# Peterbilt 379 Used Price & Common Problems | Big Rig Risk

> Peterbilt 379: used $39,995 to $79,950. Documented problems: cylinder head and block. What to inspect before you buy.

**Verdict:** insufficient-data

Documented failure points and real market prices for the Peterbilt 379, sourced and dated.

**Observed used price:** $39,995–$79,950

**Documented failure risks:**
- Fuel Injectors (Cummins ISX15, common Pete 379 spec): ISX15 injectors fail by sticking open or closed, a common spec option in Peterbilt 379 conventional trucks.
- Injector cups and solenoids (Cummins ISX family): Injector copper sealing cups crack from heat cycling, leaking combustion gases past the injector seal.
- Cylinder head and block: Peterbilt 379s were heavily spec'd with Cat C15/C13/3406 engines; overheating these engines can crack heads or warp the block.
- Turbocharger (legacy Caterpillar twin-turbo C15): Turbo bearing damage on twin-turbo C15s is expensive to repair when warm-up procedures aren't followed.

## Sources
- [skylinerrepaircenter.com (failure evidence)](https://skylinerrepaircenter.com/blog/cummins-isx15-engine-problems-a-mechanic-s-perspective) (accessed 2026-09-05)
- [skylinerrepaircenter.com (failure evidence)](https://skylinerrepaircenter.com/blog/injector-problems-in-cummins-isx-engines-complete-guide) (accessed 2026-09-05)
- [skylinerrepaircenter.com (failure evidence)](https://skylinerrepaircenter.com/blog/caterpillar-truck-engines-legacy-maintenance-guide) (accessed 2026-09-05)
- [soarr.com dealer inventory (7 exact-model listings)](https://www.soarr.com/for-sale/trucks/0/Peterbilt/379/all-for-sale) (accessed 2026-09-05)
- [NHTSA recall 03V125000 (SUSPENSION:FRONT:HUB)](https://www.nhtsa.gov/recalls?nhtsacampaignnumber=03V125000) — "ON CERTAIN TRUCKS EQUIPPED WITH TRUCK HUB UNITS MANUFACTURED BY SKF EXCLUSIVELY FOR USE ON ARVINMERITOR'S FF98X SERIES NON-DRIVE STEER AXLES, THE HUB UNIT BEARINGS CAN WEAR PREMATURELY." (accessed 2026-09-11)
- [NHTSA recall 08V099000 (SERVICE BRAKES, AIR:SLACK ADJUSTERS)](https://www.nhtsa.gov/recalls?nhtsacampaignnumber=08V099000) — "PACCAR IS RECALLING 130 MY 2005-2007 KENWORTH C500, T800, W900, AND PETERBILT MODELS 357 AND 379 TRACTOR TRAILERS EQUIPPED WITH FABCO SLACK ADJUSTERS ON SISU AXLES.  THE SLACK ADJUSTERS MAY FAIL AS A RESULT OF A FATIGUE CRACK RENDERING THE SLACK ADJUSTER INOPERATIVE.  THIS COULD REDUCE BRAKING EFFECTIVENESS." (accessed 2026-09-11)

_Last verified 2026-09-11. Source: Big Rig Risk — https://bigrigrisk.com/trucks/peterbilt-379/ — every claim checked against a primary source before publication (see /methodology/)._