OEM & Remanufactured Transmission Hard Parts

The Part Has to Be Right. We Make Sure It Is.

Every valve body, pump, solenoid pack, and hard part we sell is inspected by mechanics who have actually built these transmissions — not warehouse staff running a checklist. If it doesn't meet spec, it doesn't ship.

Shop Parts Verify Fitment
10K+
Parts Shipped
500+
SKUs In Stock
Lifetime
Replacement Warranty
Parts Catalog

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OEM and remanufactured. Every part inspected by experienced transmission mechanics before it ships.

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Valve Bodies
OEM & Remanufactured — Mechanic Inspected
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Solenoid Packs
OEM-Spec — Resistance & Function Verified
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TCMs
Ready to Program & Pre-Programmed Available
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Drums & Internal Hard Parts
Bell Housings, Extension Housings, Planets & More
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Transmission Pumps
Inspected for Wear, Clearance & Integrity
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Gaskets & Soft Parts
Seals, O-Rings, Gaskets & Filter Kits
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The KJHardParts Standard

What Sets Our Parts Apart

Genuine OEM Quality
We source OEM and factory-spec remanufactured components — the same parts the transmission was engineered around. No cheap substitutes that look right but fail under pressure.
Inspected by Real Mechanics
Every part is gone over by technicians who have personally built and rebuilt these transmissions. They know the failure points, the wear patterns, what to accept and what to reject. A warehouse worker with a clipboard cannot do what they do.
Held to a Higher Standard
If a part doesn't meet spec, it doesn't leave. Simple as that. We'd rather eat the cost than put your name behind a callback. Your shop's reputation is worth more than a quick sale.
TCMs: Ready to Program or Pre-Programmed
Depending on the application, we offer TCMs ready for dealer or aftermarket programming, as well as pre-programmed units for common applications. Verify fitment before ordering and we'll confirm which option is right for your vehicle.
Lifetime Warranty — Not a Gimmick
Every part carries a Lifetime Replacement Warranty. If it fails under normal operating conditions, we replace it. No time limits, no fine print designed to get you off the phone. We back what we sell.
VIN Verification Before You Order
Transmission parts vary by build date, engine, casting number, and drivetrain. Send us the VIN before you order and we confirm the correct part. Takes the guesswork out completely.
Don't Guess

Send Us Your VIN.
We'll Confirm the Right Part.

Transmission parts are not one-size-fits-all. The same vehicle can have multiple transmission variants depending on build date, engine, casting number, and drivetrain configuration. Ordering the wrong part costs you time and money. Send us the VIN first — it takes us a few minutes and saves you a headache.

Year, Make & Model
Engine & Transmission Code
Casting Number Verification
2WD / 4WD / AWD Drivetrain
TCM Programming Requirements
Build Date Variance Checks
Verify My Fitment
Fitment
Confirmed
No Fine Print

Lifetime
Replacement
Warranty

Every part we sell is backed by a Lifetime Replacement Warranty. That means if a part fails under normal operating conditions — we replace it. No arbitrary time limits. No hoops to jump through. No one trying to find a reason to deny your claim.

Read Full Warranty Policy
Defects in Materials or Workmanship
If the part fails because of how it was built or what it was built with, that's on us — not you. Covered, replaced, shipped.
No Time Limit
Lifetime means the life of the vehicle. We don't cut you off at 12 or 24 months. You ordered a quality part — we stand behind it as long as it's in service.
Replacement Ships Fast
Contact us with your order number. We process warranty replacements within 1–2 business days. We understand that a vehicle down is money lost.