Fifth gear in Cat 428C

[Maxgas]

Hello folks

Just checked a used Cat 428C 2001 5000 hrs. today. Since I am new to this machine I was surprised to see that it has a Fifth gear in the powershift activated on a push button on the dash.
When the button is activated, it will automaticly kick in the 5. gear when you have build up speed in 4.th gear, and automaticly go back to 4.th when you loose speed.
When button is not activated, it will stay in 4. th gear.

Is this just a normal torque lock up?
Is it normal that you feel when its kicking in ? It feelt like an old style hi/lo. Not a big hump, just slightly

Any adwice will be helpfull
Thank you very much

Max Madsen

 

[PDG X]

Cat does not use locking torque converters on any of the pre-F Series machines. They usually have 2 forward clutch/solenoids with slightly different ratios to get the output speeds needed for each gear. You can get 5th gear for roading, but only under control of the machine based on speed and load. D's and later allow it in AutoShift mode. Earlier midels allow it in 4th if conditions call for it.

 

[Extractorfan]

Hi Max,
I have a 2012 CAT 434E with autoshift, and as you say 5th gear is only available with autoshift switched on,as PDG X says the gear shift is dependant on load & speed.
As the gearbox changes up or down you will feel it change gear but it is not a harsh shift. I tend to only have the autoshift switched to obtain 5th the other gears I change manually.
Hope this helps.
Ex tractor fan

 

[Maxgas]

Hi again

Thank you for the help.
I contacted a Cat technician about the question too, and he agree with you gyes. It is a 5. gear with a kind of lock in the transmission so that the converter does not slip going uphill when transporting. It is normal that you feel the 5. gear kick in since some clutches in there will never run in the exact speed when it kicks in.

Thank you.

Max