Our Remanufacturing Process

Every remanufactured engine, transmission, transfer case and differential Variety Engines sells goes through the same documented rebuild process before it is boxed. This page sets out what that process is, unit by unit, so you can read it once instead of on every listing. Each product page links back here to the section that applies to it.

Remanufacturing is not the same as a used part or a rebuild. A used unit is cleaned and resold as it came out of the donor vehicle. A remanufactured unit is stripped to bare components, measured against specification, and reassembled with new wear parts, then tested. Everything described below is done to meet or exceed OEM specifications for that unit.

Remanufactured engines

Engines run through four stages.

• Deep clean. The engine is fully disassembled. Cast iron components are hot tanked; aluminum components are thermally cleaned.
• Inspection. Magnaflux testing uses magnetic particles to find microscopic cracks and fissures in the metal that would cause a long-term failure. Every part is also inspected visually.
• Machining and new parts. Deck surfaces are CNC machined. New parts fitted include bearings, pistons, rings, lifters, oil pump, gaskets, Viton™ valve seals, freeze plugs and galley plugs, plus either a new timing chain with new tensioners or a new timing belt with a new tensioner. Where the engine uses a timing-driven water pump, a new pump is installed.
• SIM testing. After reassembly the engine is SIM tested: the cooling and oil systems are fully pressurized and the crank is spun at high RPM to verify compression and build quality.

Remanufactured transmissions

Automatic and manual transmissions run through three stages.

• Teardown and triple clean. The transmission is disassembled, inspected and cleaned three times. All threads are chased and all new bushings are installed during this stage.
• New or re-machined parts. Gear wear is checked and worn gears are replaced. Mainshaft straightness is tested and the shaft is replaced if it is out. Clutch disc synchronizers, selector fork and flywheel are re-machined or replaced as needed.
• Dyno testing. Custom dyno machines spin and load test every transmission to verify it is ready for the road.

Remanufactured transfer cases

Transfer cases run through four stages.

• Deep clean. Each case is fully disassembled and cleaned.
• Inspection. Each case is inspected for cracks, excessive wear, shaft warp and chain stretch.
• New components. All seals, bearings, joints and rings are replaced, along with electrical components — solenoids and control units.
• Validation. After reassembly each case is spin tested as part of a checklist validation process.

Read the shift notes on the individual listing before you order. Some electric-shift cases are listed with the shift motor not included; others include a new one.

Remanufactured differentials and axle carriers

Differentials and axle assemblies run through four stages.

• Deep clean. Each unit is fully disassembled and cleaned.
• Inspection. The ring and pinion, internal gears, clutches and carriers are inspected. Gears are checked for proper tooth contact and axle tubes are inspected for straightness.
• New components. All seals and bearings are replaced. Gears are reset for correct rolling torque and backlash is reset for quiet operation and longevity.
• Validation. After reassembly each unit is spin tested as part of a checklist validation process.

Gear ratio is what separates most carriers in a given axle family. Your replacement has to match the ratio of the axle at the other end of the vehicle, so read the tag on the differential or the RPO code before ordering.

Warranty and core charges

Every remanufactured unit carries a 6-month limited warranty as standard, running from the date of purchase and covering defects in materials and workmanship under normal use.

On qualifying remanufactured units a 7-year / 1,000,000-mile extended warranty and a core fee waiver are available on request. Neither is automatic. Both have to be arranged at the time of purchase, and eligibility depends on the specific unit and its application. The full terms, exclusions and claim procedure are on the warranty page.

Remanufactured drivetrain parts are sold as exchange units, so a refundable core charge may apply and your old unit goes back as the core. Call before you order if you want the core arrangement for your unit confirmed.

This process and this warranty apply to remanufactured drivetrain units. New shop equipment — lifts, compressors, tire changers, wheel balancers, brake lathes and cabinets — is covered by the manufacturer’s own warranty and is not remanufactured by us.

Before you order

The single most useful thing you can do is confirm the identifier on your own unit before ordering — the tag or casting number on a transfer case, the Hollander number, the gear ratio tag on a differential, or the VIN for an engine or transmission. Call 216-250-6666 or email sales@varietyengines.com with that number and we will confirm the fit against the listing before you spend anything.