Dual range bogie drives

.
.OK....with all this talk about 2 speed diffs and dual range diffs ..............
Exactly what is the difference.........there has to be something ?????????
...............Billy................

OR is there nothing.??????...........

The 2-speed as in the Eaton uses epicyclic reduction gearing concentric with the crownwheel.
The double reduction as in Rockwell uses a sliding mesh gear set ahead of the differential.
If I remember right, Dodge used double a reduction diff back in the 60’s when other brands used Eaton’s.
The Eaton shift was much faster and more reliable, didn’t get hung up between shifts like the double reduction setup often did when changing on the move.

.
.I should have said i was referring to Eatons ........
as they were the ones that advertised the Dual Range set up.
and were a single reduction job ......

.................Billy...................

I think it's different terminology for the same thing, used in different applications. Two speed for a single drive and dual range when in bogie configuration.
Proved the power divider was not engaged, it should be able to cope with dual range changing out of sinc. I knew a fellow who had dual range diffs and he changed them, on the move as a matter of course.

BillyP wrote:

.
.OK....with all this talk about 2 speed diffs and dual range diffs ..............
Exactly what is the difference.........there has to be something ?????????
...............Billy................

OR is there nothing.??????...........

Good Question Billy..!!
I've seen inside My Share of Diffs over the Years including a couple of Number4 Eaton 2 Speeds. But am yet to go inside a Dual range one.. !

V8Ian wrote:

I think it's different terminology for the same thing, used in different applications. Two speed for a single drive and dual range when in bogie configuration.
Proved the power divider was not engaged, it should be able to cope with dual range changing out of sinc. I knew a fellow who had dual range diffs and he changed them, on the move as a matter of course.

.Ian the Great........You have nailed the situation greatly ...........Just terminology...........
Yep, just your every day Eaton 2 speed , set up for a bogie drive............
Can you change on the trot??? ........of corse you can....if you are that way inclined..........
However , remembering the old 5 speed boxes where you would split the change with the 2 speed diff to get
that in between gear , ..........
How would you manage that behind an 18 speeder when the step in the diff (may)??? equal a couple of
progressive shifts in the box...........bit of a lost cause i would think...........
So Mr Eaton may have said , we wont refer to the bogie set up as 2 speed (considering the HP and the
multi speed boxes ) ............ ,I know , lets call them a DUEL RANGE.............
So now there will be no splitting gears , just a lower ratio to get that heavy load rolling, then move to high range
when suitable to keep up the highway speed (or what ever )............
So there you go..........still just a 2 speed , capable of range changing on the trot if required ........
Remember if you walk out your front door the wrong way you could fall and break your neck ( or whatever )........
So if you dont do the diff change the correct way you could wring its neck just as easy .................
..................Billy....................

Good Question Billy..!!
I've seen inside My Share of Diffs over the Years including a couple of Number4 Eaton 2 Speeds. But am yet to go inside a Dual range one.. ![/quote]
.
Seed..........When you do open up that duel range, you will probably say
Hell, this looks just like an Eaton 2 speed bizzo ...................

...................Billy....................

I think the problem with shifting on the run comes when one diff changes and the other one is a bit slower, and doesn’t engage.

1976 we specd up a KW SAR for gross over 100t to get all the gearing they suggested RT-125015
there was no room to run a joey box as we wanted short W.B. so they suggested Dual range Eatons 44DT .. 4.56 -6.21 (95kph)
then they were hesn't on the deal as they had trouble with road trains changing the DR on the run
so we suggested to mount the switch out side the cab = problem solved
normally when we were well up in wieghts I'd put the diffs in low and do the loaded jouney in Low (max about 80kph)
I had problem one time under warranty where one diff changed and the other didn't (did change eventually after a few minutes of stuffin around)
Contacted KW they refered to Eaton
Eaton said we did not have enuff air up ..... we didn't allow nuff time to change the diff.... we had the parking brake on etc etc etc
then they said take it up with KW as they designed the DR plumbing
FFS
When I loaded the large crawler crane i left the V892T idiling with trailer maintaining air supply
parking maxi brakes applied on flat ground and low selected in the DR = 1/2 hour
as I took off with gentle applied power to the ground it was leaving a black tyre mark doun the road so stopped backed up 1 m tried again = same result
stopped put the DR in to hi moved forward 1m all ok then stopped again selected Lo in DR no problems from then on
I think to change from lo to hi or hi to lo on a DR U need to B cruising and allow the wheels to catch up with each other and not split gears like in a single drive 2 speed diff

WotSezU?



cya

BillyP wrote:

V8Ian wrote:

I think it's different terminology for the same thing, used in different applications. Two speed for a single drive and dual range when in bogie configuration.
Proved the power divider was not engaged, it should be able to cope with dual range changing out of sinc. I knew a fellow who had dual range diffs and he changed them, on the move as a matter of course.

.Ian the Great........You have nailed the situation greatly ...........Just terminology...........
Yep, just your every day Eaton 2 speed , set up for a bogie drive............
Can you change on the trot??? ........of corse you can....if you are that way inclined..........
However , remembering the old 5 speed boxes where you would split the change with the 2 speed diff to get
that in between gear , ..........
How would you manage that behind an 18 speeder when the step in the diff (may)??? equal a couple of
progressive shifts in the box...........bit of a lost cause i would think...........
So Mr Eaton may have said , we wont refer to the bogie set up as 2 speed (considering the HP and the
multi speed boxes ) ............ ,I know , lets call them a DUEL RANGE.............
So now there will be no splitting gears , just a lower ratio to get that heavy load rolling, then move to high range
when suitable to keep up the highway speed (or what ever )............
So there you go..........still just a 2 speed , capable of range changing on the trot if required ........
Remember if you walk out your front door the wrong way you could fall and break your neck ( or whatever )........
So if you dont do the diff change the correct way you could wring its neck just as easy .................
..................Billy....................

The fellow I knew, would either change in the gear he started in, or once he got into top. He had a 15 speed.