Why can't American trucks have synchronized transmissions?

Yeah, I have seen guys back pocket doubles loaded with bricks into places like that, I admire those that can, I havent got a hope.

I like crash boxes because they have less moving parts, tend to cope better with missed or poor gear changes and abuse, and are cheaper to repair...although I could be wrong on that one as its a long time since I've worked on a Euro box.

We are seeing many auto shifts in Aus now especially the Eaton auto-shift but the main driving force behind it is a cronic driver shortage, the fact is you need less skill to drive an auto, and drivers with less skills are getting very common these days, its also less daunting for women, Linfox especially is trying to get women drivers by buying autos.

BTW. If you really want a tuff gearbox, buy a Mack triple countershaft box, a lot of heavy haulers around here use them with C16s and hub reduction diffs, they stand up very well and have no sycros, weigh quite a bit though.

 

actually, where do you think all those AMT get tested?

they simply dont last with the loading we put on them, otherwise they would be everywhere..

missing a gear when dragging 150+ tonnes is catastrophic, but the amt simply dont play with that weight.

 

I did tranny conversions on Volvo. First of all synchronizer tranny requires clutch servo, else your left foot will be bigger and left leg will be thicker.

Clutch servo fits not all US trucks, becouse it requires hydrolic clutch. Installing hydrolic clutch to Century class is a 1-2 days deal.

It is not all. not all drivers here like to drive truck with full synchro tranny. It is habit issues.

US transmissions are more reliable, smaller and lighter. EU transmisions lets you shift like 2-5-7-8 using not all gears with less delay, but if you shift 2-3-4-5 -6-7-8-9.... US transmission is faster.

For me, I'd like to have 10 st eaton as very simple, reliable and easy to fix transmission. Some European transmissions like Mercedes with GS II are like an art, really reliable but it is a pain to fix it. ZF Freedom/Astronic are too complex and it is a pain to take it apart and rebuild. Twice more time then for Eaton.

 

if we make comparison of automated gearbox from 10 year old truck and compare it with today´s truck they are better and better

i also don´t like some of them for example man tga tip matic is too aggressive on clutch and with high weight it can make damage

for normal 40ton load even with smaller engines and hills and on heavy
there is almost no need for driver´s correction of gear terrain

mercedes slt (for 250tons, some versions even up to 500t) now use only automated gearbox

i think in future with high torque engines manual transmission will not be more offered

both scania and volvo offer automated gearbox with dry clutch up to 200ton

mercedes and zf wet clutch up to 250ton or even more

 

U sissy's need a 4x4 and a 2-speed rear, then come talk to me about syncro's LOL...... if you can't shift a crash-box transmission, then get back to your cubicle and answer the phones!

 

i tried it few time but all of those trucks are already extinct

it is 1984 man 19 361 with 12speed fuller , iveco was last manufacture which used crash box, mercedes used them on some models in late 60´s
my father had one of them and other one same truck but syncro both 12speed
in last 60 scania did not have crush, except they used to put eaton in australian market on some trucks by request in late 70´s ,80´s until 1991

but some things i usually do can not be made on this gearbox

i usually rock truck ( construction truck while i am in mud or to pass uneven

and on this truck i can be in reverse and go forward and after this just to release clutch and go reverse after this just press clutch or even worse case for fuller to shift in to reverse when i go forward and than shift in to 1st when i still go in to reverse

also going on really steep hills when you need under load change range group and more speed at same time for example from 5Th High gear to 3rd low

 

if your good, you can rock an eaton, been there done that..

my iveco is so heavy over the steer that it tends to dig in.......

and as for range changes and such, they are easy enough to do..

apples and oranges really. we can go around this all day long, fact is you've only played with syncro and amt, and many others have only had RR trans.

i think we can be glad for the fact that the old aux box style is gone.

after driving RR, syncro and amt i can say without a shadow of a doubt that i prefer RR.
Should i ever discover a need/desire for AMT then i would be wanting something equipped with a ZF AMT, as they are by and far away the best of the bunch.

 

When was I talking about AMT?

Here heavy haulers (250+ tonnes) use Allisons these days, they don't miss a gear.

Why arent Fullers lasting in our use, at 60 tons? (I could ask the same about Caterpillars)

 

Lenny i cant tell you why they dont last in eu. I do know thatcat were by far the most prefered for hh out here dragging roadtrains. Since they stopped supplying anything and everything is getting a run. Seems that most are still lamenting the loss. Ultra heavy is and always has been the doman of spicers. An allison is outside thr scope of this discussion so it is pointless to bring that up.

 

I think the original reason trucks in the US weren't given synchros is because of the added weight, cost, and additional complexity.