TSB: KENWORTH 210, 220, 320, 325, 330, 337, 348, 357, 365, 367, 378, 379, 382, 384, 385, 386, 387, 388, 389, 389G, 520, 567, 579, 587, C500, T600, T660, T680, T800, T880, W900, W990 (2015–2020)

Bulletin 42-056 — August 28, 2019

Bulletin Details

Bulletin ID42-056
ManufacturerKENWORTH
Models210, 220, 320, 325, 330, 337, 348, 357, 365, 367, 378, 379, 382, 384, 385, 386, 387, 388, 389, 389G, 520, 567, 579, 587, C500, T600, T660, T680, T800, T880, W900, W990
Model Years2015–2020
Date IssuedAugust 28, 2019
Date Added to NHTSASeptember 4, 2019
ComponentENGINE AND ENGINE COOLING
Vehicles Affected123 combinations

What is a TSB?

A Technical Service Bulletin is a document issued by the vehicle manufacturer to inform dealership technicians about a known issue and the recommended repair procedure. TSBs are not mandatory recalls — they serve as repair guidance for common problems.

If your vehicle has this issue, bring this bulletin ID to your dealer. If under warranty, the repair should be covered at no cost.

Summary

Fix-As-Fail -??A? Composite fittings used in the cooling system may crack, resulting in coolant leaks. Brass fittings are available to replace the composite fittings.

Affected Vehicles

MakeModelYearComponent
PETERBILT 320 2020 060000 ENGINE AND ENGINE COOLING
PETERBILT 337 2020 060000 ENGINE AND ENGINE COOLING
PETERBILT 348 2020 060000 ENGINE AND ENGINE COOLING
PETERBILT 365 2020 060000 ENGINE AND ENGINE COOLING
PETERBILT 367 2020 060000 ENGINE AND ENGINE COOLING
PETERBILT 520 2020 060000 ENGINE AND ENGINE COOLING
PETERBILT 567 2020 060000 ENGINE AND ENGINE COOLING
PETERBILT 579 2020 060000 ENGINE AND ENGINE COOLING
PETERBILT 320 2019 060000 ENGINE AND ENGINE COOLING
PETERBILT 337 2019 060000 ENGINE AND ENGINE COOLING
PETERBILT 348 2019 060000 ENGINE AND ENGINE COOLING
PETERBILT 365 2019 060000 ENGINE AND ENGINE COOLING
PETERBILT 367 2019 060000 ENGINE AND ENGINE COOLING
PETERBILT 386 2019 060000 ENGINE AND ENGINE COOLING
PETERBILT 389 2019 060000 ENGINE AND ENGINE COOLING
PETERBILT 520 2019 060000 ENGINE AND ENGINE COOLING
PETERBILT 567 2019 060000 ENGINE AND ENGINE COOLING
PETERBILT 579 2019 060000 ENGINE AND ENGINE COOLING
PETERBILT 587 2019 060000 ENGINE AND ENGINE COOLING
KENWORTH C500 2019 060000 ENGINE AND ENGINE COOLING
KENWORTH T600 2019 060000 ENGINE AND ENGINE COOLING
KENWORTH T660 2019 060000 ENGINE AND ENGINE COOLING
KENWORTH T680 2019 060000 ENGINE AND ENGINE COOLING
KENWORTH T800 2019 060000 ENGINE AND ENGINE COOLING
KENWORTH T880 2019 060000 ENGINE AND ENGINE COOLING
KENWORTH W900 2019 060000 ENGINE AND ENGINE COOLING
KENWORTH W990 2019 060000 ENGINE AND ENGINE COOLING
PETERBILT 210 2018 060000 ENGINE AND ENGINE COOLING
PETERBILT 220 2018 060000 ENGINE AND ENGINE COOLING
PETERBILT 320 2018 060000 ENGINE AND ENGINE COOLING
PETERBILT 330 2018 060000 ENGINE AND ENGINE COOLING
PETERBILT 337 2018 060000 ENGINE AND ENGINE COOLING
PETERBILT 348 2018 060000 ENGINE AND ENGINE COOLING
PETERBILT 365 2018 060000 ENGINE AND ENGINE COOLING
PETERBILT 367 2018 060000 ENGINE AND ENGINE COOLING
PETERBILT 386 2018 060000 ENGINE AND ENGINE COOLING
PETERBILT 389 2018 060000 ENGINE AND ENGINE COOLING
PETERBILT 520 2018 060000 ENGINE AND ENGINE COOLING
PETERBILT 567 2018 060000 ENGINE AND ENGINE COOLING
PETERBILT 579 2018 060000 ENGINE AND ENGINE COOLING
PETERBILT 587 2018 060000 ENGINE AND ENGINE COOLING
KENWORTH C500 2018 060000 ENGINE AND ENGINE COOLING
KENWORTH T600 2018 060000 ENGINE AND ENGINE COOLING
KENWORTH T660 2018 060000 ENGINE AND ENGINE COOLING
KENWORTH T680 2018 060000 ENGINE AND ENGINE COOLING
KENWORTH T800 2018 060000 ENGINE AND ENGINE COOLING
KENWORTH T880 2018 060000 ENGINE AND ENGINE COOLING
KENWORTH W900 2018 060000 ENGINE AND ENGINE COOLING
PETERBILT 210 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 220 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 320 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 325 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 330 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 337 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 348 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 365 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 367 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 386 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 389 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 520 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 567 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 579 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 587 2017 060000 ENGINE AND ENGINE COOLING
KENWORTH C500 2017 060000 ENGINE AND ENGINE COOLING
KENWORTH T600 2017 060000 ENGINE AND ENGINE COOLING
KENWORTH T660 2017 060000 ENGINE AND ENGINE COOLING
KENWORTH T680 2017 060000 ENGINE AND ENGINE COOLING
KENWORTH T800 2017 060000 ENGINE AND ENGINE COOLING
KENWORTH T880 2017 060000 ENGINE AND ENGINE COOLING
KENWORTH W900 2017 060000 ENGINE AND ENGINE COOLING
PETERBILT 210 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 220 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 320 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 325 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 330 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 337 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 348 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 357 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 365 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 367 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 378 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 379 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 382 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 384 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 385 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 386 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 387 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 388 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 389 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 389G 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 520 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 567 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 579 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 587 2016 060000 ENGINE AND ENGINE COOLING
KENWORTH C500 2016 060000 ENGINE AND ENGINE COOLING
KENWORTH T660 2016 060000 ENGINE AND ENGINE COOLING
KENWORTH T680 2016 060000 ENGINE AND ENGINE COOLING
KENWORTH T800 2016 060000 ENGINE AND ENGINE COOLING
KENWORTH T880 2016 060000 ENGINE AND ENGINE COOLING
KENWORTH W900 2016 060000 ENGINE AND ENGINE COOLING
PETERBILT 210 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 220 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 320 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 325 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 330 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 337 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 348 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 357 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 365 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 367 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 378 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 379 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 382 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 384 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 385 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 386 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 387 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 388 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 389 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 520 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 567 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 579 2015 060000 ENGINE AND ENGINE COOLING
PETERBILT 587 2015 060000 ENGINE AND ENGINE COOLING

Related KENWORTH Recalls

CampaignModelYearComponentSummary
L770 2026 STEERING PACCAR Incorporated (PACCAR) is recalling certain 2026 Kenworth L770 and 2024...
W990 2026 ELECTRICAL SYSTEM: INSTRUMENT CLUSTER... PACCAR Incorporated (PACCAR) is recalling certain 2024-2026 Kenworth T680, T8...
W990 2025 ELECTRICAL SYSTEM: INSTRUMENT CLUSTER... PACCAR Incorporated (PACCAR) is recalling certain 2024-2026 Kenworth T680, T8...
W990 2024 ELECTRICAL SYSTEM: INSTRUMENT CLUSTER... PACCAR Incorporated (PACCAR) is recalling certain 2024-2026 Kenworth T680, T8...
T880 2026 ELECTRICAL SYSTEM: INSTRUMENT CLUSTER... PACCAR Incorporated (PACCAR) is recalling certain 2024-2026 Kenworth T680, T8...

What Should You Do?

If your vehicle is affected by this TSB, contact your authorized KENWORTH dealer. Bring this bulletin ID (42-056) when you visit. If under warranty, the repair should be free. If your warranty has expired, ask about goodwill coverage — manufacturers sometimes cover TSB-related repairs beyond the warranty period.

Frequently Asked Questions

A recall is a mandatory safety fix — the manufacturer must repair every affected vehicle for free. A TSB is an advisory document that describes a known issue and the recommended fix, but repairs are not required. However, some TSBs eventually lead to recalls if the issue poses a safety risk. TSBs are generally issued for quality or performance problems, while recalls address safety defects.

If your vehicle is still under the manufacturer's warranty, TSB-related repairs are typically covered at no cost. If your warranty has expired, you can ask the dealer about goodwill or customer assistance programs. Many manufacturers will cover or partially cover repairs for well-known issues, especially if the TSB was issued recently or affects a large number of vehicles.

Check the make, model, and model year listed above against your vehicle. If they match, this bulletin likely applies. However, TSBs may only affect vehicles with specific production dates, VIN ranges, or configurations. Your dealer can confirm by entering your VIN into their service system, which will show all applicable TSBs and recalls.

This data comes from the National Highway Traffic Safety Administration (NHTSA). Manufacturers are required to submit copies of all communications (including TSBs) sent to their dealers to NHTSA. The agency makes this data publicly available as part of its vehicle safety monitoring program.