I have a couple of vehicles with manual transmissions- a Yaris and a Ranger. On both of them, reverse gear is higher than first gear, high enough that slipping the clutch is usually necessary to keep the speed down when backing up.
Is this just a manufacturer’s ploy to sell more clutches and labor? Who needs a reverse gear faster than first gear? Is there some good reason for reverse being higher than first gear?
I don’t think it’s any conspiracy to sell clutches or anything like that.
I think on a lot of older four speed transmissions first gear and reverse had the same gear ratio, or were at least close to that. On a five speed, first gear is usually geared low enough that if you had to go any distance in reverse with that gear ratio it would be a royal pain. Picture having to back up on a driveway that’s about a hundred yards long (one of my friends has one of these). On the other hand, if you are backing out of my driveway (which is much shorter) slipping the clutch is no big deal and certainly isn’t going to dramatically reduce the life of the clutch. A higher gear ratio for reverse makes a lot of sense to me.
I think it’s also to give you finer control over the car, which can be critical while reversing, and reduce the risk of stalling.
I think you misunderstand the OP; he describes reverse gear moving the car at a higher speed than first gear.
Off the cuff I am guessing that the ratio for first is chosen to allow the vehicle to get moving under maximum load conditions without unduly straining the drive train. Since reverse is used much less often, and there is only one reverse gear, I would guess the ratio is chosen to be the best compromise between easily moving the fully laden vehicle and moving at a reasonable speed.
However I can’t recall a vehicle I have owned in which reverse seemed to be a higher ratio than first.
Out of curiosity I looked up the ratios for some of the older trucks I once owned. Borg Warner transmissions had a significantly lower reverse ratio than first (this is what I was recalling), while newer ZF transmissions have a marginally higher reverse ratio than first.
Perhaps better traction in snow and ice conditions when you might chose to start in 2nd going forward.
Right, and a higher gear will help the driver avoid sudden lurches when in reverse. Just like when you try to start forward in 2nd gear.
You’re quite right. I read that as “geared at a higher ratio”, which does seem to be the case for most cars that I’ve driven, but that’s quite a small list. The OP is saying the opposite.
Clearly more research is required at a point when I have a bit more time.
Between the town I grew up in and one of the regional cities (Rotorua), there is a very steep, fairly long hill. According to family lore, when cars were less powerful than modern cars (minis, austins, morris minors, ford prefects …) people would have to reverse up Tikitere Hill because that was the lowest ratio in the gearbox.
Of course, this was the same family lore that suggested that if you were coming from Rotorua fast enough, you could get air as you crested the hill on to the down slope. You could certainly unweight the car if you went fast enough, but actual air — I’m not convinced.
However, I have tried to drive up that hill in torrential rain, and had real traction problems in a modern 2 litre saloon. It was quite some hill.
Si
OK, here’s the numbers for my cars-
2008 Yaris 5 speed manual:
1st gear, 3.545 : 1
Reverse, 3.250 : 1
2009 Ford Ranger, 5 speed manual:
1st, 3.905 : 1
reverse, 3.391 : 1
1977 Mercedes 300D, 4 speed automatic:
1st, 3.98 : 1
reverse, 5.47 : 1
The Benz backs up really slow, maybe too slowly, but a lower reverse (higher numerical ratio) in the other two would be nice.