Page 1 of 1

Landcruiser 1990 80 Series "All Wheel Drive" ? ? ?

Posted: Thu Nov 15, 2007 10:31 am
by 80landcruiser
Could you assist me with a problem which I may or may not have. After having both drive shafts off (Front and rear) I installed the rear one first. I started the engine and wanted to see how it drove with only the rear shaft, however, after engaging first gear the car would not move.

After scratching my head, I tried again, this time I got a mate to engage first gear and began accelerating, once again the car would not move, I then had a look underneath the car whilst he accelerated and notice that only the front flange of the transfer case was spinning.

I then press the diff lock button, and the car does go, which means that there is now power to the rear (still without the front drive shaft). I also, engaged the low range gear, and once again the car moved, also meaning that there is power to the rear (also without the front shaft)

I then connected the front drive shaft and the car drove perfectly, however, considering the Landcruiser is an "All Wheel Drive" vehicle, only the front wheels has power, making it a "front wheel drive"

Is this a problem that not all wheels has power or is this normal until the diff lock and low range gear is engaged?

The reason Im asking you is that I was under the impression that an "All wheel drive" means that all wheels have power, or is this a play on words?

Thank you in advance

Posted: Thu Nov 15, 2007 10:52 am
by me3@neuralfibre.com
There is a differential in the transfer case in the middle of the car. Diff's transfer power to the wheel with the least traction, in this case the disconnected driveshaft gave the effect of "no traction", and all the power went there.

Locking the centre diff (the button in the car) stops the power being split and locks the front and rear driveshafts together. Low range also locks the centre diff in automatically - there is a light on the dash to show when it's engaged.

If you run both tailshafts installed with the centre diff locked then front and rear are locked together. This is fine on slippery surfaces, but on dry bitchumen will have negtive consequences.

All Wheel Drive should actually be called "Any Wheel Drive".

Paul

Posted: Thu Nov 15, 2007 2:50 pm
by vSAHARAx
me3@neuralfibre.com wrote:There is a differential in the transfer case in the middle of the car. Diff's transfer power to the wheel with the least traction, in this case the disconnected driveshaft gave the effect of "no traction", and all the power went there.

Locking the centre diff (the button in the car) stops the power being split and locks the front and rear driveshafts together. Low range also locks the centre diff in automatically - there is a light on the dash to show when it's engaged.

If you run both tailshafts installed with the centre diff locked then front and rear are locked together. This is fine on slippery surfaces, but on dry bitchumen will have negtive consequences.

All Wheel Drive should actually be called "Any Wheel Drive".

Paul
Spot On!

Posted: Mon Nov 19, 2007 11:05 am
by 80landcruiser
Paul

Thank you so much for this information, you made it a lot clearer to understand what my percieved "problem" was.

Thanks once again.

Sherif