Xantia 1.9 TD Auto towing weight

[G3VKI]

I have a Citroen Xantia 2000 (W reg) 1.9TD auto, and the manufacturer's handbook gives the towing limit as 900KG, although all other models in this range have a towing limit of 1200KG.

This is considerably less than 85% of the unladen weight of the vehicle which is 1336KG. In fact the manufacturers handbook says that the towing limit in France for this model is 1200KG!

Diesel auto is claimed to be the best combination for towing; why is the towing limit so much lower for the diesel auto and is there a modification that would allow it to legally tow the extra weight? Also, does anyone know why the weight limit is different in France?

[CitroJim]

Welcome to the Forum G3VKI. I guess you're a radio amatuer. Me too but very inactive nowadays; Citroens consume all my time

The towing limit will be down to the gearbox fir and square. The car whas the Siemens AL4 electronic 'box and these, along with their bigger bretheren, the 4HP20, are a bit sensitive to excess heat. Cooling is a bit marginal at best and the AL4 is near it's torque limit anyway with a TD engine behind it.

The AL4 has a water:oil heat exchanger for cooling and heat from the 'box is dumnped into the cooling system. When this is hot from towing, gearbox colling will be coompromised.

Clutch slip is unlikely to be a problem when towing with the AL4 but increased heat produced by the Torque Convertor could well be the limiting factor.

I reckon if you were to improve gearbox cooling, say by using a larger air:oil exchanger you'd be OK for towing. I'd be tempeted to fit a transmisssion fluild temperature gauge for safety but do be aware that the AL4 has an internal temperature sensor and if this detects a dangerous fluid temperature it will throw the 'box into third emergency ("limp home") mode. You definitely don't want this happening when towing.

Interestingly, the V6 Xantia with the bigger 4HP20 autobox has similarly restricted towing capacity. I suspect that the same heat restraints apply as yours. If you saw the gearbox itself, you'd see it's built like a brick outhouse and well up to the job mechanically...

[jgra1]

hmm slightly off topic....

Jim.. I was thinking of occasionaly using my 4hp20 coupe to tow the boat.. Boat and trailer probably only 500kg but.....

suppose I have a spare box

[G3VKI]

Welcome to the Forum G3VKI. I guess you're a radio amatuer. Me too but very inactive nowadays; Citroens consume all my time

The towing limit will be down to the gearbox fir and square. The car whas the Siemens AL4 electronic 'box and these, along with their bigger bretheren, the 4HP20, are a bit sensitive to excess heat. Cooling is a bit marginal at best and the AL4 is near it's torque limit anyway with a TD engine behind it.

The AL4 has a water:oil heat exchanger for cooling and heat from the 'box is dumnped into the cooling system. When this is hot from towing, gearbox colling will be coompromised.

Clutch slip is unlikely to be a problem when towing with the AL4 but increased heat produced by the Torque Convertor could well be the limiting factor.

I reckon if you were to improve gearbox cooling, say by using a larger air:oil exchanger you'd be OK for towing. I'd be tempeted to fit a transmisssion fluild temperature gauge for safety but do be aware that the AL4 has an internal temperature sensor and if this detects a dangerous fluid temperature it will throw the 'box into third emergency ("limp home") mode. You definitely don't want this happening when towing.

Interestingly, the V6 Xantia with the bigger 4HP20 autobox has similarly restricted towing capacity. I suspect that the same heat restraints apply as yours. If you saw the gearbox itself, you'd see it's built like a brick outhouse and well up to the job mechanically...

Hello CitroJim, and thanks for your help. You're right about my being a Radio Amateur, but I've been inactive since about 1987. Nowadays I just use my call sign as a convenient short username.
I thought cooling may have been the issue, but if I simply arranged better cooling and then towed above the 900kG limit, wouldn't this give my Insurance co the chance to wriggle out of a claim?
The thing that intrigues me most though is why the limit is 300kG higher in France.

[MikeT]

I have a Citroen Xantia 2000 (W reg) 1.9TD auto

Sorry for being off-topic, just a quickie. Is it an estate by any chance?

[G3VKI]

I have a Citroen Xantia 2000 (W reg) 1.9TD auto

Sorry for being off-topic, just a quickie. Is it an estate by any chance?

Hatchback, does this make a difference?

[CitroJim]

Jim.. I was thinking of occasionaly using my 4hp20 coupe to tow the boat.. Boat and trailer probably only 500kg but.....

Shouldn't be a problem John

Rebuilds are undertaken you know

The thing that intrigues me most though is why the limit is 300kG higher in France.

They may have had a different method of calculating it. Manufacturers towing limits have little relevance to real world towing limits. I believe the manufacturers ones are based on the ability to hold and start off on a given (steep) gradient. It follows that an automatic is likely to suffer torque converter slip and an inability to hold steady on a steep gradient under such circumstances and thus the weight limit is defined. French and British test gradients may differ. Ours I fancy is a 1 in 3 gradient. Who in their right same mind goes near such a hill in real life?

As for insurance, provided you are observing the 85% "rule" (recommendation) and observing the correct nose, train weights and trailer MGW, I don't think there will be an issue here. get the cooling sorted and away you go...

You will find the Xantia to be an excellent towcar; I used a 1.9TD to tow a caravan for several years.

[G3VKI]

The thing that intrigues me most though is why the limit is 300kG higher in France.

They may have had a different method of calculating it. Manufacturers towing limits have little relevance to real world towing limits. I believe the manufacturers ones are based on the ability to hold and start off on a given (steep) gradient. It follows that an automatic is likely to suffer torque converter slip and an inability to hold steady on a steep gradient under such circumstances and thus the weight limit is defined. French and British test gradients may differ. Ours I fancy is a 1 in 3 gradient. Who in their right same mind goes near such a hill in real life?

As for insurance, provided you are observing the 85% "rule" (recommendation) and observing the correct nose, train weights and trailer MGW, I don't think there will be an issue here. get the cooling sorted and away you go...

You will find the Xantia to be an excellent towcar; I used a 1.9TD to tow a caravan for several years.[/quote]
Was that with a manual or auto gearbox, and how heavy was the caravan?

[MikeT]

I have a Citroen Xantia 2000 (W reg) 1.9TD auto

Sorry for being off-topic, just a quickie. Is it an estate by any chance?

Hatchback, does this make a difference?

No, it's purely for my own interest. I'll butt out now, thanks for answering.