Weak when towing in low speed

[Billjohan]

When I was towing with a trailer loaded with some sand in an upphill road the Phev was very weak. I was even worried It would stop. I tried disconnect the engine as well as the the electric power but it was the same. i also tried to use 4 wheel drive only. When I told it to the garage when doing service they said that I have to live with that.

Is that really as it should be?

 

[Marksuk]

Personally I would not use it as a tow car, the limit is only 1500kg. I had a diesel before and it had much more "guts" than this phev. Having said that if the battery is charged and in use and the weight was not excessive I cant see why it would do this.

 

[jaapv]

Low down torque is very good, well over 300 Nm. On the Dutch forum somebody was using it to pull a 4000 Kg crane without problems. On the diesel version that would have burnt out the clutch. You completely lost me with the remark about disconnecting power???

The 1500. Kg limit is a legal one, btw, not a technical one.

 

[anko]

How steep an incline?
How much sand?
What was your SOC?

Personally, I haven't gone to the extreme although I was satisfied by how it towed my 1500 kg caravan to the Alps. Performance was just fine. Not being able to maintain SOC is more a slight concern to me.

A guy that did go to the extreme was this guy:

900 kg for the trailer
1700 kg for the digger
300 kg for the wood
2900 kg in total

He said there wasn't much reserve :mrgreen: But, he said, manoeuvring on electricity was great. At the end off the trip he had a steep incline to overcome. With any other car it would have cost him his clutch, he said.

 

[anko]

On the Dutch forum somebody was using it to pull a 4000 Kg crane without problems. On the diesel version that would have burnt out the clutch.

Hahaha. I guess we are talking about the same guy. But where did those 1100 kg extra come from? :lol:

You completely lost me with the remark about disconnecting power???

Same here.

 

[Billjohan]

Low down torque is very good, well over 300 Nm. On the Dutch forum somebody was using it to pull a 4000 Kg crane without problems. On the diesel version that would have burnt out the clutch. You completely lost me with the remark about disconnecting power???

The 1500. Kg limit is a legal one, btw, not a technical one.

Well I did not mean exactly disconnecting power what I ment was that I pressed the save button in order to use more of the non electric engine just to see if it made any difference but i did not

 

[Lyra252]

When I was towing with a trailer loaded with some sand in an upphill road the Phev was very weak. I was even worried It would stop. I tried disconnect the engine as well as the the electric power but it was the same. i also tried to use 4 wheel drive only. When I told it to the garage when doing service they said that I have to live with that.

Is that really as it should be?

Hi

I tow a 1500kg dive boat without any problems, keep the battery full and use save, the engine will run, but it's just powering the generator, or wheels, or both.

It's always 4wd, the lock button just sends the same power to the rear as to the front.

Cheers

Chris

 

[Billjohan]

When I was towing with a trailer loaded with some sand in an upphill road the Phev was very weak. I was even worried It would stop. I tried disconnect the engine as well as the the electric power but it was the same. i also tried to use 4 wheel drive only. When I told it to the garage when doing service they said that I have to live with that.

Is that really as it should be?

Hi

I tow a 1500kg dive boat without any problems, keep the battery full and use save, the engine will run, but it's just powering the generator, or wheels, or both.

It's always 4wd, the lock button just sends the same power to the rear as to the front.

Cheers

Chris

Ok good advices. I think I had almost full battery and tried to use the save button and I also pushed the button for permanent 4wd but nothing helped. Maybe I had 1000 kg as the most because it was avery small trailer that could not take more than a rather small tractor scoop

 

[anko]

Save would have been contra productive, but I am pretty sure the car will have ignored it. If the car was realy working that hard, the SOC must have been dropping despite selection of Save mode.

But can you tell us, was it realy weak, or did it maybe feel week because it was spinning at 4100 rpm, like a CVT would have done? How fast were you driving?

Edit - post on the Dutch forum by a guy from Belgium: he was in a PHEV that mastered an artificial slope of 70%, at low speed and without trailer of course. But also, without the ice kicking in.

 

[puckernutter]

Towing is never a problem. I have a friend who dragged his boat out of the water last year, you know from this slippery steep ramp where you reverse the trailer.

People stood there with their fossiles and burned clutch and rubber all day.

We just drove off in seconds after the boat was loaded on the trailer. I'd go for electric torque anyday.

 

[johanf]

I tow a 1500kg dive boat without any problems, keep the battery full and use save, the engine will run, but it's just powering the generator, or wheels, or both.
It's always 4wd, the lock button just sends the same power to the rear as to the front.
Cheers
Chris

Hi Chris or anybody else,
Is that 1500 kg including the weight of the trailer?
Will the PHEV be able to pull up a 1500 kg total weight 4 wheeled boat trailer on a sandy beach? We are using a Volvo XC90 diesel with manual gear today and it will do it easily. However, we consider to change to a PHEV and the brand new Volvo XC90 hybrid is way too expensive.
Regards
Johan

 

[maby]

I tow a 1500kg dive boat without any problems, keep the battery full and use save, the engine will run, but it's just powering the generator, or wheels, or both.
It's always 4wd, the lock button just sends the same power to the rear as to the front.
Cheers
Chris

Hi Chris or anybody else,
Is that 1500 kg including the weight of the trailer?
Will the PHEV be able to pull up a 1500 kg total weight 4 wheeled boat trailer on a sandy beach? We are using a Volvo XC90 diesel with manual gear today and it will do it easily. However, we consider to change to a PHEV and the brand new Volvo XC90 hybrid is way too expensive.
Regards
Johan

The 1500kg is the total rated towing capacity - Mitsubishi have no way of knowing if it is a big caravan, or a heavy boat on a light trailer. I assume that the figures relate to towing on a decent road surface - the same load on a soft surface such as sand could have a significantly higher rolling resistance.

 

[jaapv]

I tow a 1500kg dive boat without any problems, keep the battery full and use save, the engine will run, but it's just powering the generator, or wheels, or both.
It's always 4wd, the lock button just sends the same power to the rear as to the front.
Cheers
Chris

Hi Chris or anybody else,
Is that 1500 kg including the weight of the trailer?
Will the PHEV be able to pull up a 1500 kg total weight 4 wheeled boat trailer on a sandy beach? We are using a Volvo XC90 diesel with manual gear today and it will do it easily. However, we consider to change to a PHEV and the brand new Volvo XC90 hybrid is way too expensive.
Regards
Johan

The 1500kg is the total rated towing capacity - Mitsubishi have no way of knowing if it is a big caravan, or a heavy boat on a light trailer. I assume that the figures relate to towing on a decent road surface - the same load on a soft surface such as sand could have a significantly higher rolling resistance.

The 1500 Kg is a legal limit. It is the maximum load you may legally tow, but the car could handle more.

The Volvo 2.4 D3 XC90 has a max torque of 343 Nm, the PHEV 332. You should be fine.
At low speed/ driving off the PHEV has the clear advantage of the electric motors providing full torque from zero RPM. No risk of burning out the clutch. On soft sand do switch off the Stability Control and use 4WD lock.

 

[johanf]

... The Volvo 2.4 D3 XC90 has a max torque of 343 Nm, the PHEV 332. You should be fine ...

Thanks for answer.
But it is a D5 and it is rated 400 Nm.
However, isn't that torque measured at the motor shaft? In gear 1 it should be about 3 times more at the outgoing gearbox ...
But what matters should be the force on the wheels and then are the tyre radius and differential gear ratio effects included too. Then it is not the max torque at optimum rpm but a much lower rpm where the torque is less.
However, the electric motors do not have any gearbox increasing their torque.
Thus I find it quite complicated to foresee the abilities by the numbers above.
So, I would appreciate answers from practical use if you pull up boats on steep ramps or sandy beaches.
Thankful for your help! /Johan

 

[anko]

However, the electric motors do not have any gearbox increasing their torque.

This is not correct. It has one fixed gear ratio. Because of the extremely high max RPM and the limited top speed of the PHEV this one gear can be and is very 'short'. So, torque is increased by default.

Much of the 'high torque at very low speed' from ordinary cars requires a slipping clutch or torque convertor. And that will result in wear and tear of the clutch or heat built up in the convertor. The PHEV does not suffer from that.

 

[johanf]

Hi Anko,
So where is this torque measured then? The interesting torque needed in this situation is at the wheels in the lowest gear at very slow speed to pull the boat trailer up.

I guess a practical test is more interesting to hear about than any numbers. For instance; how steep can a PHEV climb fully loaded? Is it steeper or less steep than a diesel Outlander or Volvo? That could give an indication what to expect.

 

[anko]

At the motors.

Ratio front motor: 1:9.663
Ratio rear motor: 1:7.065

 

[jaapv]

... The Volvo 2.4 D3 XC90 has a max torque of 343 Nm, the PHEV 332. You should be fine ...

Thanks for answer.
But it is a D5 and it is rated 400 Nm.
However, isn't that torque measured at the motor shaft? In gear 1 it should be about 3 times more at the outgoing gearbox ...
But what matters should be the force on the wheels and then are the tyre radius and differential gear ratio effects included too. Then it is not the max torque at optimum rpm but a much lower rpm where the torque is less.
However, the electric motors do not have any gearbox increasing their torque.
Thus I find it quite complicated to foresee the abilities by the numbers above.
So, I would appreciate answers from practical use if you pull up boats on steep ramps or sandy beaches.
Thankful for your help! /Johan

A gearbox is meant to keep the engine at the revs needed to deliver full torque. Electric motors do not need a gearbox because maximum torque will be delivered as soon as they start to rotate.
However, you will notice that the electric motors can pull more power than the battery can deliver. For that reason the ICE will come in in series hybrid mode to supplement the power demand.
If you want to use the car this way (at high power) for a longer period of time without a chance to regenerate electricity you should start off with a well-charged battery.

 

[anko]

A gearbox is meant to keep the engine at the revs needed to deliver full torque. Electric motors do not need a gearbox ....

We may not need a gear box with different fixed or variable gear ratios to choose from. But we still need a gear box. Without a gear box, the e-motors would be running at about 1/10th of their normal rpm. And then they would be able to deploy their full power only at 560 km/h or more. And we want / need power as much as we need torque

Thanks to our gear boxes (we have one in the front and one in the back), we have 10 times more torque at the wheels, than we would have had without gear boxes. The price we pay is limited to speed.

 

[jaapv]

We'll, sure that is self evident. I probably should have said variable gear box