I have searched on this but can't find this specific info, and am now panicking.

I had an MOT last week and to be honest I think the tester was a bit clueless.

He insisted that the newage impreza WRX is differnt from the 'older' ones (mines a 2007 hawkeye) does not have traditional permanent 4x4 and will be fine on 2 wheel rollers. He tested the front and the backs separately on the rollers...

Now - I have been reading about LSD damage etc. and would like to get an idea of whether he is talkiing nonsense or not. Is it safe to test the brakes on a 2007 Hawkeye in this way (or in fact legal as per VOSA requirements)?

How likely is it that damage has been done and what's the best way to test for any damage?

Obviously the test was very short, just a few revolutions to test the footbrake and handbrake.

Fingers crossed...

Thanks

 

I always make sure my car doesn't go on the rollers , and a tapley meter is used with me driving , heard the rollers can wind up the centre diff or something , on my mot centres website it says all 4x4 should be tested on road with the tapley meter

 

+1

 

+ another

Also if you have had a problem with the MOT as a result of this you only have a finite time to dispute the test results.....from memory its 30 days I think but I could be wrong.

 

Had no issues and passed.

Thanks for the posts. Thought as much. Grrr.

They also adjusted the headlights so high they lit up the trees on my way from work - but I am currently taking them to task over that...

So - what's the likelihood of any damage being done on a low mileage car like this for the limited time it was in the rollers?

I know it's not ideal, but is it realy likely to have lunched the LSD?!

As several previous discusions have pointed out, surely handbrake turns, snow driving etc does something very similar?

 

If the rollers were only for 2 wheels then IT SHOULD NOT BE MOT'd on the rollers. Make it known to the garage that you saw them do it, and that they have tested the vehicle incorrectly which could cause damge to the rear diff, front diff or transmission. They know that it should be done with a tapley metre - it's in their basic training!

 

But on further searching this reassures me somewhat:

https://www.scoobynet.com/scoobynet-...rake-test.html

Sounds like a polarising discussion.

 

As an mot tester I check the brake performance on all permanent 4 wheel drive cars using tapley (decelerometer)

 

Wil be calling VOSA on Monday. Also to follow up on their headlight adjustment technique...

I took the car to another testing station today and they had to wind the headlights WAY down. They said thay had never seen lights set so high.

 

Go for it brucey. About time the white coat VOSA jobsworths had to actually work for their money.

 

Never put a 4wd on 2 wheel brake test machine...it's basic stuff and sound like the garage is way out of date or just ****

 

Mine never gets put on the rollers, I wouldn't be happy even if the risk is Low

 

All cars are mot'd in government run mot centres here in n.ireland and ALL only have 2 wheel brake testers but they have ones that specifically allow 4wd cars to be run basically one side will run in opposite direction to the wheel they are testing.

 

Ok so while testing lets say a front what are the rear wheels doing?

 

Nothing as there is no drive going through it hence the other wheel on front axle rotating in opposite direction

 

They put mine on the rollers couple months later the centre diff chewed itself apart over £1000 later on a rebuild.......

 

Plus spoke to vosa its a big no no. 2003 blobeye wrx btw

 

Sorry thats poppycock. Remembering lsd's etc etc rotating one wheel in the opposite direction make no difference. In fact with a lsd diff will probably maker things worse

 

Its in neutral.

There is 17 mot centres in NI, thats for all vehicles in NI, and all government run. If your 'poppycock' theory was correct do you not think there would be uproar across NI where any vehicle with awd was constantly getting fooked after every mot?

 

Not good...

Any come back on the garage when it happened to you?

What's your recommendation for my next steps??

 

Ring vosa and tell them, maybe say to them you want it inspected? Charge the garage? It got gradually worse but not immediately so wasn't in the 30 days, I know there was no other cause as I commute to work getting over 33mpg so it's not driven hard.

 

OK thanks - how many miles had your car done?

Thanks

 

I dont see what being in neutral has do do with it?

The diffs etc are still being turned by the wheels rotation. i.e the wheel is turned which rotates the driveshaft,diff,prop and centre diff.

I dont know what equipment is being used in N.I. It obviosly far better thsn anything we have on the mainland as its basic knowledge here that anything 4wd doesnt go on a 2wd brake roller tester.

 

More here:

https://www.scoobynet.com/929112-mot...r-drive-2.html

I'm still in a dilemma as my MoT is tomorrow and the garage only have 2WD rollers, but I'm reassured by Alan Jeffery's posts in the above link.

 

About 87k all was fine before no noise or anything.

 

I would insist on a tapley test from now on, they're pretty useless as my tester I use now said the handbrake would probably pass the normal brake test lol. You know if your brakes aren't up to scratch though!

 

As most of the posts above, permanent 4wd vehicles are excluded from the standard single axle brake test. My mate does mot's at his garage and Never puts my scoob on the rollers.

 

when the car is in neutral the transmission is disengaged effectively hence the prop shaft is not spinning. you can rotate a wheel on the axle without causing load on the centre diff aslong as the opposite wheel can also freely rotate in the opposite direction

only way i could possibly explain it is if you ever built/had 4wd tamiya remote control buggys as a kid you'd understand the principle more lol


watch at 1.30 where he rotates each axle without effecting the other axle. the same principals apply

 

I had the MoT done today on my Blob. The tester took one look and said 'that's permanent 4WD, we'll have to use the decelerometer, it can't go on the rollers'.

That's what I was hoping for, and it passed the MoT too.

 

Glad it passed. I'm an N.T. and youd never see an awd/4wd on our rollers