global:
I bet there are a fair few who initially passed there driving test with a manual and now drive with an automatic gearbox. That said, how do YOU descend a steep icy hill, fully loaded with an automatic gearbox?
If you’re trying to make a point that manuals are better than autos in snow and ice I’d just like to point out that snow ploughs are automatic boxes, or at least in my county they are, and they manage to cover Garrowby Hill east of York which is a 1 in 6 just fine.
As opposed to I’ve never driven an automatic truck including gritter/ploughs.
Edit to correct with the exception of a few Allison torque converter type fire trucks which like anything else would have been better and easier to drive with a proper manual box and clutch.
I guess the OP is referring to excessive engine braking being applied in slippery road conditions.That’s more an issue of the wrong ( too low ) gear being selected and incorrectly matched engine speed on downshifts.Obviously all far easier to get right using good old fashioned double de clutched downshifts and a driver who knows how to drive.
Also bearing in mind that double drive obviously reduces engine braking forces applied at the wheels by 50%.
Obviously no problems with the good old fashioned 8x4 rigid in that regard.
Sploom:
the maoster.
If a driving instructor is teaching someone,he needs to motivate them,tell them they can do it,rather than tell them only certain people are botn with these abilities,otherwise the pupil ends up believing he will never learn,when,in actual fact he could have achieved the outcome with more practice
There isn’t time on a driving course any more to teach such things, there’s already too much for the new driver to take in, its not the fault of instructors its that where old ■■■■■ like me had a 10 day driving course they’re now at 5 days or less, you can teach someone to pass a test in that time but no way can you help them explore and practice more in depth techinques.
The problem for the industry is that it the industry itself encourages drivers not to hone their skills once they have passed their test which is what generations of drivers have always done, perfect example of many deskilling decisions being the removal of manual option on automatic gearboxes, kickdown removed too the default gearbox program being ECO only, what the hell is the driver going to learn about fine tuning vehicle control with such a gearbox where (and i’ve driven with boxes programmed eco only myself, utter crap) on one downhill slip road with a vehicle programmed eco only no matter what you did (nothing, no options) the vehicle would not exceed 35mph entering the dual carriageway at the buttom of a dip with an immediate uphill once on the carriageway, driven properly ie out of eco (correctly programmed) or in manual mode the same vehicle will be doing 50 to 51mph at the same point…it doesn’t need a genius to guess the mayhem caused at that busy point in a fully loaded artic doing 35mph tops.
I personally think the HGV driving course and test should be conducted with manual gearboxes for everyone except disabled, it sadly for a rare few ended their lorry driving careers before they even started if they couldn’t cope with a truc box but dare say for most of those few who couldn’t manage a manual it saved them £thousands licencing themelves for something that was never going to work for them anyway once they entered the real world of truck driving, but thats not going to happen we are where we are.
Sploom:
the maoster.
If a driving instructor is teaching someone,he needs to motivate them,tell them they can do it,rather than tell them only certain people are botn with these abilities,otherwise the pupil ends up believing he will never learn,when,in actual fact he could have achieved the outcome with more practice
There isn’t time on a driving course any more to teach such things, there’s already too much for the new driver to take in, its not the fault of instructors its that where old ■■■■■ like me had a 10 day driving course they’re now at 5 days or less, you can teach someone to pass a test in that time but no way can you help them explore and practice more in depth techinques.
The problem for the industry is that it the industry itself encourages drivers not to hone their skills once they have passed their test which is what generations of drivers have always done, perfect example of many deskilling decisions being the removal of manual option on automatic gearboxes, kickdown removed too the default gearbox program being ECO only, what the hell is the driver going to learn about fine tuning vehicle control with such a gearbox where (and i’ve driven with boxes programmed eco only myself, utter crap) on one downhill slip road with a vehicle programmed eco only no matter what you did (nothing, no options) the vehicle would not exceed 35mph entering the dual carriageway at the buttom of a dip with an immediate uphill once on the carriageway, driven properly ie out of eco (correctly programmed) or in manual mode the same vehicle will be doing 50 to 51mph at the same point…it doesn’t need a genius to guess the mayhem caused at that busy point in a fully loaded artic doing 35mph tops.
I personally think the HGV driving course and test should be conducted with manual gearboxes for everyone except disabled, it sadly for a rare few ended their lorry driving careers before they even started if they couldn’t cope with a truc box but dare say for most of those few who couldn’t manage a manual it saved them £thousands licencing themelves for something that was never going to work for them anyway once they entered the real world of truck driving, but thats not going to happen we are where we are.
Would suggest that anything which would apply excessive engine braking to the point of drive axle lock up, regardless of road conditions, is a basic flaw in the driver training and testing system and/or auto transmission design.
Basically there is no excuse for incorrect gear selection for the situation or incorrect rev matching of downshifts.Regardless of manual or auto.Especially in the case of the worst case scenario of getting that wrong with a heavy articulated vehicle.It also doesn’t need sheet ice road conditions to know if both truck and/or driver are competent to get that right.
Is my memory playing tricks? in years gone by didn’t some tractor units in the US not apply drive axle brakes at all during normal footbrake use at least with a trailer connected? Did the same apply in Oz with US built tractors?
From what I know drive axles always had braking when using the foot valve with a trailer here in the US. What didn’t have brakes on some early tractors was the steering axle therefor eliminating the possibility of front wheel lockup and loss of steering which leads to a jackknife and of course a fiery death. In 1982 I drove for a firm that had some F model Macks and while they had front brakes they also had a lever on the dash to cut the air pressure by half to the steering axle.
When I retired in 2018 the tractors I drove all had trailer brake handles and manual gearboxes as we like to stick to the old ways.
I was warned to NOT use the exhaust brake in icy conditions. The problem is that it only acts on the driven wheels which can potentially make them lock up and start sliding sideways.
The service brake acts on all the wheels and also has the backup of ABS.
Is my memory playing tricks? in years gone by didn’t some tractor units in the US not apply drive axle brakes at all during normal footbrake use at least with a trailer connected? Did the same apply in Oz with US built tractors?
From what I know drive axles always had braking when using the foot valve with a trailer here in the US. What didn’t have brakes on some early tractors was the steering axle therefor eliminating the possibility of front wheel lockup and loss of steering which leads to a jackknife and of course a fiery death. In 1982 I drove for a firm that had some F model Macks and while they had front brakes they also had a lever on the dash to cut the air pressure by half to the steering axle.
When I retired in 2018 the tractors I drove all had trailer brake handles and manual gearboxes as we like to stick to the old ways.
Thanks for that, yes quite right, it was the steer axles which didn’t brake on some tractors, memory whats left of it playing up
Had gradually started to disappear when I started.
Just about every import trailer I collected had no brakes because everyone had ground them down to nothing rather than use their tractor brakes. I spent many a bum soaked 20 minutes underneath trailers winding them on again.
Auto V manual, I vote auto. I really think that after the clutch has engaged, it’s up to the driver to control the power to avoid slippage. More critical than clutch is the gear selection.
In all my years, I really can’t recall one big slippery ice rink of a hill. I remember in my rookie days, going out really early and the yard was icy as ■■■■. I spent the next hour and three quarters pooping myself and worrying about how I was going to descend Birdlip. When I got there, it was a breeze all the way down. I have had some slippery moments in yards oop north but I really can’t think of any helter-skelter rides down mountains and that includes Europe.
I’ve driven across the A66 loaded and empty in blizzard conditions. I found it rather exciting.
Santa:
I was warned to NOT use the exhaust brake in icy conditions. The problem is that it only acts on the driven wheels which can potentially make them lock up and start sliding sideways.
The service brake acts on all the wheels and also has the backup of ABS.
Is my memory playing tricks? in years gone by didn’t some tractor units in the US not apply drive axle brakes at all during normal footbrake use at least with a trailer connected? Did the same apply in Oz with US built tractors?
From what I know drive axles always had braking when using the foot valve with a trailer here in the US. What didn’t have brakes on some early tractors was the steering axle therefor eliminating the possibility of front wheel lockup and loss of steering which leads to a jackknife and of course a fiery death. In 1982 I drove for a firm that had some F model Macks and while they had front brakes they also had a lever on the dash to cut the air pressure by half to the steering axle.
When I retired in 2018 the tractors I drove all had trailer brake handles and manual gearboxes as we like to stick to the old ways.
Think that’s got more to do with the fact that a braked steer axle causes the nose to dive and the drive axle/s to lift by trying to rotate vertically around the braked steer axle.Followed by the trailer then trying to rotate the unit’s light loaded rear end laterally
around same.IE the definition of a jackknife.
The advantage of an unbraked steer axle is obviously way understated in that regard and when combined with twin wheel double drive in which all the braking forces at the unit create dive at the trailer and the pin and therefore more weight on the braked drives.
Many years ago had a W reg Merc1617 first lorry with an exhaust brake . It worked well slowing lorry down.One winters day i learnt a valuable lesson Was going a bit fast empty lorry came to a brow of a steep hill going down and that where the snow line was as well Quick thought exhaust brake to slow down went on the snow lost back end was all over the road as had no drive lucky nothing else on road got to the bottom of hill lucky no damage though took 3 telephone polls down Lesson do not use exhaust brake on slippery roads
Santa:
I was warned to NOT use the exhaust brake in icy conditions. The problem is that it only acts on the driven wheels which can potentially make them lock up and start sliding sideways.
The service brake acts on all the wheels and also has the backup of ABS.
Abs will also knock off the exhaust brake
A incorrectly rev matched downshift especially into a too low gear definitely facilitated by synchromesh ( auto who knows ), has more than enough potential to create an even worse situation than use of an exhaust brake in a higher gear and a correctly rev matched downshift to get it.
I do know that the semi auto torque converter Allison needed rev matching on downshifts and lifting on upshifts to stop it trying to tear the chassis and drive line apart with it’s shockingly violent shifts.I’d imagine on ice it would have been a guaranteed lock up of the drives on downshifts.The problem being that unlike a manual that obviously couldn’t be done properly with the transmission double declutched going through neutral.
I’d even argued the point with the experienced test drivers on the firm about rev matching a torque converter Allison box and later proven right by the army driving method of the same transmission in the Scammell Commander shown in a TV programme found recently.
