AWD testing - apart from prop test?

[robsterpaterson]

Hi folks. Apart from trying to turn the propshaft, are there other ways of checking that the AWD is working? I think that this morning proved mine is! Exiting a greasy roundabout, I felt the front slide a wee bit while 'on the power' just as I eased off the throttle and lessened the steering lock, it seemed to transfer some power to the rear because then the rear broke away slightly. Woohoo, drifting an XC!
I don't think I was pushing hard enough for it be lift-off oversteer so I'm quite content that the back end kicks in when required. However I'm curious to know of any other tests like maybe raising all four wheels off the ground and turning the fronts??

[gmonag]

Drive on loose gravel or mud and floor it whilst watching the rear wheels!

[gmonag]

There is an official method:

Test driving Active on Demand Coupling, automatic gearbox

Warning! Ensure that the car is safely raised. Check that no objects are caught in the tyre treads.

Caution! Carry out the test with the car raised so that all four wheels can rotate freely with the mounting at the ends of the control arms to prevent damage to the drive shafts.

Note! If the car has STC or DSTC, these functions must be disengaged. Press in the STC/DSTC button on the centre console. Hold the button in for at least 2 seconds. The LED on the button must go out.
If the car is equipped with TRACS (traction control system) the function must be deactivated. This is carried out by removing the fuse for the ABS modulator in the engine compartment fusebox. Note that diagnostic trouble codes (DTCs) will be stored in the brake control module (BCM). These must be erased before returning the car to the customer. For further information about the integrated relay/fusebox, see the Wiring Diagram.

-Ignition off
-Raise the car so that all the wheels are clear of the ground
-Depress the brake pedal
-Move the gear selector to position P
-Start the engine and release the handbrake
-Move the gear selector to position D
-Release the brake pedal when the car is idling. At least one wheel on each axle must rotate
-Depress the accelerator pedal (AP) and maintain a speed of approximately 60-80 km/h. All wheels rotate at the same speed
-Release the accelerator pedal (AP)
-Select N immediately after releasing the accelerator pedal (AP)
-Apply the handbrake when the wheels are still rotating at 60-80 km/h. Check that the rear wheels stop abruptly and that the front wheels continue to rotate
-Release the handbrake and depress the brake pedal. All wheels must stop
-Move the gear selector to position D
-Release the brake pedal. Check that at least one wheel on each axle rotates
-Depress the brake pedal
-Move the gear selector to position P
-Start the engine with the handbrake applied. The indicator lamp in the driver information module (DIM) must light - signal to the differential electronic module (DEM)
-Move the gear selector to position D
-Release the brake pedal when the car is idling. Check that the front wheels rotate slowly and the rear wheels do not rotate.

[Tannaton]

^^^^^^^^^^^ That should be a sticky.....

[AB-UK]

Agree - it should.

[cpu_man]

OR

once a year (when you get your mot done) ask the tester to drop the front wheels in the rollers, try to drive out, after around 2 secs of the front wheels spinning the back should push the front out.

easy.

[robsterpaterson]

Originally Posted by cpu_man

OR

once a year (when you get your mot done) ask the tester to drop the front wheels in the rollers, try to drive out, after around 2 secs of the front wheels spinning the back should push the front out.

easy.

Hmm, I have a friendly tester so I could try! gmonag's procedure does sound more fun though

[Bonefishblues]

When our XC70's splines went just a week or two after we got it, it instantly felt wrong, and aggressively fwd, iyswim.

[cpu_man]

Originally Posted by robsterpaterson

Hmm, I have a friendly tester so I could try! gmonag's procedure does sound more fun though

That's what I do and it works fantastic.

Front wheels should spin for a few seconds then the back will kick in and drag you out of the rollers, good way as well to wake up the rear drive system if never used.

[robsterpaterson]

So I got around to visiti9my friendly MOT guy today. We left his brake rollers switched off and drove the front wheels onto them. We stuck her in reverse and the rollers gave maybe quarter of a turn before the rear wheels dragged her off the rollers.
Sorted, AWD seems to be fine. However, I used to own a Golf Rallye from 1989 and it had Haldex. The only time that it was in permanent 4WD was when it was in reverse so I'm wondering if the Volvos are the same???
Just curious as the MOT said that felt like it was in 4WD when he was manoeuvring it forwards at full lock. I thought maybe full lock presents enough of a speed differential on the front wheels to make her think that a front is spinning and to transfer some torque to the rear?