4High? What actually happens?
#1
02-01-2009, 07:49 AM
4High? What actually happens?
Can someone explain what actually happens when we push those 4HIGH LOCK buttons on the dash? We're in 4WD all the time, correct? Does it lock the rear differential, and if so, how does that help?
#2
02-01-2009, 08:32 AM
H3s are full time AWD. The Transfer Case distrubutes power between the front and rear axle at 40% front, 60% rear.
When you select 4Hi Lock, the T Case locks the front and rear axles together and the power is then split evenly 50% like any other 4WD. The rear differential is not controled by Hi lock/Lo Lock.
Hi Lock is used to get more power to the front wheels and share the front traction to pull the truck through mud/sand/snow. The front is now helping the rear at the same amount moving the truck through obsticals requiring additional traction.
The rear differential with the off road adventure package can be locked left to right to evenly split the power to the rear and cause both rear wheels to turn in unison like a tractor. 2009s have an available front locking differential that will lock the front left to right and do the same thing in the front having all four wheels locked together and doing work spreading traction at all corners... the ultimate set up for max traction.
When you select 4Hi Lock, the T Case locks the front and rear axles together and the power is then split evenly 50% like any other 4WD. The rear differential is not controled by Hi lock/Lo Lock.
Hi Lock is used to get more power to the front wheels and share the front traction to pull the truck through mud/sand/snow. The front is now helping the rear at the same amount moving the truck through obsticals requiring additional traction.
The rear differential with the off road adventure package can be locked left to right to evenly split the power to the rear and cause both rear wheels to turn in unison like a tractor. 2009s have an available front locking differential that will lock the front left to right and do the same thing in the front having all four wheels locked together and doing work spreading traction at all corners... the ultimate set up for max traction.
#6
02-01-2009, 06:34 PM
H3s are full time AWD. The Transfer Case distrubutes power between the front and rear axle at 40% front, 60% rear.
When you select 4Hi Lock, the T Case locks the front and rear axles together and the power is then split evenly 50% like any other 4WD. The rear differential is not controled by Hi lock/Lo Lock.
Hi Lock is used to get more power to the front wheels and share the front traction to pull the truck through mud/sand/snow. The front is now helping the rear at the same amount moving the truck through obsticals requiring additional traction.
The rear differential with the off road adventure package can be locked left to right to evenly split the power to the rear and cause both rear wheels to turn in unison like a tractor. 2009s have an available front locking differential that will lock the front left to right and do the same thing in the front having all four wheels locked together and doing work spreading traction at all corners... the ultimate set up for max traction.
When you select 4Hi Lock, the T Case locks the front and rear axles together and the power is then split evenly 50% like any other 4WD. The rear differential is not controled by Hi lock/Lo Lock.
Hi Lock is used to get more power to the front wheels and share the front traction to pull the truck through mud/sand/snow. The front is now helping the rear at the same amount moving the truck through obsticals requiring additional traction.
The rear differential with the off road adventure package can be locked left to right to evenly split the power to the rear and cause both rear wheels to turn in unison like a tractor. 2009s have an available front locking differential that will lock the front left to right and do the same thing in the front having all four wheels locked together and doing work spreading traction at all corners... the ultimate set up for max traction.
WOW...ExAcTlY what I was gonna SAY!!!
#8
02-02-2009, 07:42 PM
I still don't understand what it means to have 40% front 60% rear. The engine is turning both front and rear wheels at the same speed - what, exactly, does it mean to distrubute power differently? It's just not intuitive.
#9
02-03-2009, 11:38 AM
50-50% is the standard Full Time 4WD.
A different distribution is like the AWD cars, many of them spread power to the front and rear in different amounts through their center differential. This allows different wheels to rotate at different speeds when cornering on dry pavement.
The H3 Transfer Case is a center differential of sorts, acts like and AWD for on road, and can be locked to go off road like a 4X4. Think of the T Case as a series of clutches and gears, not just Hi and Lo, but also lock and AWD.
Personally, I would rather have like a regular truck, 2WD for on road, and 4X4 for getting off the pavement. I do not need the AWD, just sucks up gas on pavement.
A different distribution is like the AWD cars, many of them spread power to the front and rear in different amounts through their center differential. This allows different wheels to rotate at different speeds when cornering on dry pavement.
The H3 Transfer Case is a center differential of sorts, acts like and AWD for on road, and can be locked to go off road like a 4X4. Think of the T Case as a series of clutches and gears, not just Hi and Lo, but also lock and AWD.
Personally, I would rather have like a regular truck, 2WD for on road, and 4X4 for getting off the pavement. I do not need the AWD, just sucks up gas on pavement.
#10
02-03-2009, 12:35 PM
There is more to it than that. 4Hi allows the transfer case to act as a differential between the front and rear wheels. Turning corners, and the tires not having the exact same circumference requires that they are able to rotate independantly to each other (because they are covering different distances) on hard pavement or they bind up the driveline, which causes chatter and squeal as they slip on the ground. It's rough on the entire driveline because of the binding. That is why it's VERY important to not use 4HI Lock or 4LO Lock on dry pavement. Now once the 4HI Lock or 4LO Lock switches are used the transfer case locks the front and rear wheels together so they rotate at exactly the same speed. Low traction surfaces like sand, snow, rocks, allow the wheels to slip the driveline is no longer bound up and you don't feel the chatter.
This same principle applies to the locking diffs. If you have a 2009 with front and rear lockers once in 4LO lock with the front and rear diff locks engaged ALL 4 WHEELS ROTATE at the same speed. That is why it's so hard to steer in this mode. DON"T wreck your driveline. Never, Never use the 4 HI Lock or 4 LO Lock on hard pavement.
That chattering is bad. Your truck is saying "don't do this to me"!
This same principle applies to the locking diffs. If you have a 2009 with front and rear lockers once in 4LO lock with the front and rear diff locks engaged ALL 4 WHEELS ROTATE at the same speed. That is why it's so hard to steer in this mode. DON"T wreck your driveline. Never, Never use the 4 HI Lock or 4 LO Lock on hard pavement.
That chattering is bad. Your truck is saying "don't do this to me"!