GVM upgrade

[prelude]

Hi all,

I know I do not live down under so the rules are different over there. :)

So, I have been adding a lot of gear to my P38 and if you have followed the other threads on here you may have noticed that I have gotten closer and closer to GVM just by adding bars, winches, bash plates and the likes. I reckon that with the rtt, fridge, spare and a full tank of fuel I would have no carrying capacity left for any supplies, recovery gear (heavy) etc.

Now, I know the rear axle at least is pretty much the same as in a defender (puma)? or is that just the diff? In any case the defender has a much higher carrying capacity and if I look at the plate in the front the rear axle should be capable of carrying more weight.

In other words; do or have gvm upgrades exist(ed) for the P38? The local DMV is extremely inflexible in adjusting anything so even if I were to go that route I would have to temporarily export my vehicle to a neighbouring country that is a lot more accommodating and then re-import the car. Why? Well the rules say the our DMV has to accept ANY vehicle that has been accepted by another EU state [bigwhistle]

Before I even consider going through all that hassle though I would be nice to know if anyone has already invented this wheel which could make my life a whole lot easier!

Thanks!
-P

[MaestroMan]

If you're running coil springs, realistically all you really need to do is increase the spring rate to improve the GVM. The ladder frame is already pretty stiff, and the axles, as you mentioned, are the same basic design as a Defender. Old Man Emu makes what you need, most likely. The transmission, engine, and final drive gears are unlikely to complain about some extra payload given that the trailer towing maximum is already 3500kg.

If you're running air springs, I doubt there's much you can do to improve the load capacity. The rubber has a max operating pressure of 100psi. I don't think the Arnott Gen 3s are designed for higher loads than stock.

As for miscellaneous other stuff, I'd recommend upgrading your brake pads to ones meant for trucks/towing and getting a set of LT-rated tires if you didn't already have them. You'll want to run significantly higher pressure than stock (probably 50+psi) to support that load.

[prelude]

Quite interesting. I did not know the rubber was rated to 100 psi. My system pressurizes up to 150 psi, I believe that is the value of the cut-off switch. Of course, that much pressure is never applied to the airbags. I never measured the pressure on the bags when the car is loaded...

Anyway, if the bags are the limiting factor that would be a shame. I'm pretty sure other bags could be a workaround but this is starting to become a "redesign my car" job. I guess I'll have to start work on my air-rebuild project and insert pressure sensors to see how much pressure is on each line.

I have heard people about popping bags but I've never run into that problem myself before so I am not sure what causes it. I have been running a quite heavy laden vehicle (on gvm I would venture a guess) on pretty rough tracks (in europe, ok :P) but never had an issue. Perhaps someone can chip in with experiences in losing a bag on the road (or on the tracks).

My main concern right now is that quite a few "unsolvable" issues are rearing their head, particularly in the weight department. Running normal springs kinda defeats the purpose as far as I am concerned. I might as well jump ship to a car that has payload to begin with (110/130, LC 70 series?)

Cheers,
-P