Re: Wheel base - Mini Van versus Trailblazer
#1,
Your weight ratings posted have to do with licensing, not towing laws. A man with a CDL who is licensed to tow 80,000lbs DOES NOT HAVE THE RIGHT TO TOW IT WITH A PT CRUISER!
according to the DEPARTMENT OF TRANSPORTATION's website you MUST follow the manufacturers posted GVWR.
Here is the link and its to the DOT website, not some retarded RV site. Last I checked, the DOT is the law, not the local RV center.
http://www.nhtsa.dot.gov/cars/problems/Equipment/towing/if_you_have.htm
Here is a pretty PDF document the NHTSA and DOT have put together for women, children and you.
http://www.nhtsa.dot.gov/cars/problems/Equipment/towing/Towing.pdf
Now, if you HONESTLY think the engineers design the vehicle and the ACCOUNTING!!!! department decides how much it can tow, then you need a CAT scan.
Here is another good read for you: and I quote
"The limitations are stamped on a "Tire and Loading Information" plate on the driver's side door frame. The ratings are an outgrowth of the 2000 Firestone tire recall, in which overloading was considered a factor that could cause tires to fail. Weight limits are important because automakers could claim they don't have responsibility for a component failure or a crash if a vehicle is overloaded. The National Highway Traffic Safety Administration says automakers can set the weight limit at whatever they deem appropriate.
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Your quote:
"As to what the PT cruiser will do in the mountains...it has 220 hp and weighs half of an f350. If an f350 with 440hp can do it, so can a pt cruiser with 220. Same hp/weight ratio."
OMF'in GOD! This is the dumbest thing I have read in a LOOONNNGGG time! SO what you are saying here is if we hooked the back of a PT cruiser to the back of an F350, we would have an even pull? A tire spinning standoff? How many F350 owners on this forum just pissed their pants laughing?
So Chrysler Engineers gave the PT cruiser a 1,000lb tow capacity and the Ford engineers gave the F350 up to 16,000lbs tow capacity, but according to you and your "rv buddies" they actually can pull the same?
Further more, horsepower has nothing to do with getting that vehicle/trailer moving, its all about the torque.
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Your quote:
"As for at the boat ramps, I'd rather have a FWD with limited slip and/or traction control than a RWD vehicle with an open differential. With the FWD you would have power going to both tires, with more power going to the wheel with the most traction. With a RWD vehicle with an open differential you get power to only one tire, the one with the least traction."
First off, do you know the difference between a limited slip, posi traction, traction control and a locking diff? 90% of all FWD passenger cars have no traction device with exception of their version of a traction control, which only reduces spinning by way of "drive by wire". It does not increase traction, it just helps to prevent a spinning tire. In my extensive automotive history I know of NO passenger FWD vehicle with a posi or limited slip diff. I know for a fact that no passenger vehicle with FWD has ever been available with a locking diff (automatic or manual)
Ever played on a seasaw? Do you know what a fulcrum is?
If you take a PT cruiser and place a boat on the rear, give it a 200lb tongue weight and 3000lb trailer weight. Back it down a boat ramp. The boat weight and tongue weight presses down on the rear, LIFTING the front where all the traction would be.
Make that a RWD vehicle and the increase in tongue weight HELPS to gain traction, by forcing the rear driven tires down more.
THIS is why 5th wheels are the highest tow capacity on the road (passenger vehicle). It places the tongue weight directly over the axle. Hard to put a 5th wheel on the hood of a PT cruiser!
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Your quote:
"DRAG coefficient has NOTHING to do with brakes, Nothing! Do you mean the coefficient of friction of the tires? And there is definitely more to it than just the coefficient of friction. It is the weight that has to be stopped, which is why the Corvette takes 40% less distance to stop from 60 mph than an f350. Weight is not a good thing when it comes to braking efficiency. It is a BAD thing. Why do you think 18 wheelers take such a long time to stop?????"
I incorrectly typed drag coefficient instead of coefficient of friction; however the principal is correct. The coefficient of friction of the tow vehicle is limited by the tire contact to the pavement and the force applied (vehicle weight) once you exceed that, you have lost your friction or ability to stop the weight. The friction cofficient of a PT cruiser under braking is far less than the full size truck. Same reason to your example, why do you think an 18 wheeler has 18 wheels?
A standard vehicle has approx 70% of its braking power on the front tires and the remaining 30% on the rear. The reason for this is because there is more weight in the front and the weight of the vehicle transfers forward under heavy braking. Were back to friction coefficient, more ability for the front tires to assist in the stopping as it has more force holding them down.
Trucks and SUV's are designed in many ways to handle more weight rather that be cargo or towing. Trucks and SUV's have load sensing proportioning valves and have for YEARS! Some are manual, a rod connecting the rear axle to the valve on the frame and some work more like a bubble level, senses the tilt of the vehicle.
When a truck or SUV is loaded with cargo or a trailer, the valve adjusts applying MORE brake ability to the rear wheels, because they have more weight holding them to the pavement and therefore can help more.
Depending on which generation, and which package Vette, the brake materials are much different from any standard truck/SUV. Vette's can have anything from Carbon rotors to magnesium calipers.
Whats important is that they have huge vents and thin rotor walls! Where a truck has average vents and THICK rotor walls.
Vette brakes are designed to stop its own weight and fast from higher speeds. They are designed to only get but so hot because of maximum ventilation. Some Vette's actually have ducts running from the front airdam to the rotors to keep them cool. If that same vette was pulling 2500lbs and tried to stop at the same rate, they would overheat quickly causing the pads to gas.
A truck/SUV handles the heat differently. With thick rotor walls made of steel, it can absorb the heat and cool on a more average speed. Quick cooling causes warped rotors (not excessive heat) Trucks and SUV's have brakes designed to run hotter for longer periods of time.
In addition, Trucks and SUV's have transmissions designed to assist and use engine back pressure to reduce the speed of the towing vehicle. I have YET to to this day find a Vette with a "tow/Haul" button on the shifter!
To compare the brakes on a Vette vs any Truck/SUV is like comparing apples to roof shingles. The only thing similar about them is that they are designed to stop a vehicle.
