S3 Haldex Quattro and MOT Rolling Road Brake Test

[s3facelift09]

I just spoke with a friend mechanic that works at the Audi Dealers workshop, and he heard from a friend that on some BMW with xDrive, when they were doing the MOT Rolling Road brake test, that the MOT centre wrecked the guys gearbox, and the damage was around 7k £

And I'm due with my MOT tomorrow, this isn't the first one, but I never thought about this matter. The problem is that when the brake test is being done on the front axle, the front wheels are turning on the rollers and the back wheels are on the ground (stopped), and I don't know could this be dangerous for the gearbox or haldex?

And is there a special Rolling road for 4x4 vehicles?

 

[Tezgreig]

I know when my car goes for a Mot they do Not carry out the brake test. Yes there are also 4wd rolling roads. A quick look on YouTube for 4wd rolling roads brings up loads of videos. Hth

 

[s3facelift09]

Could it be that the previous 5 brake tests have done some damage to the gearbox or haldex?

 

[Rob C]

I have a friend who is a mechanic and any 4x4 is road tested as opposed to doing the brake test in the rollers as I guess the above happens.

 

[Lewis583]

All BMW Xdrives aside from very early X5/X3 can be tested on the roller brake tester. I know this because I test them pretty much everyday. With the BMW system the 4 wheel drive is only engaged when the throttle pedal is touched.

As for the quattro haldex system, when I MOT'd my old A3 I always carried out the brake test with the decelerometer because I didn't know how the system would react to being put in the rollers. I wasn't about to try it on my own car haha.

 

[-Ju-]

I had mine tested midweek and they just skipped the brake test saying its 4wd it'll be fine

 

[Marshy]

Tested loads of Quattros on a rolling brake test.
The decelerometer is for cars that are permanent 4wd.
Never heard of any issues with the electronic switched 4wds as they're 2wd until electronically engaged.
As above I'm sure they look for a road speed or gear selection and accelerator input.

 

[s3facelift09]

Tested loads of Quattros on a rolling brake test.
The decelerometer is for cars that are permanent 4wd.
Never heard of any issues with the electronic switched 4wds as they're 2wd until electronically engaged.
As above I'm sure they look for a road speed or gear selection and accelerator input.

You've tested loads of haldex quattro's? You drive an S3/RS3, did you test your car also? I guess you didn't encounter a problem?

 

[Marshy]

I tested my last S3 no problems .
Also done Skoda yeti's with haldex, I've never had a problem or heard of anyone having problems.

 

[Carterleeds]

About 5 different garages in Leeds always do a 4x4 quattro brake test on the road never on the rollers.

So I personally would be cautious if done on 2 wheel drive rollers.

I always assumed anyways that on all quattros or 4x4 when the front wheels move the back wheels move due to it being all connected mechanically....

 

[Tezgreig]

I can see what Marshy is saying with it being 4wd electronically activated out of gear won't be a problem on brake rollers. But hen how many mot garages understand how Haldex works probably being cautious on there part ain't cheap if they break it

 

[Conza]

At work we have a special unit u stick on the passenger seat and go up the road and do brake test while driving normally