Originator: Stephen I. Dains/sdains
Page 4
Date Issued: 2-16-04
guidebookcommon spring 2004.doc
DateRevised: 5/6/2004
D0310
Beforeproduction is startedonanewproduct, thebuilder should conduct a thorough sign-off of
any significant change toa vehiclemodel's structureorOEM chassis change. All system
functions shouldbe verifiedand completed vehicledriveevaluations conducted. Noise, Vibration
andHarshness (NVH), ride, handling, braking, fuel fill, etc. characteristics shouldbe formally
evaluatedbymanagement personnel under typical operationand load conditions toassure
customer satisfactionwith the completedproduct.
D0311
Vehiclebody design can significantly impact the timeandeffort (i.e., cost) of chassis service.
OEM chassis serviceability shouldbe reviewedduring the vehicledesignprocess. Chassis
systemswhich shouldnot beobstructedby added components include: fluid fills, fluid level
checks, fluiddrains, filters, wheels, suspension, driveline, fuel tank andE-Series engine cover. If
any chassis components areobstructedby added components, access instructions shouldbe
provided in servicemanuals.
D0312
FordTechnical ServiceBulletins areavailable to keepbuilders apprisedof corrections toFord
product issues. Thesemay bepurchaseddirectly fromHelm Inc., listed inAppendixXIII. They
arealsoavailableon thewebat
. Under theMaintenanceTab, Click
Recalls/ServiceBulletins. Requires login.
D0400 PROCESSCONTROL
As an initial part of introducinga vehicleor chassis intoproduction, theremust beaprocess in
place toassure the chassis beingused is appropriate for the intendeduse. All toooften, Ford
engineering is requested toapproveor assist in upgradinga chassis because it doesn'tmeet the
customer's needs (generally due to inadequateGAWR, GVWR, or option content). Because this
process is at best difficult, time consuming, andopen for error, and is often impossible, Ford
engineering canno longer support reworkinga vehicle or chassiswhich is not appropriate for the
intendeduse.
ProcessControl, an integral part of theQualityPlan, serves tominimize variationand reduce the
cost of achieving consistency. If units arebeingbuilt in inconsistent ways (i.e., hose routings, wire
routings, different nuts/bolts) it is difficult to conduct problemanalyses andachievequality. You
can introduce consistency into themanufacturingprocess through thedevelopment of effective
process control measures -- each vehiclebuilt with the samebill-of-materialswill be virtually
identical. It is important to recognize that process control, in itself, does not guaranteequality.
Theproductionof a consistent product displays goodprocess control, even though theproduct
may beof consistently poor quality!
All parts and functionswithinanymanufacturingprocess require some level of control. Since it is
impractical and costly to control all aspects of theprocess, a few key elements are tobe chosen.
Thekey todevelopingprocesscontrol is to identify thoseelementswithinyour
manufacturingprocesswhichcanhaveasignificant anddirect impact onC/FMVSS, safety,
quality, durability, functional performanceor customer satisfaction.
Theseare the
critical
elementswithin yourmanufacturingprocess. Some examples of critical elements areas follows:
•
Critical Dimensions
: Apartmay havea critical dimension that will causeaquality problem if
it is notmaintained.
•
Critical Parts
: Amanufacturedor purchasedpartmay bea critical part if the specificationof
that part is important tomeet safety performanceobjectives or Ford recommendations (i.e., a
grade5bolt versus agrade2bolt).
•
Critical Assemblies
: Anassemblymay bea critical assembly if it is critical tomeeting
C/FMVSS requirements. This includes assemblies purchased from suppliers.
•
Critical Processes
: Anassembly processmay bea critical process if varying theprocess
can result inadifferent andundesirable result (i.e., drillingholes or installing fasteners near
fuel systems or electrical components, hoseandwire routings).
•
Critical Torques:
Critical torques are tobe controlled toassure that parts areput together
properly andwill functionproperly for theuseful lifeof the vehicle.
A special symbol is oftenused to identify critical elements onengineeringdrawings, assembly
