GCM upgrade

Tony, reading VB6 it refers to Heavy Vehicles only.....

Oh thank god for that.

Paragraph 10 refers specifically to "LIGHT" vehicles. so the applicability of that para is for the tugs we use!

The relevant paragraph is
10. ARRANGEMENTS FOR SSM LIGHT VEHICLES THAT HAVE BEEN SUBJECT TO A GROSS VEHICLE MASS (GVM) UPGRADE
10.1 Where a light vehicle is fitted with or is required to be fitted with Electronic Stability Control (ESC) system and a full volume SSM IPA is being sought, a GVM upgrade SSM IPA holder will be permitted to use ESC test reports owned by other GVM upgrade SSM IPA holders for the same make and model, provided the test covers the variants to be supplied. Coverage of variants is to be demonstrated using a ‘worst case’ assessment and selection of fleet forms. Use of any test report must also be permitted by the test report owner.
10.2 Low volume GVM upgrades on vehicles with suspension lifts less than or equal to 50mm will not require testing of the ESC system. For suspension lifts exceeding 50mm, full ESC testing will be required.
10.3 For SSM IPAs issued under the low volume scheme, numbers per Licensee for GVM upgrade are capped at 300 vehicles per annum per vehicle category and 100 vehicles per annum per SSM IPA.
10.4 0-4-5 certificate submissions will not be required on low volume GVM upgrades where GVM upgrade is the only modification being undertaken under an SSM IPA.
10.5 Existing full volume SSM IPA holders have the choice of converting their full volume SSM IPAs to low volume SSM IPAs. No application processing fees will apply to these SSM IPA conversions.
10.6 The towing capacity of a light vehicle expressed as Gross Combination Mass (GCM) rating or Rated Towing Capacity or Maximum Braked Towing Mass rating must not exceed the value set by the first stage manufacturer. Second stage manufacturers are not permitted to increase the towing capacity as part of an SSM IPA that results in GVM upgrade.

Johnat, VB6 is what I was replying about and it does not have anything to do with GVM or GCM upgrades, only bullbars.

That's correct, Tony.

No more upgraded Towing Capacity.

Upgraded GVM, and therefore upgraded GCM, is still OK.

Tony, correct it doesn't affect the gvm as that can be lifted by a secondary manufacturer. You can't upgrade the gcm or gross combined mass and the only way it can be done is if the primary manufacturer agrees to it and I wouldn't think they would be jumping into that.

The "carrying capacity" of the vehicle is GVM, not GCM. As I read it, you can still get an upgrade to GVM but not to GCM or to braked towing capacity.

Yep, I think this is fairly clear:

10.6 The towing capacity of a light vehicle expressed as Gross Combination Mass (GCM) rating or Rated Towing Capacity or Maximum Braked Towing Mass rating must not exceed the value set by the first stage manufacturer.

Second stage manufacturers are not permitted to increase the towing capacity as part of an SSM IPA that results in GVM upgrade.

So you can carry more in you tow vehicle but it will subtract that amount from the towing capacity.

Chris, I would be getting ruling on that from the horses mouth to be on the safe side

You can only go by what is stated.

Para 2.1 states it only applies to new vehicles, the paragraph says,

"2.1 SSM arrangements only apply to New Vehicles as defined in the Motor Vehicle Standards Act
1989, and do not apply to vehicles that have already been used in transport."
Chris

I agree with Frank. The GCM on my D-Max is 7100 kilograms. If I was that weight I would hate to have to stop in a hurry, because it would not happen. My normal travelling weight is about 3300 kilograms and the brakes are barely adequate to stop that weight let alone more than twice that weight.
Chris

Frank/Chris, I couldn't agree more. Nowhere is there even a breath of suggestion that brakes need upgrading with any increase in either GVM or GCM. It relies on them being "more than adequate" for the vehicle as delivered, which is generally an unsafe assumption.

I participate in a (manufacturer name withheld) forum where most members want to increase the engine power. Notwithstanding that the stock brakes are at least adequate, one of the first things they do is improve the braking capacity to keep abreast of the kW.

The vehicle being towed (caravan, trailer, whatever) should have its own brakes and should not impose much, if any, extra braking on the tow vehicle! I have my caravan brakes set so that I can feel them pulling up my car as I apply them. Maybe a little harder with override brakes, however the tow vehicle should never be taking the full brunt of the braking.

cheers Tony

Tony,

While braking has been mentioned, there is a lot more to it than that. (FWIW I have mine set similarly to yours - a slight lead to vehicle braking but not so much that they will lock up.)

Consider the strength, suitability and durability of the driveline, dynamic stability, erosion of manufacturer's safety margins, etc.

To be honest, I doubt that anyone can be sure that the bureaucrats who wrote the current GVM upgrade rules intended them to be used the way they are - ie to also increase GCM and braked towing capacity.

Whether they did or not, the system has decided it's not the way to go, and that's probably a good thing, IMO.

Cheers