PI / CHU and legacy CXU
The manual distinguishes axle-forward CHU and axle-back CXU designations. Its illustrated bumper boundary yields 117.3 in BBC for these examples.
Mack body-builder Section 0 · November 2021 ↗
THE TRACTOR REFERENCE DESK
Mack
Pinnacle family
A legacy Mack highway/regional and vocational tractor family.
01 / FIND YOUR REFERENCE
Choose a reference edition
Start with the model configuration, then choose a publication and explore its documented equipment.
Catalogue reference
Selecting equipment records your research choice. It does not calculate dimensions, establish an available combination or rate a truck.
About this edition & its evidence
Mack PI / CHU613 axle-forward drawing · November 2021 · page 64. The manual identifies CHU as axle-forward Pinnacle and CXU as an earlier Pinnacle designation. The illustrated dimension boundary and front bumper control these values; a marketed BBC or another bumper may differ.
Mack PI / CHU613 axle-forward drawing · November 2021 · page 64 ↗
DIMENSION GUIDE / A–H
Precision visual reference
Select a measurement to highlight its endpoints and see what the chosen publication confirms.
Mack Pinnacle · PI / CHU613 axle-forward · November 2021 · dimensioned day-cab drawing · 2 published / 6 to verify
Published value Needs verificationSchematic · not to scale
A / SIDE VIEW
Bumper to back of cab (BBC)
Front bumper to the back of the driving cab. Excludes an additional sleeper; it is not overall tractor length.
117.3 in2,979 mm
Published for this reference; confirm the individual build.
Original illustrative views; not to scale, a certified drawing or a selected-build rendering. Endpoints explain the measurements. Published values come from the cited reference, never from the image.
Selected reference: Mack PI / CHU613 axle-forward drawing · November 2021 · page 64. Published values remain tied to this edition.
View the complete dimension table ↓02 / THE MEASUREMENTS
Published dimensions
PI / CHU613 axle-forward · November 2021 · dimensioned day-cab drawing
| Measurement | Reference value | Scope / how to verify |
|---|---|---|
| Bumper to back of cab (BBC) | 117.3 in2,979 mm | Published in the selected manufacturer reference.Mack PI / CHU613 axle-forward drawing · November 2021 · page 64 ↗ |
| Bumper to front axle (BA) | 29.8 in757 mm | Published in the selected manufacturer reference.Mack PI / CHU613 axle-forward drawing · November 2021 · page 64 ↗ |
6 dimensions still to verify · build record / measurement
| Measurement | Reference value | Scope / how to verify |
|---|---|---|
| Wheelbase | Not verified | Build record / measurement required. |
| Overall tractor length | Not verified | Build record / measurement required. |
| Overall height | Not verified | The drawing gives 112.5 in (2,857.5 mm) to the cab roof, below the exhaust. It does not establish overall height.Mack PI / CHU613 axle-forward drawing · November 2021 · page 64 ↗ |
| Cab / body exterior width | Not verified | The 94.9 in rear tyre envelope in this drawing is not a verified maximum body or mirror width.Mack PI / CHU613 axle-forward drawing · November 2021 · page 64 ↗ |
| Width across mirrors | Not verified | Build record / measurement required. |
| Fifth-wheel height | Not verified | Build record / measurement required. |
Planning to transport the truck?
Measure fixed exterior width and mirror width separately, plus overall length, the highest accessory, fifth-wheel height and actual transport weight. Interior bunk width is not exterior width.
03 / UNDER THE SKIN
Powertrain & chassis
Read the engine tag and original build record. 6×4 · November 2021 factory drawing. Read engine, gearbox and axle ratings together.
Numerical powertrain ratings need a dated configuration-specific source. MP-series and mDRIVE/manual possibilities vary by year and vocation.
Documented cab options
- Illustrated day cab
Documented transmissions
Read the installed unit’s identification plate and build record.
The manual identifies CHU as axle-forward Pinnacle and CXU as an earlier Pinnacle designation. The illustrated dimension boundary and front bumper control these values; a marketed BBC or another bumper may differ.
04 / MODELS, YEARS & CHANGES
One badge.
Different reference points.
Publication dates and launch milestones do not establish continuous model-year ranges. Match the VIN, production date and equipment era.
Identify the actual truck
The highway brochure places Pinnacle in a broader MP-series and Mack transmission context. A specific gearbox, sleeper and rating still needs a dated order record.
Mack highway factory brochure · GHG17-era, undated · dealer-hosted ↗Inspection and build evidence
Inspect vocational wear, corrosion, frame, suspension, cooling and transmission integration.
- exact Pinnacle designation
- engine/transmission tags
- axle layout
- frame/fifth-wheel data
- application history
05 / PUTTING IT TO WORK
Match the trailer to the whole truck.
Pinnacle axle-forward/axle-back and tractor configurations require build-level review.
HIGHWAYTRAILERS.CA
Flatbed
Start with deck length, load placement, axle distribution and cab-to-trailer clearance.
Read the guide HIGHWAYTRAILERS.CAStep deck
Compare deck height, gooseneck geometry and the loaded combination’s height.
Read the guide HIGHWAYTRAILERS.CARGN / equipment hauling
Check neck compatibility, fifth-wheel loading, wet-kit requirements and the complete axle layout.
Read the guide HIGHWAYTRAILERS.CAHow trailer capacity works
Review the tractor, coupling, trailer, tyres and load as one combination.
Read the guidePulling a trailer
Confirm build-specific combination, axle, tyre and coupling ratings, kingpin and service connections, clearance and actual axle weights. GVW is the loaded truck; GCW is the loaded combination. Neither is trailer payload.
Moving the tractor as cargo
Give the carrier measured length, exterior and mirror widths, height, ground clearance and transport weight. Assess deck access, breakover, loaded height and securement together.
Deck height & loaded height ↗There is no single “Pinnacle towing capacity”.
The model badge, artwork and catalogue option selectors cannot rate an individual combination. Obtain the actual build limits and scale weights.
06 / FOLLOW THE EVIDENCE
Sources & open questions
Reviewed September 7, 2026. Manufacturer figures remain tied to their stated reference; converted equivalents are rounded; original source units are retained. Application and inspection notes are editorial guidance.
- Mack PI / CHU613 axle-forward drawing · November 2021 · page 64 ↗
- Mack CXU613 axle-back drawing · November 2021 · page 61 ↗
- Mack body-builder Section 0 · November 2021 ↗
- Mack highway factory brochure · GHG17-era, undated · dealer-hosted ↗
- Mack — truck lineup and legacy Pinnacle ↗
Reference-specific evidence needed
- Add verified sleeper editions and engine/transmission rating matrices.
- Establish production boundaries for Pinnacle designations without treating the manual’s review date as a model year.
- Obtain build-specific overall length, exterior and mirror widths, overall height, fifth-wheel height and actual weights.