Peterbilt 579 vs Western Star 4900
Below, every figure both makers publish sits side by side, with the Peterbilt 579 and the Western Star 4900 drawn to the same scale from their dimension drawings.
All specifications
Every figure the makers publish. Search for one, or show only those that differ.
Dimensions
Bumper to back of cab (BBC)3.15 m124 in BBC; SBFA3.124 mBBC; SF, SB and XD
Front overhang1.234 mNot published
Front of frame to front axle0.795 mFOFNot published
Front axle to back of cab1.882 mFAX to BOCNot published
Cab height above frame2.052 mFrom bottom of frame railNot published
Cab floor height above frame0.406 mFrom bottom of frame railNot published
Overall width2.388 mTop view, excluding mirrorsNot published
Width over mirrors3.063 mFront viewNot published
Bumper to back of cab (118 in BBC variant)2.997 m579-118 SBFANot published
Front axle to back of cab (118 in BBC variant)1.732 m579-118 SBFA; FAX to BOCNot published
Sleeper roof height above frame (44 in low roof)2.126 mNot published
Sleeper roof height above frame (58 in low roof)2.172 mNot published
Sleeper roof height above frame (58 in high roof)2.586 mNot published
Sleeper roof height above frame (72 in high roof)2.586 mNot published
Sleeper roof height above frame (80 in high roof)2.637 mNot published
Sleeper length (44 in sleeper)0.914 mNot published
Sleeper length (58 in sleeper)1.219 mNot published
Sleeper length (72 in sleeper)1.6 mNot published
Sleeper length (80 in sleeper)1.753 mNot published
Cab-to-sleeper opening height (low roof)1.245 mDimension A, walkthrough openingNot published
Cab-to-sleeper opening width (low roof)1.73 mDimension B, walkthrough openingNot published
Cab-to-sleeper opening height (high roof)1.689 mDimension A, walkthrough openingNot published
Cab-to-sleeper opening width (high roof)1.73 mDimension B, walkthrough openingNot published
Sleeper headroom (80 in UltraLoft)2.438 mNot published
Sleeper storage volume (80 in UltraLoft)1.98 mÂłNot published
Wheelbase (maximum)Not published11.379 mWB; all four versions
Bumper to front axleNot published0.838 mBA; SF set-forward and EX
Station 0 to back of cabNot published3.063 m4900SF 123 BBC
Station 0 to front axle centrelineNot published0.787 m4900SF
Bottom of frame rail to top of cabNot published2.129 mstandard cab
Top of frame to top of cabNot published1.859 m
Frame widthNot published0.864 moutside of frame rails
Fenderette widthNot published2.565 m
Fender-only widthNot published2.426 m
Weight
Front axle capacity6,622 kgNot published
Rear axle capacity20,865 kgNot published
Front axle capacity (minimum option)5,443 kgNot published
Rear axle capacity (minimum option)9,525 kgNot published
Rear tandem axle rating (PACCAR DX-40)18,144 kgTandem GAWRNot published
Max gross combination weight (PACCAR DX-40 axle)36,287 kgAxle GCW limitNot published
Max operating weight (PACCAR MX-13 engine)63,503 kgNot published
Max operating weight (PACCAR MX-11 engine)49,895 kgEngine maximum operating weightNot published
Max gross combination weight (PACCAR TX-12 transmission)49,895 kgStandard TX-12 limitNot published
Max gross combination weight (PACCAR TX-12 PRO transmission)31,751 kgNot published
Max operating weight (PACCAR TX-18 transmission)63,503 kgNot published
Engine dry weight (PACCAR MX-13)1,134 kgNot published
Engine dry weight (PACCAR MX-11)998 kgNot published
Engine
Engine modelPACCAR MX-13, PACCAR MX-11, Cummins X15, Cummins X15N, Cummins ISX12N, Cummins L9NDetroit DD1514.8 L, 455-505 HP, 1,550-1,750 lb-ft
Gross power451 kW (605 hp)Cummins X15, top ratingNot published
Max torque2,779 NmCummins X15, top ratingNot published
Displacement (PACCAR MX-13)12.9 LNot published
Power (PACCAR MX-13)380 kW (510 hp)Not published
Torque (PACCAR MX-13)2,508 NmNot published
Displacement (PACCAR MX-11)10.8 LNot published
Power (PACCAR MX-11)332 kW (445 hp)Not published
Torque (PACCAR MX-11)2,305 NmNot published
Displacement (Cummins X15)15 LNot published
Displacement (Cummins X15N)14.5 LNot published
Power (Cummins X15N)373 kW (500 hp)Maximum rating, up to 500 hpNot published
Torque (Cummins X15N)2,508 NmMaximum rating, up to 1,850 lb-ftNot published
Displacement (Cummins ISX12N)11.9 LNot published
Power (Cummins ISX12N)298 kW (400 hp)Maximum rating, up to 400 hpNot published
Torque (Cummins ISX12N)1,966 NmMaximum rating, up to 1,450 lb-ftNot published
Displacement (Cummins L9N)8.9 LNot published
Power (Cummins L9N)239 kW (320 hp)Single ratingNot published
Torque (Cummins L9N)1,356 NmSingle ratingNot published
Transmission
TransmissionPACCAR TX-12 PRO automated (engines up to 1,000 lb-ft, GCWR up to 70,000 lb)Eaton Fuller FR-13210B 10-, 13-, 15- and 18-speed; Eaton Fuller UltraShift PLUS; Allison 4000, 4500, 4700 automatic
Sleeper options44 in to 80 in; 80 in UltraLoftNot published
Transmission (PACCAR TX-12)12-speed automated, on-highway fuel efficiency; 2 reverse; max engine 510 hp / 1,850 lb-ft; max GCWR 110,000 lb; system weight 657 lb (298 kg)Not published
Transmission (PACCAR TX-12 PRO)12-speed automated, extreme-duty clutch; max engine 455 hp / 1,700 lb-ft; max GCWR 70,000 lb; system weight 665 lb (302 kg)Not published
Transmission (PACCAR TX-18)18-speed automated, vocational / heavy haul; max engine 510 hp / 1,850 lb-ft; max operating weight 140,000 lb; system weight 808 lb (367 kg)Not published
Transmission (Endurant HD)12-speed automated, on-highway fuel efficiencyNot published
Transmission (Endurant XD)18-speed automated, vocational, heavy haul, high performanceNot published
Transmission (Eaton FR/RT)Manual; 9, 10, 11, 13, 15 or 18 speedsNot published
Transmission (Eaton UltraShift PLUS)Automated; 10, 11, 13 or 18 speedsNot published
Drive axle ratio range (PACCAR DX-40)2.47 to 3.70; 1,650 lb-ft straight torque rating, 1,850 lb-ft multi-torque ratingNot published
Front axleNot publishedsingle 12,000-23,000 lb (Detroit, Hendrickson AIRTEK, Meritor); Meritor tandem 40,000 lb and front drive 22,000-23,000 lb with set-back axle only
Rear axleNot publishedtandem 40,000-70,000 lb; tridem 69,000-105,600 lb; single 23,000-30,000 lb (Detroit, Meritor, Sisu)
Capacities
Fuel tank568 Laluminium 25 in cylindrical 60-150 gal (227-567 L); 23 in cylindrical 50-150 gal (189-567 L)
Fuel tank (smallest option)151 LNot published
Fuel tank diameters20 in, 23 in or 26 inNot published
DEF tank (small)38.6 LNot published
DEF tank (medium)60.9 LNot published
DEF tank (large)76.1 LNot published
DEF tank (medium aero)52.6 LNot published
DEF tank (large aero)67.8 LNot published
Service intervals
Engine oil and filter120,000 kmNot published
Fifth wheel24,000 kmor monthly: inspect, greaseNot published
Axle and gearbox first-fill oilfirst change at 3,000-5,000 mi (4,800-8,000 km); level check every 15,000 mi (24,000 km)Not published
Service capacities
DEF tankNot published6, 13 and 23 gal (23, 49 and 87 L)
Sources: Peterbilt 2024 Heavy Duty Body Builder Manual, Rev A (May 2024), Figure 3-4 Model 579-124 SBFA overall dimensions · Western Star 4900 tech sheet WS/MC-DT-531 (2018, copy on xr793.com)
Drawn to scale
Side views measured off each maker's dimension drawing, front edges and ground lined up.
Peterbilt 579 vs Western Star 4900: questions
Where do these figures come from?
Each model's own published spec sheet or brochure, linked under the table. Builds differ by market and year, so confirm the figures for a particular machine with its dealer.
Can I rent or buy these machines in the UAE?
Each model's page lists the ones for hire and for sale on EquipmentsFinder now, with typical prices in AED.
