GVM Upgrade

Submitted: Sunday, Mar 06, 2011 at 22:07
ThreadID: 84840 Views:2068 Replies:3 FollowUps:2
This Thread has been Archived
Does anyone know how and what calculations they use to get the GVM upgrade fiqures? I was told add the front axle load weight rating and the rear axle load rating together. ?????
Back Expand Un-Read 0 Moderator

Reply By: Member - bungarra (WA) - Sunday, Mar 06, 2011 at 23:27

Sunday, Mar 06, 2011 at 23:27
All I know is that it appears to involve a litle more than that and I base that comment on the following experience

I have recently had a GVM upgrade to 3900 on my 'Cruiser 79 series. When I enquired around looking for a GVM upgrade there were those that were 3700 and another 3800

and so I assume it also involves the quality and engineering of the componets used in the upgrade to get the variations I mentioned above

I guess someone more knowledgeble will post on this subject soon

Life is a journey, it is not how we fall down, it is how we get up.
VKS 1341

My Profile  My Position  Send Message

AnswerID: 447525

Reply By: Dust-Devil - Sunday, Mar 06, 2011 at 23:28

Sunday, Mar 06, 2011 at 23:28
John P

There is a whole bunch of stuff that is taken into account re computing GVM'S.

In October 2005 I had the GVM of my 1997 75 series Troopy re-engineered from 3100kgs to 3495kgs.

The engineering certificate shows:

Original Specs 1400kgs front axle, 2000kgs rear axle - GCVM 6350kgs
Re-eng'd Specs. 1400kgs front axle, 2500kgs rear axle - GCVM 6350kgs

The maximum a 75 series Toyota GVM can be upgraded to is 3500kgs before you have to add a ridiculous amount of emission control gear, plus arduous testing programme, that makes it totally cost prohibitive to do so. The Engineer said at the time that it would be cheaper to buy two new Troopys.

With this in mind he took the upgrade to 3495kgs so that it was just under the magical 3500kg mark so that there would be no arguments.

You will notice that the GCVM did not change during the aforementioned exercise, and the GVM only increased to that allowable under then current regulations for my vehicle, not that by adding the axles together.

However what did also change was the Tyre Placard which increased tyre size specs a tad.

Engineering computations - The Engineer had a book the size of the old Encyclopaedia Britannica, which had all the engineering specs for the original vehicle build ( Brakes, springs, shackles, Shockers, wheels, tyres, axles, chassis etc etc) which were entered into a computer program along with all his vehicle test results, and bingo there you have it.

AnswerID: 447526

Follow Up By: Ozhumvee - Monday, Mar 07, 2011 at 08:03

Monday, Mar 07, 2011 at 08:03
The ultimate limit is the combined capacity of the axles but as DD shows if done correctly other criteria come into it which may result in a lower limit.
It always amazes me that people expect to be able carry far more weight in a vehicle than the manufacturer who designed it and spent millions doing so and decided on the original figures expects it to. The more weight you carry the faster components wear out.
Remember also that few manufacturers expect you to want to carry or tow at the stated limits for more than a certain percentage of the time so operating the vehicle at its maximum carrying capacity will lead to a shortened life.
I suspect that many have the wrong vehicle for their situation and should be looking at small trucks to tow and carry their loads.
FollowupID: 719824

Follow Up By: Member - Phil G (SA) - Tuesday, Mar 08, 2011 at 09:47

Tuesday, Mar 08, 2011 at 09:47
In which State did you get the engineering done?
I haven't heard of a 3,500kg limit before. In most States, the expensive rego and increased inspections come in at 4,500kgs.

And I'm amazed an Engineer can override Toyota's specs and upgrade the rear axle load by 500kgs!

FollowupID: 719962

Reply By: Snoopyone - Monday, Mar 07, 2011 at 14:29

Monday, Mar 07, 2011 at 14:29
Read your other thread for a reply this morning regarding this.

AnswerID: 447573

Sponsored Links

Popular Products (11)