Diagnostics7 min read

Valve Body Issue or Software Issue

Expedia Protection

Up to 5-year warranty on reman and used parts when fitment is verified.

See warranty details →

Expedia Protection

Up to 5-year warranty on reman and used parts when fitment is verified.

See warranty details →

Expedia Protection

Up to 5-year warranty on reman and used parts when fitment is verified.

See warranty details →

Harsh shifts and wrong gear commands after a transmission swap may be reflash, adaptive relearn, or harness issues — not a valve body defect.

Quick Answer

After a transmission replacement, **harsh shifts or wrong gear commands** often mean **reflash not completed**, adaptive tables not relearned, or a harness/range sensor issue — not a defective valve body on arrival.

What shops verify first

1. Reflash/programming completed for VIN and calibration. 2. Adaptive drive cycle performed per OEM procedure. 3. Range sensor and harness fully seated. 4. Correct ATF spec at hot level. 5. Stored codes documented before and after repair.

FAQ

Can a valve body be bad out of the box?

Possible but uncommon — software and vehicle-side causes are ruled out first.

What proof does warranty need?

Reflash invoice, scan reports, and fluid receipt when applicable.

Related on Expedia Parts

When transmission needs reflash: /blog /when-transmission-needs-reflash
Won’t shift after install: /blog /reman-transmission-wont-shift-after-install
Pre-authorization: /blog /pre-authorization-before-removing-unit
Shop transmissions: /used-transmissions