M

 

 

MAGS

A wheel cast in magnesium, then machined for attachment to hub, etc. Used primarily for racing because of extremely light weight, but sometimes used or simulated to add a racy appearance.

 

MAIN FRAMING

See Body Framing

 

MAIN IRON

(Slang) Main track.

 

MAIN RESERVOIR (air brake)

A tank on an engine for storing the main air supply.  So called in distinction from the auxiliary reservoirs under each car.

 

MAIN TRACK

A designated track upon which trains are operated by timetable, train order, or both, or the use of which is governed by block signals.  

Maintenance Visual Reminder
When any maintenance limit has been approached within a preset percentage, the Check Engine Light will blink, six times each time the ignition key is turned from off to o n. ( Detroit )

MANIFEST

A document describing a shipment or the contents of a vehicle or ship.

 

MANIFOLD

The connector which ducts the gas from the inflator to the diffuser and air cushion assembly.

 

MANNER OF COLLISION

Applies to accidents in which the first harmful event was a collision between two motor vehicles in transport and is identified as one of the following;  1) angle: a collision of the front of one vehicle with the side or corner of another.  2) Head-on:  a collision of the front end of one vehicle with front end of another vehicle while the two are traveling in  opposite directions. 3) sideswipe:  a collision of two vehicles in which the sides of both vehicles sustained minimal engagements, 4) other: any collision not classifiable as one of the above.

 

MANUAL BLOCK SIGNAL SYSTEM

A block signal system wherein the use of each block is governed by block signals controlled manually.

 

MANUFACTURING FEASIBILITY

The acknowledgment by "Manufacturing" that proposed Engineering part designs and product material specifications will permit volume manufacture consistent with product engineering requirements, and that full consideration has been given to program time in, quality control objectives, available facilities and tooling, and the use of proven manufacturing techniques, methods and processes.

 

MARKED CAPACITY

The carrying capacity of a car as marked or stenciled on the car.

 

MARKER

Front and rear signals of a train (flags or lamps) .

 

MARKER LIGHTS

Also called clearance or running lights.  See clearance lights.

 

MARKS

Letters, numbers, and or characters placed on a package for purposes of identification. Memorandum bill of lading,  A duplicate copy of a bill of lading.

 

MASH WELD

Type of butt weld similar to "Foil Weld" except that the panels overlap slightly and no foil is used.

 

MASS

(m): The ability of an object  to resist a change of vector velocity  when acted upon by external forces.  The ability of an object to exert an attractive force upon another object.  Weight divided by gravity

 

MATCH CHECK

Checking of the fit-up of detail parts by loosely assembling body-in-white components in a balloon  checking fixture.

 

MATCH-MERGE

A direct, mechanical releasing of current model year components into a "carry-over", forward year model.

 

MATS

(Material and Toxicology System). Documents the Materials Engineering approval and toxicology clearance of materials. (Ford derived)

 

MAXIMUM BRAKE HORSEPOWER

Maximum brake horsepower is the maximum power output of an engine.  It occurs at a particular running speed and throttle setting.

 

MAXIMUM ENGAGEMENT

Greatest penetration of one body, such as a vehicle, by another during a collision; instant of greatest force between colliding objects; time and place of this occurrence; position of bodies with respect to each other at this instant.

 

MAXIMUM LOAD

Maximum load is the maximum payload weight which may be loaded onto a vehicle (a truck or trailer)   It does not include the unladen weight of the vehicle

 

MAXIMUM LOAD RATING

(tire)  Maximum load rating is the load rating to the maximum permissible inflation pressure for that tire

 

MAXIMUM LOADED VEHICLE WEIGHT

Maximum loaded vehicle weight is the sum of the unladen weight and the maximum load.  (A) Curb weight;  (B) Accessory weight;  © Vehicle empty weight  and;  (D) Production options weight

 

MBD

(Major Build Document) Step by Step process definition.

 

MCPHERSON SUSPENSION

The McPherson suspension is a type of automotive suspension that utilizes only a single control arm and a single ball joint   The spring in this type of suspension is compressed between the lower control arm and an attachment to the frame or body of the vehicle

 

MEAN DECELERATION

A second parameter important in describing the severity of a crash is the mean or average deceleration of the undeformed section of the car.  A car may crash into a concrete barrier or into a utility pole at 30 M.P.H.  In each case the Delta V is the same.  But in hitting the barrier the car may crush 2 feet giving an average deceleration of 15 g's.  In hitting the pole it may crush 4 feet, giving an average deceleration of 7.5 g's.

 

MEAT RACK (refrigerated car)

The supports near the ceiling from which meat is suspended.  Also called beef rail.

 

MECHANICAL

A vehicle which includes a chassis intended for a specific program release. Unless otherwise specified, the chassis will carry the intended engine and driveline components for the same intended program. Body and sheet metal may be of current production nature, modified only to the extent necessary to adapt to that chassis. The dash panel and floor pan will be as intended for the specific program release unless otherwise specified. (Normally 19 months prior to Job #1.)

 

MECHANICAL EFFICIENCY

The ratio between the brake horsepower and the indicated or total horsepower.

 

MECHANICAL REFRIGERATOR

A car equipped with a diesel powered refrigerating unit under thermostatic control.

 

MECHANICS

The analysis of the action of forces on matter or material systems.

 

MECHANICS START

A feature of the ignition interlock system which enables starting of the vehicle regardless of belt conditions if no one is sitting in any front seating position.

 

MEDIAN

The portion of a highway separating the roadways for traffic in opposite directions.  If the median is more than about 100 feet (30m), the area is usually considered as roadside.

 

MEDIUM SPEED

Not exceeding 30 miles per hour.

 

MEDIUM TRUCK

Any single unit truck with a GVW between 10,000 and 26,000 pounds.

 

MERCHANDISE CAR

A car containing several less-than-car load shipments.

 

METAL DRAFT

(Plate) A pointed metal sheet, usually aluminum, on which layouts are drawn for accuracy.

 

METAL SCRAPES

Caused by sheet body metal or other body parts being dragged across the surface with little pressure

 

METAL SCRATCHES

Caused by sheet body metal or other body metal being dragged lightly over the surface area.

 

METAL TO METAL POSITION

(compression)  The point of maximum compression travel limited by interference of substantially rigid members.

 

METAL TO METAL POSITION

(rebound)  The point of maximum rebound travel limited by interference of substantially rigid members.

 

MEXICAN OVERDRIVE

Kicking vehicle out of gear on downgrade.

 

MIDDLE ORDINATE

 (mo): The perpendicular distance from the mid-point of a chord to the circumference.

 

MIG WELDING

Metal insert gas arc welding where the consumable electrode provides the filler and the weldment is shielded from contamination  by a jet of inert gas.

 

MILE

5,280 feet. Also called statute mile, a unit of distance on land in English speaking countries equal to 5280 feet, or 1760 yards.  2. Also called nautical mile, geographical mile, or sea mile, a unit of distance officially fixed in Great Britain at 6080 feet and formally fixed in the US at 6080.2 feet, but now officially replaced in the US by the International nautical mile.  3. Also called international nautical mile or international air mile, a unit of distance in sea and air navigation equal to 1.852 kilometers, or 6076.1033 feet.  4. any of various other units of distance or length at different periods and in different countries.  Cf. Roman mile, Swedish mile.  [ME; OE mil < L milia (passuum) a thousand (paces)]

 

MILEAGE

Distance in miles.

 

MILLING IN TRANSIT

The stopping of grain, lumber, etc, at point located between the points of origin and destination for the purpose of milling.

 

MINI (Slang)

Less than 100-pound shipment.

 

MINI GATE

Partial side frame used as stand-by for automatic front end assembly fixture on underbody automatic line.

 

MINI WELD

Welding two metals less than .035 using light weight weld gun with small electric tips.

 

MINIMUM RATE

The lowest lawful rate that may be charged for transporting a shipment.

 

MIRROR BUTTON

Metal or plastic pad that is bonded to the inside of a windshield/windscreen as the attachment for a rear view mirror.

 

(1) MIS, (3) MIS

1 "Month-in-service" Reports, 3 Months, etc.

 

MIXED TRUCKLOAD

A truckload of different freight articles combined into a single shipment.

 

MOBOT

Trade name for a modularized robot utilizing from one to nine different axes.

 

MODE

Frequently used to refer to the basic divisions of the transportation industry.  The principal modes of transportation are truck, rail, air and water.

 

MODESTY PANEL

Sheet metal below bumpers that conceals chassis members. Also called modesty skirt.

 

MODIFIER

A circumstance that alters an attribute permanently or temporarily.

 

MODULAR ASSEMBLY

Method of body assembly where operations are confined to joining a few large modules rather than individual parts.

 

MOHAWK

Portion of vehicle roof between the two roof ditches.

 

MOISTURE-RELEASE VALVE

A valve in the air line that emits some air each time the brakes of the tractor are applied.  Prevents water and moisture from collecting in the air system.

 

MOLD

The form from which an object receives its form when cast.

 

MOLDING

A strip of material, either sunken or projected and usually decorative.

 

MOMENT OF INERTIA

A measure of the rotational inertia of a body.

 

MOMENTS 

The external moments acting on the vehicle can be summed into one moment vector having the following components:

 

MOMENTUM

Momentum is the product of the mass of a moving object and the velocity of the object   momentum is a vector quantity

 

MOMENTUM, CONSERVATION OF

The principle that when a system of masses is subject only to internal forces that the masses of the system exert on one another the total vector momentum of the system is constant.

 

MONKEY MOTION

Glass drop motion where direction abruptly changes one or more times to clear body structure.

 

MOPED

A motor powered bicycle.

 

MOT

Ministry of Transport (Canadian Safety Agency)

 

MOTIF

Main theme of design or creative arrangement.

 

MOTOR CARRIER ABREV.

AIM

MOTOR CARRIER ABREV.

All

MOTOR CARRIER ABREV.

CR

MOTOR CARRIER ABREV.

CVIS

MOTOR CARRIER ABREV.

DII

MOTOR CARRIER ABREV.

DIM

MOTOR CARRIER ABREV.

DOT

MOTOR CARRIER ABREV.

DRI

MOTOR CARRIER ABREV.

DRM

MOTOR CARRIER ABREV.

EHI

MOTOR CARRIER ABREV.

ESM

MOTOR CARRIER ABREV.

FMCSA

MOTOR CARRIER ABREV.

FMCSR

MOTOR CARRIER ABREV.

HAZMAT

MOTOR CARRIER ABREV.

HMR

MOTOR CARRIER ABREV.

HMRI

MOTOR CARRIER ABREV.

HMRM

MOTOR CARRIER ABREV.

ISS

MOTOR CARRIER ABREV.

ISTEA

MOTOR CARRIER ABREV.

MCMIS

MOTOR CARRIER ABREV.

MCSAP

MOTOR CARRIER ABREV.

MCSIP

MOTOR CARRIER ABREV.

MVM

MOTOR CARRIER ABREV.

NGA

MOTOR CARRIER ABREV.

OOS

MOTOR CARRIER ABREV.

PCAP

MOTOR CARRIER ABREV.

PRISM

MOTOR CARRIER ABREV.

PU

MOTOR CARRIER ABREV.

RAI

MOTOR CARRIER ABREV.

RAR

MOTOR CARRIER ABREV.

RC

MOTOR CARRIER ABREV.

RSPA

MOTOR CARRIER ABREV.

SafeStat

MOTOR CARRIER ABREV.

SEA

MOTOR CARRIER ABREV.

SMRI

MOTOR CARRIER ABREV.

SMRM

MOTOR CARRIER ABREV.

VII

MOTOR CARRIER ABREV.

VIM

MOTOR CARRIER ABREV.

VMT

MOTOR CARRIER ABREV.

VRI

MOTOR CARRIER ABREV.

VRM

MOTOR CARRIER ABREV.

W1

 

MOTOR VEHICLE

Any vehicle, self-propelled or drawn by mechanical power, designed for operation on the highways or natural terrain in the transport ion of property or passengers.

 

MOTOR VEHICLE ACCIDENT

An accident involving a motor vehicle in transport, but not involving aircraft or watercraft.

 

MOTOR VEHICLE IN TRANSPORT

A motor vehicle on a roadway or in motion within a trafficway.

 

MOTORCYCLE

A two or three wheeled motor vehicle designed to transport one or two persons, so positioned to straddle a seat.

 

MOTOR-VEHICLE TRAFFIC ACCIDENT

Any motor vehicle accident that occurs on a trafficway or that occurs after the motor vehicle runs off the roadway but before events are stabilized.

 

MOUSE

A "T" shaped marking tool used by clay modelers. One end is beveled and pointed; the other end fits into a two-to-four-foot wooden handle.

 

MPH

(miles per hour) English unit of velocity.

 

MRD

Material Required Date

 

MS

(Material Standards) See (ES-M)

 

MTS

(Master Timing Schedule) Chrysler corporate-wide timing schedule for major events leading up to production.

 

MUCKET

Term used for sealing front door to front body hinge pillar; tailgate and glass to body back opening pillar.

 

MUFFLER

Expansion chamber used to muffle the noise of combustion.

 

MULTI UNIT ACCIDENT

A traffic accident in which more than two traffic units are involved in a collision, one with another, but before there is a stabilized accident situation.

 

MULTI-PIECE RIM

A rim consisting of more than one part. Usually two pieces (rim base and side ring), or three pieces (rim base, side ring and lock ring.)

 

MULTIPLE FLASH

Two or more photo flashes made in sequence from different positions to increase the illuminated field in a night photograph.  The camera lens may be covered or the shutter closed in-between flashes. Commonly called "Painting with light".

 

MULTI-STOP BODY

Fully enclosed truck body with driver's compartment designed for quick, easy entrance and exit.

 

MUTUAL CRUSH

The total amount of crush distance shared between two vehicles in a collision.  For example, in an interstate collision the front of one car strikes the side of another.  The front of the striking car crushes one foot and the side of the struck car crushes two feet.  The mutual crush is then three feet so that the undeformed parts of each car have their velocity changes over a distance of three feet.

 

MVMA

Motor Vehicle Manufacturers  Association

 

MVSS

(Motor Vehicle Safety Standard) US Government standard regulating the safety requirements to which all vehicles sold in the U.S. must comply.

 

MY

Model Year

 

MYTD

Model Year-To-Date

References

Detroit Diesel

Caterpillar User's Manual