.

Track-days are different :boxing: and if I'm pulling more than 10mpg then I aint trying hard enough.:D
 
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