VR ABS rear brakes spin with brakes oushed on

[aussie4life]

I once braked so hard that i nearly overrode the abs. i could feel and hear the brakes lock for a split second and then the tyre squeel. even if i come into our property to hot and have to his the picks i can feel the brakes pulsating thru the pedal

 

[hako]

Mine pulses as well - I think series 2 VS had the newer/later style Bosch ABS pump so maybe there is a difference there.

 

[bucks418]

Wow, great responses. Thanks all. I am not sure if I explained properly in the initial query. It is not the pulsation that I am asking about. When I did the check on the brakes it was the same as a transmission stall test. Vehicle standing still, brakes full on. When I accelerate the rear wheel spin. I did this on my gravel driveway.

It seems some are saying this is normal for VR VS but nothing definate as it is clouded with the pulsation debate.

So should the wheels still spin under these conditions?

To add to the pulsation debate, I feel some pulsation, minor, but definitely not like the feel I get from my VT.

 

[Sabbath']

You're testing on a gravel driveway where there is little to no grip. Test it on a proper surface and then get back to us.

 

[Brett_jjj]

Wow, great responses. Thanks all. I am not sure if I explained properly in the initial query. It is not the pulsation that I am asking about. When I did the check on the brakes it was the same as a transmission stall test. Vehicle standing still, brakes full on. When I accelerate the rear wheel spin. I did this on my gravel driveway.

It seems some are saying this is normal for VR VS but nothing definate as it is clouded with the pulsation debate.

So should the wheels still spin under these conditions?

To add to the pulsation debate, I feel some pulsation, minor, but definitely not like the feel I get from my VT.

Even with ABS fitted, the rear wheels will always spin up if the brakes are held on and the engine accelerated whilst its in gear. As I mentioned in an above post, traction control is what controls or limits excessive wheelspin, not ABS.

 

[hako]

I'm not sure they should spin - I've done stall tests with my old Jag and the XF Falcon before that and never even had a hint of spin although I must admit it was on a concrete driveway.
Offhand I'd say there has to be some reason why the wheels are not locked solid...maybe pads are glazed or the hydraulic flexible hose or solid lines are partially blocked, but personally I'd want a bit of reassurance that it was OK. So I'll take an each-way bet.

 

[bucks418]

Thanks Sabbath. I'll have to try it next week. I am off to sydney for 5 days. I'll ask my son to try it while I'm gone.

You're testing on a gravel driveway where there is little to no grip. Test it on a proper surface and then get back to us.

 

[bucks418]

I'm not sure they should spin - I've done stall tests with my old Jag and the XF Falcon before that and never even had a hint of spin although I must admit it was on a concrete driveway.
Offhand I'd say there has to be some reason why the wheels are not locked solid...maybe pads are glazed or the hydraulic flexible hose or solid lines are partially blocked, but personally I'd want a bit of reassurance that it was OK. So I'll take an each-way bet.

Hako, I agree with that I've never had it happen before but I have always done them on concrete or bitumen. All the brake components seem fine.

 

[Brett_jjj]

Holding the brake on and flooring the accelerator will make the wheels spin, even if its on concrete/bitumen. Ive pulled plenty of big burnouts over the years like this.

 

[kingswood country]

I've always wondered why the abs doesn't pick up on the front wheels being locked when there is speed in the back wheels......

But yes it's normal, my vs does it in dirt and in the wet.

And a vs pedal does pulsate, it sounds like it's groaning and the pedal feels like it has vibrating through it, like a warped rotor almost.