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Handle9
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  #3078829 23-May-2023 00:28
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Wheelbarrow01:

The weight of what you are towing isn't the only consideration - don't forget gross vehicle mass (GVM) and gross combination mass (GCM).


Th Outlander LS has a curb weight of 2020kg. GVM is 2650. The difference is 630kg - the weight you can't exceed for all occupants + fuel + whatever you have in the boot (and/or on the roof). If you do, you've technically already overloaded it before you even hook a trailer on.


Gross combination mass limit for the LS is 4250kg (curb weight + max onboard load + max trailer load).


I just thought I'd mention it as many people mistakenly believe they can just remove 100kgs or so from a too-heavy trailer/caravan and just add it to whatever is already in the boot/on the roof of the tow vehicle, to bring the trailer under the max tow rating, but that action can exceed the vehicle's GVM, leading to sprung weight that may not be able to be controlled in heavy cornering, emergency/evasive braking etc.


I'm no expert, but John Cadogan is - not strictly relevant to this conversation but his video about overloaded utes is a real eye opener.


 



Don’t forget the tow ball load counts towards GVM. For a 1100kg trailer that’s typically 110kg.



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  #3078891 23-May-2023 08:33
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Thank you all for your replies! Some very good information and considerations here.
Ultimately sounds like I may be right on the limit to what I want to do here and need to step up to something with a larger tow capacity.
We have a mitsubishi dealer down the road so will pop in there and have a yarn to them too.




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  #3078985 23-May-2023 13:17
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tweake:

 

unihubs require a press to install them. so replacement is a major and considering how boat trailer bearings typically die, i do not think they will last any longer.

 

my other advise is to have two hydraulic lines for the brakes and make sure everything is even. i find the first brake on a single line circuit is the one that wears out the most. also if possible plumb it to the rear brakes first, which helps make them engage first which helps with trailer stability. 

 

 

Good points, thanks. I have access to hydraulic press with a bunch of mandrels at work, so no worries there. 

 

The performance of uni-hubs is all dependent on the quality of the seals, I guess.  There is a triple lip rear seal, plus the bearings themselves are sealed, plus an o-ring on the dust-cap.

 

I've heard that a few boat trailer manufacturers have started using them.

 

I'll give the brake plumbing some thought.  I have to have one line per side, because of the trailer configuration.   I can tee each side with a shorter line to the rear brakes so they activate first.

 

Edited for clarity





Mike




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  #3078989 23-May-2023 13:41
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Wheelbarrow01:

 

The weight of what you are towing isn't the only consideration - don't forget gross vehicle mass (GVM) and gross combination mass (GCM).

 

 

 

Th Outlander LS has a curb weight of 2020kg. GVM is 2650. The difference is 630kg - the weight you can't exceed for all occupants + fuel + whatever you have in the boot (and/or on the roof). If you do, you've technically already overloaded it before you even hook a trailer on.

 

 

 

Gross combination mass limit for the LS is 4250kg (curb weight + max onboard load + max trailer load).

 

 

 

I just thought I'd mention it as many people mistakenly believe they can just remove 100kgs or so from a too-heavy trailer/caravan and just add it to whatever is already in the boot/on the roof of the tow vehicle, to bring the trailer under the max tow rating, but that action can exceed the vehicle's GVM, leading to sprung weight that may not be able to be controlled in heavy cornering, emergency/evasive braking etc.

 

 

 

I'm no expert, but John Cadogan is - not strictly relevant to this conversation but his video about overloaded utes is a real eye opener.

 



 

On utes, the overloading issue is that the Thai built ute's typically have a GCM that is 500kg+ less than the GVM + tow rating. This means if you want to tow the limit, the Ute can only be fairly lightly loaded (and ideally predominantly loaded in the cab not the tray).

 

 

 

With the outlander PHEV, per the above number's, you can tow the full tow rating, without needing to reduce the payload of the tow vehicle.

 

Main issue with big(ish) towing with soft SUV's is rear axle load. 100+ kg on the towball, plus a loaded boot will lead to problematic tail sag.

Should note that many euro caravans are set up with a 5% towball downforce, which improves this issue (but decreases stability at high speeds, keep under the 90km/h limit).

nzpilot1181: Thank you all for your replies! Some very good information and considerations here.
Ultimately sounds like I may be right on the limit to what I want to do here and need to step up to something with a larger tow capacity.
We have a mitsubishi dealer down the road so will pop in there and have a yarn to them too.

 

If the van is 1100kg loaded (and breaked), and your budget can accommodate a 1500kg / 1600kg tow rated outlander PHEV, you are well inside the rating, And barely above half the empty weight of the Outlander PHEV. For me this is heaps of fat.

If the van  is 1100kg empty (say 1400kg full), then yeah, you are approaching the upper limit of your tow vehicle (assuming you can keep the rear axle load manageable). But still, your trailer weight is quite a bit lower than the weight of your two vehicle, which is good.

I tow the full 1500kg that my Lexus SUV (similar size and weight as an Outlander PHEV) is rated for. I put coil helpers in the back to mitigate some of the tail sag (I am aware that doesn't change the rear axle load rating, but it helps keep the suspension geometry better), and am pretty mindful that I am operating near the limit (that trailer has a big nose down force), and drive with that in mind. The rig simply isn't going to handle, stop etc as well as an empty car, so longer following distance, and more aggressive defensive driving are needed).

Of course something like a Pajero sport or Landcruiser would be a lot more desirable, but I simply can't justify the higher capital cost, higher running costs, and decreased performance for the handful of times I tow a year.


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  #3079048 23-May-2023 15:14
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MikeAqua:

 

Good points, thanks. I have access to hydraulic press with a bunch of mandrels at work, so no worries there. 

 

The performance of uni-hubs is all dependent on the quality of the seals, I guess.  There is a triple lip rear seal, plus the bearings themselves are sealed, plus an o-ring on the dust-cap.

 

I've heard that a few boat trailer manufacturers have started using them.

 

I'll give the brake plumbing some thought.  I have to have one line per side, because of the trailer configuration.   I can tee each side with a shorter line to the rear brakes so they activate first.

 

Edited for clarity

 

 

hot bearings and cold water will suck water in past any seal.

 

line per side is great, i wish they did that on ours. it was forever wearing out one brake pad. i would run the line to the rears then T and run a line back to the front. i have toy'ed with the idea of a balance line. ie connect each side at the back (with bleeder in the middle). not sure how useful that would be.


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  #3079132 24-May-2023 08:03
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tweake:

 

my other advise is to have two hydraulic lines for the brakes and make sure everything is even. i find the first brake on a single line circuit is the one that wears out the most. 

 

 

Are you sure? The beauty of a hydraulic system is that the pressure at each piston should be equal regardless of variations in the length of the hydraulic lines. Car manufactureres make no effort to ensure that hydraulic lines are equal. Think front brakes on a car where the master cylinder is closer to the R front wheel and the length of the brake line is always shorter than to the L front. I have worked on numerous vehicles where the brake line is taken to say the R rear, then from the wheel cylinder across the rear axel to the L rear. Is it possible you had another problem? eg sticky cylinder?

 

Sorry for the off topic. 


 
 
 

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  #3079141 24-May-2023 09:11
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tweake:

 

hot bearings and cold water will suck water in past any seal.

 

 

I do wonder about that. The rear seal doesn't look substantially different from ye olde trojan kit. They do say the bearings are sealed, but I don';t know what that actually means - water proof or dust proof?   

 

I take my time in the staging area, getting my boat ready doing prechecks etc before I launch. After all that, it's a good 15-minutes and the hubs are ambient.  Maybe I'll just stick with my bearing buddies.

 

 





Mike


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  #3079402 24-May-2023 15:13
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MikeAqua:

 

I take my time in the staging area, getting my boat ready doing prechecks etc before I launch. After all that, it's a good 15-minutes and the hubs are ambient.  

 

 

i would keep doing that, its a good practise. 


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  #3079410 24-May-2023 15:39
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traderstu:

 

tweake:

 

my other advise is to have two hydraulic lines for the brakes and make sure everything is even. i find the first brake on a single line circuit is the one that wears out the most. 

 

 

Are you sure? The beauty of a hydraulic system is that the pressure at each piston should be equal regardless of variations in the length of the hydraulic lines. Car manufactureres make no effort to ensure that hydraulic lines are equal. Think front brakes on a car where the master cylinder is closer to the R front wheel and the length of the brake line is always shorter than to the L front. I have worked on numerous vehicles where the brake line is taken to say the R rear, then from the wheel cylinder across the rear axel to the L rear. Is it possible you had another problem? eg sticky cylinder?

 

Sorry for the off topic. 

 

 

actually manufactures do put some effort in. you will often see a coil of brake line, especially drivers front wheel.  

 

in normal operation when your putting a decent load on the hydraulic system, yes it will balance across all the brakes. however what happens under light braking is the easiest one to move, moves first. keep in mind that hydraulic lines are resistance to flow.  if all the other brakes have more resistance than one brake, that brake will be pushed on first.  that brake pad will push against the disk, but there is not enough force in the system to push the other brake pads onto the disks. the pressure is very light, but enough to cause the pad to rub. every time it does it its a tiny amount of wear, and because its the same pad every time that one will wear more than the others.

 

the other issue is when coming off braking. the other brakes are pushing fluid back up the line. so you can have 3 brakes feed back to one brake which is going to keep the pad on the disk a little bit longer. what i suspect compounds it a bit is that trailer master cylinders are not fixed to the actuator as such. so the brakes get pushed on, but they only return due to the oring on the pistons and wobble on the disk due to the bearings.

 

overall result is one pad/brake tends to wear out faster, which is exactly the issue i've had on our trailer. the first brake in the circuit wears out quicker than the others.

 

 


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  #3079416 24-May-2023 15:59
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tweake:

 

MikeAqua:

 

I take my time in the staging area, getting my boat ready doing prechecks etc before I launch. After all that, it's a good 15-minutes and the hubs are ambient.  

 

 

i would keep doing that, its a good practise. 

 

 

It's inevitable. My main fishing buddy is female and the boat has zero privacy for ablutions.  She always has a toilet stop at the boat ramp.





Mike


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  #3100099 5-Jul-2023 10:12
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Hi All,

Just additionally to my original query, what would happen if you had depleted the battery prior to a long hill climb with a caravan? The model I am looking at is 2.4 litre so presumably there would be no issue as I would be using purely just the petrol engine like any othet vehicle? Is my thinking correct?




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  #3100166 5-Jul-2023 12:39
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nzpilot1181: Hi All,

Just additionally to my original query, what would happen if you had depleted the battery prior to a long hill climb with a caravan? The model I am looking at is 2.4 litre so presumably there would be no issue as I would be using purely just the petrol engine like any othet vehicle? Is my thinking correct?


In that case your 2.4 petrol will pull the car, the occupants and their luggage, the caravan, and the battery pack, up that hill.

Edd

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  #3103150 12-Jul-2023 13:11
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nzpilot1181: Hi All,

Just additionally to my original query, what would happen if you had depleted the battery prior to a long hill climb with a caravan? The model I am looking at is 2.4 litre so presumably there would be no issue as I would be using purely just the petrol engine like any othet vehicle? Is my thinking correct?

 

Some extra background on how the hybrid system works in the PHEV: In normal use the battery never goes much below 30%; if you drive in electric mode down to that point the ICE will fire up and from then on the car will run as a hybrid (alternating between electric and ICE as waste energy goes into the battery) and maintain that minimum buffer.

 

Under load there's less waste energy so I've seen mine using both ICE and electric motors on hill climbs (not towing, just moderately loaded) with the battery SoC going as low as 20%. The good news is when you roll down the other side, the regen charges the battery very quickly! However, I'm not sure how low the car will allow the SoC to go, or if there's some sort of turtle mode if it gets too low.

 

The other thing to remember is below about 70kph the drivetrain runs in series mode (ICE charging the battery powering the electric motors). So if you're towing uphill below that speed and completely deplete the battery you may have a major problem. As others have said earlier, the answer to that is to use the charge button (or stop and fast charge) before the climb to make sure you have a high enough SoC to get to the top.

 

See this FAQ for an explainer of how the series/parallel drivetrain works.


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