Does a prop shaft count as a suspension component

[MaxRothery]

For those who know of my stupid questions, this one may be the most stupid.
And yes, this does seem like the wrong place to ask
Does a half shaft count as a suspension component in the DVLAs eyes?

Got a plan for AWD conversion and relying on it not counting as a modified suspension so I can modify the subframe which is considered the front axle

[Iva Barchetta]

Prop shaft..no

Half shaft.....no.

Both part of transmission.

[MaxRothery]

Iva Barchetta said:

Prop shaft..no

Half shaft.....no.

Both part of transmission.

Transmission? Thought it would be either axle or suspension

[Cat]

The DVSA Categorisation of Defects manual refers to prop/drive shafts as transmission components.

Cat

[Cooperman]

The prop shaft and drive shafts 'transmit' the power to the wheels, hence they are the 'transmission'.

[Variomatic]

It depends on the suspension layout, but generally the shaft isn't part of the suspension. Afaik there's no front suspension out there that uses the shaft, but some forms of rear suspension use the drive shaft as the lower link / arm.

The acid test is - if you removed the shaft and reassembled everything else, would the wheel stay where it's meant to be? If it would then the shaft isn't suspension. If it'd try to fall over or move about then it is.

[MaxRothery]

Variomatic said:

It depends on the suspension layout, but generally the shaft isn't part of the suspension. Afaik there's no front suspension out there that uses the shaft, but some forms of rear suspension use the drive shaft as the lower link / arm.

The acid test is - if you removed the shaft and reassembled everything else, would the wheel stay where it's meant to be? If it would then the shaft isn't suspension. If it'd try to fall over or move about then it is.

Would either replacing my front hubs with FWD ones or modifications to the current hubs be considered as altering the suspension?

[PanzerCommander]

MaxRothery said:

Would either replacing my front hubs with FWD ones or modifications to the current hubs be considered as altering the suspension?

The way I understand/interpret it is for example a conversion from leaf springs to coil springs would count as changing the suspension under the points rule. Or another way of looking at it even if the suspension components were non OEM as long as they are the same type and used the same pickup points as the factory setup it doesn't come under the points rule. Insurers have to be told of course.

If I were interpreting the rules I'd be looking at a hub change as modifying the axle.

[MaxRothery]

PanzerCommander said:

MaxRothery said:

Would either replacing my front hubs with FWD ones or modifications to the current hubs be considered as altering the suspension?

The way I understand/interpret it is for example a conversion from leaf springs to coil springs would count as changing the suspension under the points rule. Or another way of looking at it even if the suspension components were non OEM as long as they are the same type and used the same pickup points as the factory setup it doesn't come under the points rule. Insurers have to be told of course.

If I were interpreting the rules I'd be looking at a hub change as modifying the axle.

because the car id be converting came in both FWD and RWD, the hubs used can be OEM but the hubs are hard to find so would most likely modify the current hubs to accommodate the bearing carrier section from another car (most likely a RWD hub from an IRS car)

and if it is axle, then ill be modifying that anyway as the front sub frame counts as the axle which ill be drilling holes in

[GroundEffect]

MaxRothery said:

Iva Barchetta said:

Prop shaft..no

Half shaft.....no.

Both part of transmission.

Transmission? Thought it would be either axle or suspension

Transmission & Driveline.

Not part of chassis.

[Countdown]

MaxRothery said:

PanzerCommander said:

MaxRothery said:

Would either replacing my front hubs with FWD ones or modifications to the current hubs be considered as altering the suspension?

The way I understand/interpret it is for example a conversion from leaf springs to coil springs would count as changing the suspension under the points rule. Or another way of looking at it even if the suspension components were non OEM as long as they are the same type and used the same pickup points as the factory setup it doesn't come under the points rule. Insurers have to be told of course.

If I were interpreting the rules I'd be looking at a hub change as modifying the axle.

because the car id be converting came in both FWD and RWD, the hubs used can be OEM but the hubs are hard to find so would most likely modify the current hubs to accommodate the bearing carrier section from another car (most likely a RWD hub from an IRS car)

and if it is axle, then ill be modifying that anyway as the front sub frame counts as the axle which ill be drilling holes in

If we're talking about the hub that sits at the bottom of something like a macpherson strut then I would say that IS modifying the suspension. However the hub doesn't have anything to do with propshafts/driveshafts other than the fact that they slot into the hub.

[PanzerCommander]

Countdown said:

If we're talking about the hub that sits at the bottom of something like a macpherson strut then I would say that IS modifying the suspension. However the hub doesn't have anything to do with propshafts/driveshafts other than the fact that they slot into the hub.

I don't know tbh, this is where the regulations fall down because its open to interpretation. As I said above the way I interpret it is if the suspension type has changed, leaf springs to coils. Macpherson strut to double wishbone etc. then the suspension has been changed, the pick up points will be different, the springs and dampers will have different pick up points etc.

If the suspension was Macpherson strut before the new hub was installed and remains Macpherson strut after the new hub was installed has it actually been changed?

Converting 2WD into AWD then you are changing the transmission and axles and possibly the steering rack not the suspension but that is my interpretation of the rules.

[Countdown]

PanzerCommander said:

<snip>

If the suspension was Macpherson strut before the new hub was installed and remains Macpherson strut after the new hub was installed has it actually been changed?<snip>

I may be being way too simplistic here but

the hub is part of the suspension leg
it's been changed for a different type of hub
ergo the suspension has changed

No?

[MaxRothery]

Countdown said:

PanzerCommander said:

<snip>

If the suspension was Macpherson strut before the new hub was installed and remains Macpherson strut after the new hub was installed has it actually been changed?<snip>

I may be being way too simplistic here but

the hub is part of the suspension leg
it's been changed for a different type of hub
ergo the suspension has changed

No?

the suspension id double wishbone and will be staying double wishbone, id just be changing/modifying the hub.

and I wouldn't be changing the steering rack, the only thing keeping this road legal is the steering rack and suspension as axls will be swapped and modified to suit

[PanzerCommander]

Countdown said:

I may be being way too simplistic here but

the hub is part of the suspension leg
it's been changed for a different type of hub
ergo the suspension has changed

No?

I don't know, I'm just interpreting rules which are imho woolly. As I said if you asked me to list the suspension components on my own car I wouldn't even think about mentioning the wheel hubs.

[MaxRothery]

PanzerCommander said:

Countdown said:

I may be being way too simplistic here but

the hub is part of the suspension leg
it's been changed for a different type of hub
ergo the suspension has changed

No?

I don't know, I'm just interpreting rules which are imho woolly. As I said if you asked me to list the suspension components on my own car I wouldn't even think about mentioning the wheel hubs.

I think it would count as its what the suspension components connect to, therefore modifying the half shaft to fit the hub would be the way to go. also, rather than converting the RWD version to AWD, converting the FWD to AWD as the suspension is the same, but its just a tubular axle rather than a live axle.

[fatboy b]

Iva Barchetta said:

Prop shaft..no

Half shaft.....no.

Both part of transmission.

Unless you have an old Jag. Then the half-shafts are part of the suspension too.

[MaxRothery]

So, is the wheel hubs part of the suspension?

[dlockhart]

from the definition above the wheel bolts are part of the suspension

[MaxRothery]

dlockhart said:

from the definition above the wheel bolts are part of the suspension

Cheers