Nose weights - Santa Fe

James3 · Mar 18, 2010

I know this has been covered several times on this forum and Lutz has also added his technical expertise but I am still confused.

Santa Fe has only 80kg nose weight allowance for the auto but much higher for manual. Lutz has indicated this is due to structural constraints but what does this mean ?

I understand max. towing weights being different from auto to manual but can't get my head around the reason for nose weight differences.

Can someone explain ?

john_5040775 · Mar 18, 2010

James, this question never seems to be answered. I contacted Hyundai and received a brief reply from it's Homologation Department. The reply was "4% is the ratio used between trailer weight and nose load and so as the trailer weight for the Santa Fe is 2500kg for the manual and 2000kg for the auto the nose load equates to :

4% of 2000kg (auto) = 80kg

4% of 2500kg (manual) = 100kg"

Hyundai has obviously used this method to calculate nose weight on previous models eg my '57 manual has a trailer weight of 2200kg and using the 4% figure gives a value of 88kg which is what is stated in the handbook. Not sure where this leads apart from the heavier the maximum trailer weight the higher the nose weight limit irrespective of any structural / suspension considerations.

xtrailman · Mar 18, 2010

That's interesting, obviously Nissan don't use 4%, my xtrail, max tow 2200kg, comes with 100kg nose limit.

Dare i say i would be tempted to ignore the 80kg and load up to 100kg.

Oldsalt49 · Mar 18, 2010

I'm with you on this one Ray. I have an auto santa Fee. It has the same rear suspension and rear axle as the manual, so can not see why there is a difference in nose weights. I have the workshop manual on cd, the rear springs and dampers are the same, except for the 7 seater which has self levelling dampers.

Lutz · Mar 18, 2010

I must say that the reply from Hyundai does them no credit. Normally, the manufacturers carry out durability tests on a shaker rig and gradually increase the noseweight until cracks appear in the underbody sheet metal. The limit will then be set at a level just short of this. To simply specify noseweight on the basis of a 4% formula is rather unprofessional on the part of their engineers.

James3 · Mar 18, 2010

Lutz

This is what is confusing me. If as you say these durability tests are made until some failure occurs and then the manufacturers then take a nose weight figure just below this why is the manual nose weight different from the auto. Surely the body construction is the same for both models ?

Whilst you disagree with the manufacturers taking 4% of the towing weight at least it does give some reason to the differences in nose weight.

Lutz · Mar 18, 2010

Yes, the 4% does explain why they specify a lower noseweight for the automatic than the manual, but it is a very poor explanation. As you say, the body construction is unlikely to be any different, so theoretically the noseweights should be the same, even if the towload limits are different.

Zafiral · Mar 18, 2010

4% is the legal minimum for noseweight. Are the figures the same for the new Kia Sorento?

However I would not recommend exceeding 80kg on the auto as you would then be towing illegally.

James3 · Mar 18, 2010

Nose weights same for new Sorento.

It does make me wonder if both the towing limits and nose weight figures have much technically verified data behind them. Are manufacturers using different criteria to establish these figures or what?

Lutz · Mar 19, 2010

From the reply John got from Hyundai, I would say that they are an exception.

James3 · Mar 19, 2010

I would love to know the calculations that are carried out by manufacturers. It is in their interests that any 4x4 can tow well so you would expect this to be an important part of the design. They would make the body construction so as to take fairly high nose weights (you would expect) in a similar vain they produce even more powerful diesel engines with loads of torque (new Santa Fe and Sorento over 200 BHP), which can obviously tow well. So the starting point must be what percentage of the kerb weight do they allow as a max. towing weight. What I find a bit strange that they seem to get very round up figures for max.towing weights such as 2500kg for manual and 2000kg for auto

For Hyundi and Kia this is quite important to get right because we have already seen many people on this forum say they would be ataying with the old Sorento because the new model does not have the towing capabilities of the old one.

I know the Santa Fe and new Sorento are quite different from the old Sorento models but you would expect towing to be a fairly key aspect in the design.

Lutz · Mar 19, 2010

Towload limits are normally determined by test, just like noseweight. I suspect that towing ability does not feature as a major priority in the design of most cars, other than true 4x4's, as a high towload obviously requires appropriate measures which inevitably cost money. It is doubtful whether a manufacturer would allow a product cost increase simply to satisfy those who wish to tow as the vast majority do not and they would not be prepared to pay the premium. Having said that, true 4x4's, being strong enough for off road use anyway, normally have towload limits well in excess of 100% of their kerbweight. On the other hand, SUV's which are not designed for serious off road use, are not subjected to such high loads except when towing, so the manufacturers are probably unwilling to make their designs suitable to tow heavier trailers.

ProfJohnL · Mar 19, 2010

Just to add, If manufacturers were designing vehicles for towing, at the very least the towing bracket would be built in and not an add on as it is with all domestic cars that I know of.

Gafferbill · Mar 19, 2010

I reproduce the following and give the source as The Camping & Caravanning Club....

It shows that ' a manufacturer's towing limit' does not mean what most people think it does and its method of calculation can vary to such an extent as to make comparisons meaningless!

"The manufacturer's towing limit is not set by issues of stability, simply by the car's physical capability.

In an ideal world, with perfectly surfaced roads, no crosswinds, air turbulence from speeding HGVs etc, then this limit could be used for matching purposes.

What the towing limit does give is an indication of the pulling power of the car.

Ideally, the weight of caravan should be below the towing limit by a reasonable margin - and more so when using an automatic car.

Trainweight or gross trainweight (GTW) is the maximum weight that a vehicle can move on the road, as stated by the manufacturer. This is the combined weight of vehicle and any trailer being towed and is the largest figure shown on the vehicle's VIN plate, which is usually found under the bonnet of the car.

The trainweight check is needed because the way the towing limit is set by manufacturers varies. Normally, the limit is set as the maximum weight of trailer that can be pulled away from a standing start on a 1 in 8 (12 per cent) gradient. Sometimes this limit is set when the car is fully loaded. Other times, depending on manufacturer or even model, the limit will be set with only a driver in the car or with a set number of passengers, but less than the full loading.

If you subtract the gross vehicle weight (the first figure on the VIN plate) from the trainweight (the second figure on the plate) you get the legal weight limit of trailer you can tow when the car is fully loaded. Hence, if the manufacturer has stated the towing limit when only the driver is present, then the subtraction from the VIN plate will give a much lower figure for the fully laden condition, but which is closer to the situation when the car is transporting the family and luggage.

When the manufacturer has stated the towing limit at the condition when the car is fully loaded, then the limit derived from the trainweight usually coincides with this stated towing limit".

Lutz · Mar 19, 2010

If the specified gross train weight is less than the sum of the gross vehicle weight and the towload limit, then this is an indication that the gross train weight is determined by braking performance rather than pulling power.

chenzhen · May 19, 2016

Search

Nose weights - Santa Fe

James3

john_5040775

xtrailman

Oldsalt49

Lutz

James3

Lutz

Zafiral

James3

Lutz

James3

Lutz

ProfJohnL

Gafferbill

Lutz

chenzhen

TRENDING THREADS

Latest posts