Towing Numbers

fla-gypsy wrote:
BenK gave you the answer, but as you can see some folks have their own ideas

So what does one do when a manufacture ONLY gives you the max trailer rating, and does NOT give you a gcwr. My Wifes ML 320 is this way. MB gives ALL the first versions a 5K trailer rating. With fine print in the owners manual, to get the BIGGEST motor for BEST performance towing. THey have the same statement in the newest ones, but the rating is 7500 from the 3.5LV6 the diesel, or the 5.5L supercharged v8 with double the HP and torque of the smallest V6 in the rig.

Even Bens answer, if someone really wanted to, one can blow holes in his description also! If one has a rig at GVWR, per Ben, you can subtract the gvwr from the gcwr, and still tow that amount, granted you have no HW, which will cause for an unstable tow! in fact probably unsafe.......

Then one thing he says one needs to look at, paraphrasing, is one has to look at ALL the numbers together! to use ONLY one per say, will get you in trouble. Then if one uses the new SAE spec, max grade in first gear tested to is 12%. If you need to go up a 30% grade, yeah on the steep side, but I know where a few driveways, and side streets are, if you are a contractor like me, that has to follow the manufacture gcwr, you will not get your equipment to the job site if you stall out on that 30% grade. Hence why MDT and HDT trucks have individual gcwr's based on the end user of that truck! Some trucks have drive trains ONLY ment to mover the gvwr down the road, others are setup to move 80K on freeway grades with a max gradability of 15%, meanwhile a dumptruck or cement truck, will have gradiblities to 80%, and can only move an 80K load at 45 up a 3% grade, The otr rig will move said 80K rig up the 3% grade at 55-60 mph! IE it will have more hp and gearing to move the load on a freeway. THe dump truck is setup for more slow speed with occasional freeway useage.

More than one way to skin a cat!

Marty