- Thread starter
- #21
Ok, so I have a center diff lock button, so I assume no viscous coupler is involved. How much time am I really spending in 4x4 with the center diff unlocked?
Marks 4WD Part Time 4WD adapter kit
- Thread starter Tim Collier
- Start date
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SmokingRocks
hopelessly addicted to Cruisers
OK think of your 4wd system like this:
0---FD---0.......Front Diff is OPEN
.......!
.......!
......CD...........Center Diff is OPEN
.......!
.......!
0---RD---0.......Rear Diff is OPEN
So power is applied to all wheels until one wheel slips then all the power goes to that wheel, this is how the system behaves if you DON"T have a VC. The VC is like a limited slip clutch, if a wheel at the front looses traction instead of all of the power going out through that wheel the VC uses fluid to 'couple' the rear drive shaft to the rotation of the front drive shaft. This coupling splits the power and sends some to the axle with traction automatically and seamlessly. The VC doesn't take the place of the center diff lock, it can only send something like 20 or 30% of the power to the other axle, the CDL 'locks' the split 50/50.
0---FD---0.......Front Diff is OPEN
.......!
.......!
......CD...........Center Diff is OPEN
.......!
.......!
0---RD---0.......Rear Diff is OPEN
So power is applied to all wheels until one wheel slips then all the power goes to that wheel, this is how the system behaves if you DON"T have a VC. The VC is like a limited slip clutch, if a wheel at the front looses traction instead of all of the power going out through that wheel the VC uses fluid to 'couple' the rear drive shaft to the rotation of the front drive shaft. This coupling splits the power and sends some to the axle with traction automatically and seamlessly. The VC doesn't take the place of the center diff lock, it can only send something like 20 or 30% of the power to the other axle, the CDL 'locks' the split 50/50.
- Thread starter
- #23
Ok, so on the average drive on pavement, how would you estimate the power split front vs rear? About 70% rear, 30% front?
SmokingRocks
hopelessly addicted to Cruisers
who knows, its pretty much 50/50 until there is slippage. In the event there is slippage the VC can only transfer 20 or 30% of the power to the axle with traction. I'm getting the feeling that you don't fully understand how an open differential works. Here is a video that explains it (it's old but very thorough:
The VC is a device that is added to the center differential to act kind of like a limited slip clutch.
The VC is a device that is added to the center differential to act kind of like a limited slip clutch.
- Thread starter
- #25
Right, got the axle differential. But, i bought a euro spec hdj80. I don’t think i have a VC in the center diff, have a factory center diff lock switch. (Would have loved to find a truck with F/R diff locks, but oh well). So, i am wondering how the driveline splits power front to rear from the center diff to the f ad r axles, and thus consider benefits or lack therefore a PT kit. Thanks for the dialogue, most helpful!
Just waking this thread up because it is a good read. AND...if anyone needs a Marks Part Time kit. I currently have them in stock...$650 Cash. Bearing pressed and ready.
Pm'd
