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a_boogs
22-01-11, 10:19 AM
Hey guys,

Long story short have put a D30 HP front axle in my ZJ and haven't got time to order and fit a front tailshaft before i get married...... SO does anyone know if you can run an NP 249 t'case without the front drive shaft in and still have the vehicle driveable in AWD mode??? also if this can be done is it going to damage the T'case in any way??? Only need to drive the car about 500kms then i will have time to sort out a shaft that is the right length.

Cheers again for any help guys

stevet
22-01-11, 10:37 AM
You can drive it without the front driveshaft attached. I ended up doing just over a 1000k's in mine by the time I had mine replaced but drove real easy when no front shaft in...........

Steve F
22-01-11, 11:12 AM
Doesn't the NP249 have a viscous coupling in the tcase, driving without the front shaft in for very long will probably kill it as it will be slipping a lot and build up a lot of heat :(

Cheers
Steve

Hunno
22-01-11, 03:19 PM
I drove mine home from the Blue Mountains back to Sydney with out the front drive shaft & ran so much more free that it got me looking for a 231 or 242 T'case. However Steve F is right, the NP249 does have a viscous coupling & will slip building a lot of heat.

Flatfender
22-01-11, 06:37 PM
I'm not familiar with the NP249 t'case but don't follow the reasoning here - if it has a viscous coupling will it not just drive the front output yoke anyway? What will make it slip?
Cheers
Ian W.

a_boogs
23-01-11, 10:56 AM
well as usual you guys were right... the jeep does drive quite well without the front drive shaft in... for the record i have found out that the reason for this is because the front wheels do not engage until the rear wheels begin to loose traction so the front output shaft doesn't even move while driving on the road...

cheers for the help lads

SteveC
23-01-11, 05:24 PM
I think the front shaft is always spinning as it's attached permanently to the front differential. It's at the transfer Box that it is either engaged or not. (I THINK)

a_boogs
24-01-11, 05:30 PM
what you say is true that it is always spinning, however as i do not have the front shaft in at the moment the output yoke will not spin till the rear wheels loose traction

Hunno
24-01-11, 06:51 PM
But how free does it drive without driving the front wheels.
Lookout if you go onto dirt roads again, in 2wd its like driving in the old days.