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20112011DOMESTICSDOMESTICS

BY PAUL WEISSLERBY PAUL WEISSLER

Ford Fiesta

Ford Mustang

Ford F-Series Super Duty

TECH OVERVIEW OF THE

The 2011 model year gives us Chrysler’s first new entrysince the trials of 2009; it’s the Jeep Grand Cherokee,and it’s been worth waiting for. The first of the Fiats—

the 500 Sport—and a new Wrangler are coming very shortly.Ford just doesn’t stop rolling out new products either, with fourmajor additions—the Fiesta economy car, the Ford F-Series

25November 2010

It’s been said that this country’s economic recovery(and future prosperity) are directly connected to thehealth of its auto industry. Based on the quantity ofnew model introductions, things may be looking up.

Ford Explorer

Chevy Cruze

Chevy Silverado

Fiat 500 Sport

Jeep Wrangler

Super Duty and Mustang, each with twonew engines, and an all-new Explorer.And General Motors has two significantnew entries out already—the ChevyCruze and Buick Regal—plus the up-graded Chevy Silverado/GMC Sierra.The much-anticipated Chevy Volt plug-in electric will be out shortly as well.

One of the most significant overall ser-vice developments is the increasing in-dustrywide use of computer algorithmsto determine and post oil change servicerecommendations on the instrumentpanel display. For the 2011 model year,Ford is across the board with an owner’smanual statement that the interval couldbe as high as 10,000 miles or one year.

So let’s see what the domestic au-tomakers have been up to. Most ofthese vehicles will be on the road in afew months, and some of them will bepulling into (or towed into) your servicebays eventually.

ChryslerFor those who thought Chrysler was adead duck, the Jeep Grand Cherokeeis evidence this company can put to-gether a new model that we have tocheer, on-road or off. Perhaps you’veheard that it’s really a Mercedes M-Class under the skin. Sure, the two ve-

TECH OVERVIEW OF THE 2011 DOMESTICS

The Pentastar 3.6L V6 is Chrysler’s new engine and will first be installed in theJeep Cherokee. It will soon go in the Chrysler 200 (which replaces the Sebring)and likely all other V6-equipped vehicles as production ramps up.

The illustration on the left shows the belt routing for Chrysler’s 3.6L V6 with the power steering pump: 1. idler pulley; 2.water pump; 3. power steering pump; 4. belt; 5. a/c compressor; 6. crankshaft pulley; 7. tensioner; 8. alternator. The illus-tration on the right shows the belt routing for the 3.6 V6 when an electrohydraulic power steering pump is used: 1. alter-nator; 2. idler pulley; 3. belt; 4. a/c compressor; 5. water pump; 6. crankshaft pulley; 7. tensioner.

26 November 2010

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hicles were developed at the same timewhen Chrysler was under Mercedes-Benz ownership, but aside from the ba-sic platform and some general sheetmetal shaping that it dictated, it’s aChrysler product. The engine is abrand-new 3.6L V6, made in Trenton,MI, and it’s pure Chrysler engineering.

The engine, all-aluminum with steelcylinder liners, is a 60° V6, rated at 290hp and 260 ft.-lbs. of torque, and it’s thebase engine for the vehicle. Called thePentastar, its firing order of 1-2-3-4-5-6is based on numbering the left bank(driver’s side) 2-4-6 and the passenger’sside 1-3-5. The 290 hp is produced at6400 rpm, the peak torque at 4800 rpm.But the torque curve is pretty flat, sothat over 90% is available from fast idle(1600 rpm) on.

The dual-overhead camshafts arechain-driven and there are cam phasersfor variable valve timing on both the in-take and exhaust camshafts. The valvetrain uses rockers, with the hydrauliclifters underneath them. The oil filter is“Euro-enviro”—that is, a cartridge fil-ter—and is located near the top frontof the engine.

The Pentastar has a serpentine beltthat you have to route carefully to avoidhaving the water pump (driven off theback of the belt) run backward. Some-time during the model year, Chryslerwill be dropping the belt-driven powersteering pump and switching to an elec-trohydraulic pump that will be mountedaway from the accessory belt drive. Thatwill call for a new belt routing.

Like all other engines installed inChrysler vehicles (including the 4-cylinder it sources from Hyundai),there’s no mass airflow (MAF) sensor.No real surprise, because Chrysler isthe only domestic company, and proba-bly one of only a handful worldwide,that has never used one. There’s only amanifold absolute pressure (MAP) sen-sor (up against the firewall on the rightside of the engine compartment); witha well-developed computer algorithm,that’s all Chrysler needs. It requiresmore computer modeling of engines,and more work developing the emis-sions control software, but it does meanyou don’t have to test for a defectiveMAF sensor.

TECH OVERVIEW OF THE 2011 DOMESTICS

Although the 1.4L turbo is the optional engine for the Chevy Cruze, it’s expectedto account for 70% of sales. The front cooling module has a computer-controlled

air flap to improve the coefficient of drag, for better highway fuel economy.

A Z-link with torsion beam isused in the Cruze rear suspension.

28 November 2010

This diagram shows the “air” suspension onthe Jeep Grand Cherokee: 1. nitrogen res ervoir; 2. electronic controlmodule; 3. front strut; 4. compressor/valve block assembly; 5. frontheight sensor; 6. nitrogen lines; 7. rear “air” spring; 8. rear height sensor.

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The 5.7L Hemi V8 with “multipledisplacement” (cylinder deactivation) isthe optional engine, and five-speed au-tomatics are the transmission choices.

The four-wheel-drive systems arepure Jeep, and should be familiar: theall-wheel-drive Quadra-Trac I, the go-almost-anywhere Quadra-Trac II (two-speed transfer case and instantaneoustorque transfer to the appropriate axle)and the Quadra-Drive II, which adds arear electronic limited-slip differentialto Quadra-Trac II.

With Q-T II or Q-D II, the GrandCherokee will have a new optional “air”suspension with a terrain-select switch,an idea pioneered on the English LandRover line. Terrain-select adjusts throt-tle, braking, transmission shifting, hillstart assist and hill descent control withground clearance from the air suspen-sion. The driver can pick from coordi-nated settings for sand/mud, snow, rock-climbing, sport (on-road handling) andautomatic response.

The “air” suspension is not quitewhat it seems. First, it’s filled (up to220 psi) with pure nitrogen, not air,and operates in a closed loop from areservoir. There’s a compressor, but it’sstrictly for service situations, such asfollowing the installation of new parts.

If any nitrogen-filled component isto be replaced, it first must be deflatedusing a scan tool with appropriate soft-ware. The compressor is a small unit,strictly for a one-component refill, andusing pure nitrogen from a servicetank. The filtered-hose assembly foradding nitrogen to the reservoir is lo-cated behind the rear seat.

If you put the vehicle on a lift orjack it up at any corner, the air suspen-sion disables. If you’re doing a wheelalignment, select “Sport” mode first onthe suspension menu; if you’re using ascan tool, select the “Aero” mode.

The Fiat 500 Sport econocar isdue to reach dealerships before theend of the year, if it’s not there al-ready. It will be powered by a 1.4Lnaturally aspirated 4-cylinder withMulti-Air, the Fiat system that in-cludes intake valve throttling insteadof a throttle plate, and, like Chrysler,speed density fuel calibration insteadof mass airflow sensing.

Right: A twin-clutchassembly, engaged bymotors, executes the

shifts in the Ford Fies-ta’s dual-shift gearbox.

Below: The Fiesta’s1.6L engine has a“stretchy” belt—a ser-pentine belt with no ten-sioner. The car has elec-tric power steering, butthe belt still must wraparound the a/c com-pressor, alternator andwater pump, in additionto the crankshaft pulley.

29November 2010

Although most Mustangs get the 3.7L V6, the new 5.0 V8 shown hereis the engine that gives the car its performance image. Notice the

bar that connects the strut towers, for improved handling.

The Chrysler Sebring is being re styledand gets a new name—Chrysler 200. Itwill use the 2.4L 4-cylinder as the baseengine and the new 3.6L Pentastar as anoption. The 300 also gets a makeover,but no details have surfaced yet.

General MotorsThe Chevy Volt is getting all the publici-ty, but the technical details still were notavailable as this issue of MOTOR was be-ing readied for print. However, theChevy Cruze is the vehicle GM is

counting on for significant sales. We’dcall it all-new, but it’s been on sale in 60other countries for about two years, anddoing pretty well (about a quarter-mil-lion sold). The Cruze is a Corolla/Civic-size front-drive.

The engine choices are a 1.4L turbo -charged Four that produces 138 hp and125 ft.-lbs. of torque and a 1.8L naturallyaspirated Four (the base engine) that de-velops 136 ponies. It would hardly seemworthwhile paying for the extra complex-ity and cost of a turbo, but the 1.4 devel-ops 148 ft.-lbs. of torque at 1850 rpm, anice low number for a turbo. The 1.8produces just 123 ft.-lbs. but not until3800 rpm. Furthermore, the highway fueleconomy numbers of the 1.4 are likely tobe significantly better, although as ofnow, the only model with a number is aspecial “Eco” 1.4 with six–speed manual,rated at 40 mpg. So the buyer is gettingboth performance and fuel economy.

A surprising aspect of both engines isthat the blocks are cast-iron. But the 1.4is a hollow-frame design that savesabout 20% in weight over a convention-al cast-iron structure. The cylinderheads are aluminum. Both engines havecartridge oil filters.

The 1.4 turbo “Eco” model is aidedby a powertrain computer-controlled,motor-actuated air flap in the front cool-ing module. It’s open until 38 mph forcooling airflow, then closes to improveaerodynamics and does not reopen untilroad speed drops to 34 mph. The caralso has a full underbody pan for aero-dynamic improvement, so there’s an is-sue for service access.

A fuel-saving feature called NeutralIdle shifts the electronically controlledsix-speed automatic into Neutral whenthe car is stopped with the brakes ap-plied. It shifts back into Drive when thepedal is released. Motorists are likely tonotice the slight rollback on a hill.

The most significant service aspect isthat the Chevy Cruze—as well as theother newbie, the Buick Regal—has theglobal electrical architecture introducedon the Camaro and other 2010 GMmodels. This system, which also re-quires the new MDI scan tool for fulldiagnostics, among other things, doesnot permit test-swapping of electronic

TECH OVERVIEW OF THE 2011 DOMESTICS

30 November 2010

Circle #16

Circle #17

Circle #18

Circle #19

modules. Each has specific VIN data,there’s no learn function and even atemporary swap will introduce all kindsof problems, including nearly-impossi-ble-to-erase trouble codes.

All Cruze models get rack-mountedelectric power steering, which producesa more precise response than the col-umn-mount type. According to Chevyengineering, it’s worth about .5 mpg onthe window sticker.

The spare tire is an option on this car,so if you go out on a road service call fora flat, ask first, or be prepared to find aninflator kit. The front suspension is Mac -Pher son struts, and the rear is a torsionbeam with a Watts linkage (Z-shapedlink setup). It goes along with a stiff bodystructure and generous use of hydraulicsuspension bushings to soften the ride.

The front-drive 2011 Buick Regal isa badge job. The car actually is an OpelInsignia sports sedan. It’s a midsizesedan with the 2.4 Ecotec direct-injec-tion Four, rated at 182 hp/172 ft.-lbs. oftorque, and will carry a 30-mpg highwayfuel economy rating. The performanceengine is a turbo, the 2.0 Four, rated at220 hp/258 ft.-lbs. of torque, and 29mpg highway; there’s no V6. Both en-gines are all-aluminum, with variablevalve timing on intake and exhaust.

This model also has MacPhersonstruts in front, but a multilink rear sus-pension and an optional driver-selec-table electronic damping control withthe turbo. The transmission is the six-speed automatic, with a six-speed man-ual coming shortly.

The Chevy Silverado/GMC Sierraheavy-duty trucks get an upgraded Du-raMax 6.6L diesel (rated at 397 hp/765ft.-lbs. of torque) to meet the new emis-sions regs, which means they have theurea solution tank. GM vans get theDuraMax as well. If the 5.3-gal. tank isempty, the vehicles are limited to 55mph, and to 4 mph on a restart. TheDuraMax is rated for B20 biodiesel.

The engine has a single turbo, but it’sa variable-nozzle type and a computersoftware algorithm enables it to closedown for exhaust braking. This systemisn’t quite as effective as the flap typeused by the competition, but doesn’tcost much to produce.

There’s a new DuraMax thermostatwith multiple air bleed holes. If youhave to replace it, be sure to installthe new one with the bleed holes fac-ing the front of the engine. The air in-take on vans has an oval air filter, the

pickups the conventional flat panel.If you have to service the front

cooling module, note that the chargeair cooler duct connections are madewith plastic rings. Handle with careto avoid breaking them.

31November 2010

Circle #20

GM has a 2011 engine oil spec forall models, in a classification systemcalled Dexos, and it’s designed to workin combination with an enhanced oilchange algorithm in the powertraincomputer. The idea is to be able to ex-tend oil change intervals where feasible.If the engine oil that meets the Dexosspec for a particular engine isn’t avail-able, there are acceptable substitutions.The 5W-30 with the American Petrole-um Institute’s “starburst” symbol is al-lowed for all naturally aspirated enginesexcept the Camaro/Corvette/CadillacCTS with the small-block Corvette en-gine. For those engines, a super-premi-um synthetic (such as Mobil1) is per-mitted. The super-premium syntheticalso is acceptable for the turbos.

FordThe Big Blue Oval just keeps rollingout the new models, with an emphasison improving fuel economy. That in-

cludes V6s in place of V8s and turboFours in place of V6s. Perhaps themost dramatic example is moving thelegendary Explorer off the truck frameplatform onto the crossover platformalso used by the Flex.

The new Fiesta, engineered in Eu-rope but made in Mexico for the U.S.market, is a 40-mpg model with a six-speed automatic transmission. This isno ordinary automatic, but rather adual-clutch transmission, also called adual-shift gearbox (so you’ll see suchacronyms as DCT or DSG). Namedthe PowerShift by Ford, it’s a premiumdesign also used on some VW and Au-di models, plus many racing cars. It’slike two automated manual transmis-sions in one, with a twin-clutch assem-bly in place of a torque converter. Thegear changes are made by engagingone clutch while disengaging the other,so it’s instantaneous and smooth and,as a variation on a manual transmis-

TECH OVERVIEW OF THE 2011 DOMESTICS

32 November 2010

Circle #21

A knob on the Explorer’s console con-trols computer coordination of throt-tle, transmission shifting, hill descentand stability control according toroad conditions. From the top coun-terclockwise, the icons are for snow,sand, mud and normal driving.

sion, more fuel-efficient. The transmis-sion has a fluid-fill-for-life, not surpris-ing for this type, because the gearboxinternals are similar to a manual’s. Afive-speed manual is the base gearbox.

The engine is an all-aluminum de-sign (including the oil pan) 1.6L dual-overhead cam with variable intakeand exhaust timing, which develops119 hp and 109 ft.-lbs. of torque, ade-quate for the size and weight. Themost noticeable underhood feature isthat there’s no belt tensioner; it’s a“stretchy” belt, but for the first time,this one covers three accessories—thea/c compressor, alternator and waterpump. The replacement procedureinvolves cutting off the old belt andinstalling the new one using a hard-ware kit included with it.

Column-mounted electric powersteering is used, with a computer algo-rithm called Pull-Drift Compensation,to make it easier to keep the car track-ing straight even on crowned roads orin crosswinds. It also can correct forminor amounts of wheel imbalance.This was introduced last year on theExplorer. The Fiesta has discs in front,drums in the rear, and a simple torsionbeam rear axle.

The 2011 Mustang gets a substantialmakeover, with a brand-new 5.0L (302-cube) V8 heading the list of changes.The engine is all-aluminum, with fourvalves per cylinder operated by thedual-overhead camshafts with intakeand exhaust cam phasers for variablevalve timing. At a time when fuel econ-omy is getting increased emphasis, itmay seem surprising that Ford wouldinvest in a V8 when it already has themodular V8. The answer is that a new,more efficient V8 was needed to appealto a significant segment of the Mustangworld, even though it may not be an ul-tra-high-volume engine. Ford designedan all-new engine that had the samebore centers as the modular engines soit could be built on the same assemblyline. That was a huge cost saving, andthere’s no doubt that the 5.0/302 enginedisplacement has a historic ring to FordV8 enthusiasts.

This engine develops 412 hp at 7000rpm (390 ft.-lbs. of torque). It develops

credible fuel economy numbers, too—18 city/25 highway with the six-speedautomatic, 17/26 with the six-speedmanual. And for those who want bettermileage, there’s the 3.7L V6, which notonly develops 305 hp at 280 ft.-lbs. of

torque, but also delivers 31 mpg high-way (19 city). Additionally, there’s anaturally aspirated “Boss” version ofthe 5.0 that adds 28 more horses (at ascreaming 7500 rpm), listed as a 2012model.

33November 2010

The 5.0 V8’s firing order is 1-5-4-8-6-3-7-2, and cylinder numbering is Ford’susual 1-2-3-4 on the right-side bank, 5-6-7-8 on the left (driver’s side). The oilfilter is a conventional spin-on type.

All new Mustangs have column-

mounted electric power steering withthe pull-drift compensating algorithm.

Will the public take to the new Ex-plorer, built on a crossover platform,with transverse front-drive powertrain,no V8 and maximum tow capacity at

5000 lbs? Ford certainly thinks so, andfor those who really want fuel econo-my, the 3.5 turbo V6 (290 hp/255 ft.-lbs. of torque) can be exchanged for a2.0L direct-injection turbo Four,which develops 237/250 but with towcapacity dropping to 2000 lbs. V6 fueleconomy is 17/25; the 2.0 Four is ex-pected to come in at 28 to 29 mpghighway.

One appealing new feature is a sim-plified version of turn-a-knob terrainselection, in this case operating with-out air suspension but with AWD. Itintegrates throttle, stability control, hilldescent management and transmissionshifting for four modes: snow, sand,mud and normal driving. In addition,there’s “curve control,” which is an al-gorithm that reduces engine torqueand applies the antilock brakes to slowthe vehicle by up to 10 mph if it entersa curve too fast. It’s based on steeringangle vs. how fast the vehicle is turn-ing, so it basically functions as an en-hancement to stability control.

Like other Ford products on thecrossover platform, the Explorer hascolumn-mounted electric power steer-ing and a six-speed automatic.

The F-Series Super Duty is surelythe most technically new model in theFord lineup. Not only does it featurethe first Ford-engineered big diesel—a6.7L Powerstroke V8, to replace thelong-used series of Navistar designs—but it also has a brand-new 6.2L gaso-line V8. That engine also will be usedin other Ford trucks, with the high-performance F-150 SVT Raptor thefirst to get it.

The 6.2 is a two-valve, single-over-head cam V8 with two spark plugs percylinder. The primary is coil-on-plug(C-O-P) ignition, and there’s a sparkplug wire from that ignition unit to thesecond plug. Cylinder numbers are thesame as on the other V8s, and the fir-ing order is 1-5-4-8-6-3-7-2.

The engine has variable cam timing,and in case there’s ever an issue withcam phaser operation, check for aplugged oil filter in the unit. The rock-er arms hold the hydraulic lifters.

The 6.7 diesel, rated at 390 hp/735ft.-lbs. of torque, is extremely sophisti-

TECH OVERVIEW OF THE 2011 DOMESTICS

34 November 2010

Circle #23

cated. First, it features an outboard in-take system and an exhaust over the V,a more compact layout that also is qui-

eter. Like others, it’s a four-valve with asingle in-block camshaft, but with aseparate pushrod and rocker arm for

THE 2011 DOMESTICS

The new 6.2L V8 for Ford trucks is atwo-valve, single-overhead-camdesign with two plugs per cylinder.One plug is fired by a coil-on-plug(C-O-P) setup; the other is con-nected by a conventional high-voltage plug wire from the C-O-P.

If a performance issue on the 6.2L V8 is traced to the camphaser, note that the filter is replaceable.

36 November 2010

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each valve. Each pair of valves fits intoa single cam follower with separate hy-draulic lifters. The separate rockers, vs.

the more common use of one double-rocker assembly for two valves, providesmoother operation. The heads are

aluminum, the block is a compactedgraphite iron and the oil pan is plasticwith a quarter-turn plastic drain plug.

The diesel has two separate coolingsystems, each with its own radiator (onea two-stage design), and each with twothermostats and one belt-driven waterpump. One system is a conventionalhigh-temperature circuit, which coolsthe engine and turbo. The other is alow-temperature circuit for the specialcoolers (transmission, EGR, fuel andcharge air).

Although the smaller coolant hoseshave conventional clamps, the largeones use quick-connects that containan internal sealing O-ring and incorpo-rate a retaining wire clip.

The fuel system uses piezoelectricinjectors that pulse up to five times percombustion cycle. If you ever have toreplace an injector, you’ll have to notean injection quantity specification onits label, and program the new injectorto that spec.

Like the competition, the 6.7 dieselrequires urea fluid injection to meetthe new emissions regulations.

The Super-Duty also has a new six-speed automatic (the manual is gone).And like a number of Ford automaticsover the years, it incorporates a Ravi-gneaux gearset, which is a combinationof two planetaries in one compact as-sembly, to provide four speeds. A plan-etary is added and the combination de-livers the six forward speeds.

As we reported in the August 2010issue, Ford has a companywide U.S.coolant changeover underway,switching to an orange dye organicacid technology (OAT) antifreeze,with any GM DexCool formula an ac-ceptable choice. This is the type usedon all Ford of Europe models. Not allFord U.S. cooling systems have beenchanged over yet, with some still us-ing the yellow Zerex G-05 Europeanformula also used by Mercedes or adeep green Mazda Asian formula. Wecovered the subject in great detail inthat issue, which can be seen atwww.motor.com.

TECH OVERVIEW OF THE 2011 DOMESTICS

The Ford-engineeredPowerstroke6.7L enginefeatures twoseparatecoolingsystems, eachwith twothermostats,a specificbelt-drivenwater pumpand a specificradiator.

Unlike other four-valve pushrod diesels, the Ford Powerstroke V8 engine has aseparate pushrod and rocker arm actuating each valve.

37November 2010

This article can be found online atwww.motormagazine.com.