2H to 4H While driving...Is it really possible?

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ra_01
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Re: 2H to 4H While driving...Is it really possible?

Post by ra_01 »

Yes I’ve seen that video when I was doing my research before I purchased my first Patrol. He didn’t mention anything about locking the hub if you want to switch to 4H while doing 80km/h. May be it’s an assumption that hubs must be locked!
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Re: 2H to 4H While driving...Is it really possible?

Post by iandvl »

The owners manual also says nothing about locking the hubs. However, when I first tried to shift from 2H to 4H with hubs on auto, one could hear the grating of the splines. Also, the shifting was difficult (as you also have noticed). Further reading on the matter indicated (to me at least) that shifting without the hubs locked could cause issues. Since there is really no difference in driving the vehicle in 2H with the front hubs locked, I prefer not to take chances, and I lock my hubs on the occasions where it seems as if I may need to shift between the two on the move.

ra_01
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Re: 2H to 4H While driving...Is it really possible?

Post by ra_01 »

Ian, I’ve also noticed this in my recent trip. Tried shifting to 4H while driving when the hubs are on auto and I could hear a noise..so didn’t take any chances.

It’s funny the manual also didn’t mention anything about locking the hub.
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Re: 2H to 4H While driving...Is it really possible?

Post by ra_01 »

Saw the video again. If hubs are locked then we could shift to 4H at upto 80km/h, and 40 km/h when on auto.
But that’s on manual gearbox.

https://youtu.be/n6wt6d_xvrA
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Re: 2H to 4H While driving...Is it really possible?

Post by Jacor »

A slight variation to the posted question.

I have a Lock-rite auto front locker. Can I still drive in 2h with the hubs locked and shift to 4h when needed?

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Re: 2H to 4H While driving...Is it really possible?

Post by Reenen »

Jacor wrote:A slight variation to the posted question.

I have a Lock-rite auto front locker. Can I still drive in 2h with the hubs locked and shift to 4h when needed?

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Die locker sal geen verskil maak nie

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Re: 2H to 4H While driving...Is it really possible?

Post by Jacor »

Dankie Reenen.

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Re: 2H to 4H While driving...Is it really possible?

Post by davidvdm »

It's all about having the front and rear propshaft speeds matched inside the TC. Auto hubs will not have this happening as it disengages the front drive train. Manual Hubs, or Auto hubs set to the locked position will keep the front drievtrain engaged, and the propshafts spinning. My Sani TC can do it, and the Sani now with the Safari TC does it with hubs locked.

And it can be done virtually at any speed. I have noticed on a gravel road, at any speed while a having a fair amount of throttle applied, going from 2H to 4H does not want to go. The rear wheels are actually spinning on the roar surface compared to the front wheels that are just being pushed along. The Sani TC would offer resistance, but not make any noises. The Safari TC actually makes a bit a noise as it tries to engage the splines that are not running matched speeds. Get off the loud pedal and just coast, and the TC will go into 4H. Both the Sani TC and the Safari TC have done this at speeds of over 120km/h.

I drive permanently with the Hubs locked, as I am only on tar roads for about 40km every two weeks. I shift between 2H and 4H a few times a day. The TC will even have a problem shifting to 4H if you are executing a turn, as the front drivetrain will be covering a longer distance compared to the rear, causing mismatched speed of propshaft in the TC. I see guys here with auto Hubs have the same problem over and over, where they have to stop to engage 4H. Fairly irritating for us that have the capability of doing this on the fly.

One guy even does a reverse back and forward to engage and disengage. Frighting experience when are you able to just drop back to 2H on the fly and ready to boot the thing, and this guy stops dead, and reverses back at you a few meters before he can carry on.
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