GrenX Ineos Grenadier 68L Auxiliary Fuel Sub Tank Brown Davis

[GrenX]

Sharing an update on development of the auxiliary fuel tank for the Ineos Grenadier. Here is the 2nd iteration prototype being test fitted before the final design is set. 68L GrenX

 

[Ex-defender driver]

Sharing an update on development of the auxiliary fuel tank for the Ineos Grenadier. Here is the 2nd iteration prototype being test fitted before the final design is set. 68L GrenX

Hi - Whose making this and where can we buy one??? Perfect solution for the small tank and the Grenadier.

 

[Clark Kent]

Brown Davis in Knoxfield.
Listed here.

 

[anand]

Anyone happen to know if they are also doing a petrol tank as well?

 

[Ex-defender driver]

Brown Davis in Knoxfield.
Listed here.

Thanks

 

[Clark Kent]

Hi - Whose making this and where can we buy one??? Perfect solution for the small tank and the Grenadier.

I'm interested in people's thoughts on this.

It's 68lts (17.9 USG) of fuel plus the tank weight, and located behind the rear axle where it replaces the muffler. I haven't gone back to check, but I recall Robert Pepper thought the rear axle was already a bit down on load capacity plus the weight behind the axle likely reduces the towball limit. I would like to see some calculations on this from Brown Davis so buyers can make an informed decision. The extra range is nice to have but what's the operational impact of fitting this tank?

 

[grnamin]

I'm interested in people's thoughts on this.

It's 68lts (17.9 USG) of fuel plus the tank weight, and located behind the rear axle where it replaces the muffler. I haven't gone back to check, but I recall Robert Pepper thought the rear axle was already a bit down on load capacity plus the weight behind the axle likely reduces the towball limit. I would like to see some calculations on this from Brown Davis so buyers can make an informed decision. The extra range is nice to have but what's the operational impact of fitting this tank?

Will shocks need to be upgraded to accommodate the extra weight of a full tank?

 

[Clark Kent]

Will shocks need to be upgraded to accommodate the extra weight of a full tank?

There is at least one approved GVM upgrade kit available in Australia (3550kg to 3800kg) which is springs and shocks (Kings or Koni) and that would offset the gain in tare (kerb) weight and loss of payload due to this tank. Rear axle limit is another question.

The economic benefit is a separate issue. The tank is around A$2k plus fitting costs and I believe the GVM kit runs around A$5.5k, so the investment to gain the extra range is starting to add up if springs and shocks are required.

My diesel Grenadier runs around 11.5 lts/100km (22 US MPG) at touring weight and 16.8 lts/100km (14 US MPG) if I'm towing as well. Assuming all 68 litres in this tank are useable I would gain another 618km theoretical touring range (not towing). In practice it will be less because I would be carrying the dead weight of the tank and fuel. Call it an optimistic 600km. Let's say I install the tank myself to avoid the fitting costs and this solution would cost me A$2k to gain around 600km range. More if new shocks or a full GVM kit is required. For remote touring A$2k is probably acceptable given the range limits of the 90 litre factory tank. At $7.5k with a GVM upgrade it's getting expensive. Each to their own though.

 

[Tinerfeño]

Will shocks need to be upgraded to accommodate the extra weight of a full tank?

This is a very common misundeerstanding. Springs carry the load, not shock absorbers, which only dampen the movements of the axle in relation to the chassis. Gas filled shocks carry a very minor part (<5% ) of the weight,

Any GVM uprate kit may also require higher load rating of the tyres. Not likely but possible, Axle capacity is hard to verify.

 

[Znarfgh]

Will shocks need to be upgraded to accommodate the extra weight of a full tank?

Probably not but your rear springs will need to be upgraded especially if you are towing and have drawers in the back. I only have 150kg of ball weight and feel like I need longer or stronger springs.

 

[Clark Kent]

This is a very common misundeerstanding. Springs carry the load, not shock absorbers, which only dampen the movements of the axle in relation to the chassis. Gas filled shocks carry a very minor part (<5% ) of the weight,

Any GVM uprate kit may also require higher load rating of the tyres. Not likely but possible, Axle capacity is hard to verify.

There's an interesting side question: We know that Ineos supply different spring rates according to the customer's order; mostly around the winch, towing and roo bar (Aust.) options, but is there any data on matched shock absorbers? I don't recall the spread of spring rates available, but it's possibly not significant enough to require matched shocks to avoid over/under damping.

With this aux tank upgrade I could foresee potential issues with a vehicle that was delivered with light duty springs dealing with the weight and pitching moment created by ~100kg of fuel and tank sitting behind the rear axle, plus any fitout and payload.
Brown Davis have been designing, building and installing long range tanks for a long time so I'm sure they're on top of this.

 

[Tazzieman]

Probably not but your rear springs will need to be upgraded especially if you are towing and have drawers in the back. I only have 150kg of ball weight and feel like I need longer or stronger springs.

I will probably just get a pair of airbags ; I have around 250kg on the towball (hybrid caravan) and I feel that's about the upperl limit for stock suspension.

 

[GrenX]

Anyone happen to know if they are also doing a petrol tank as well?

I will be also trying to get a solution for the petrol version. My GrenX development vehicle will be completed this week with brown davis. With the tank is installed and next stop will be the 45mm upgrade eibach springs, if i plan to tow a van i would get some rear airbags but at this point I will not be towing more than 1.5t. And possibly a set of Koni Raid 90 Shocks will go in later in the year.

 

[NQ94]

It would be interesting to know how much hotter the tail pipe outlet temperature is during a DPF burn on a diesel with out the large silencer and dual outlets.

For the Aussie owners as an option maybe approaching a company like Dobinsons in Qld to make a rear set of springs suited to the fuel tank upgrades and peoples towing requirements this may be also a more cost effective solution for getting spring rates right for the QM when it is released and modified for touring. Dobinsons make coil springs including custom springs for industry and vehicles.

 

[[ Adam ]]

Anyone happen to know if they are also doing a petrol tank as well?

Very much seconded. Nearly doubling the fuel capacity would be stellar.

As GVWR steadily increases, I think if I ever acquire a travel trailer, it'll have to be something super light like a Basecamp 16x. Sadly - I don't think the Grenadier will handle my dreams of a Palomino Pause 16.4.

Regardless - more fuel will be required!

 

[anand]

As GVWR steadily increases, I think if I ever acquire a travel trailer, it'll have to be something super light like a Basecamp 16x. Sadly - I don't think the Grenadier will handle my dreams of a Palomino Pause 16.4.

I think it would handle a Basecamp 20X wonderfully as well (not having walked into either before, but spent lots of time ogling, and personally like the separate spaces of the 20).... Technically, the Palomino falls under the max towing weight, so it could pull it

 

[TCMColorado]

It is only a matter of time before springs with different rates are offered by the usual providers that will allow matching of spring rate to payload. ARB/OME will likely be one of the first to have complete lift kits with matching shocks and multiple spring options. A higher spring rate will easily accommodate this tank. And for the US market a GVM upgrade is not a required consideration.

 

[Clark Kent]

It is only a matter of time before springs with different rates are offered by the usual providers that will allow matching of spring rate to payload. ARB/OME will likely be one of the first to have complete lift kits with matching shocks and multiple spring options. A higher spring rate will easily accommodate this tank. And for the US market a GVM upgrade is not a required consideration.

There is a range of springs rates fitted at the factory, table here, plus the Eibach pro lift kit is available.

US market sales will generate good aftermarket investment. The AU/NZ market has 1300 Grenadier sales (to end March) so there is not a lot of big brand interest at this stage. A few small outlets and agents are offering curated solutions.

 

[Znarfgh]

I will probably just get a pair of airbags ; I have around 250kg on the towball (hybrid caravan) and I feel that's about the upperl limit for stock suspension.

I have airbags in my old D2 and whilst they are good for limiting rear end droop they do limit spring compression and make the ride harsher in the back. Having had this setup before, it's not ideal.

I'm going to see a spring maker at some point and will give him all the data from my existing springs plus what the weight of my rear storage system and tow ball downforce. He then calculates the required spring lengths and makes them up for me. With my Disco I had standard spring ride comfort with a 2" lift and ability to carry my additional loads. At that stage I did not have a van and when I did get one, I needed airbags to get the vehicle level when towing. A set of custom springs will probably cost about the same as the airbags. Anyway, it's on my to do list but not as a matter of urgency.

 

[LeftCoastOverland]

Perhaps A more cost effective and less permanent solution to the problem… Fuel Bladder