357

The Peterbilt 357 is a rugged, Class 8 vocational truck that was produced until around 2007. Known for its durability and customizable chassis, the 357 was a staple in construction, aggregate, and heavy-haul industries. It shares much of its design lineage with the Peterbilt 378 but was typically spec’d for more vocational uses.

The 357 was widely used in:

• Dump trucks
• Cement mixers
• Lowboy and equipment haulers
• Heavy-duty plow trucks
• Oilfield and logging operations

Its strength and spec flexibility made it a workhorse in off-road and vocational sectors.

Cab Type

• Cab Style: Vocational conventional cab
• Cab Width: Approximately 1.9 meters (75")
• Shares a narrow vocational cab shell with other Peterbilt models like the 340, 335, and earlier 348s

Aftermarket Seat Compatibility

The Peterbilt 357 uses the standard vocational bolt pattern of approximately 4.68" x 12", which is widely supported across most aftermarket seat manufacturers.

Common aftermarket options:

• National Admiral, or Commodore – fits with standard pattern
• Bostrom T-Series or Pro Ride – air ride or mechanical versions
• Knoedler Air Chief or Harrier – fits standard vocational pattern
• Gramag seats – generally require no adaptor in this cab

Installation Notes

• No adaptor plate is needed in most cases—standard vocational pattern applies.
• If your 357 has been modified or has a raised floor, check seat height and suspension clearance.
• For premium upgrades (heated/cooled seats or massage), verify your truck’s 12V power availability under the seat.