ROUGH GEAR CHANGES

Aging transmissions are often prone to rough gear changes. Sometimes, fluid may be contaminated by dirt and debris, and replacing it will fix everything. Other times, it’s only because the car is getting quite old and the transmission is not in top shape anymore.

Troubleshooting procedure:
When trying to fix rough or jerky gear changes, the first thing to inspect is:
i. The transmission fluid. Make sure it’s bright red and free of any metal shavings and debris.
ii. If it’s dark, muddy, or has a strong burnt smell, replace the fluid and the transmission filter right away.
iii. When in doubt, it’s always better to start by replacing the fluid since it’s the cause of most automatic transmission problems
iv. If it didn’t do it or your fluid looks fine, scan the TCM for codes. You may be lucky and find a code telling you what’s wrong right away or find the meaning from our search bar.
v. Take a look at the live data and perform live tests to ensure all the valves are doing their job.
vi. A neat trick is also to erase the learning data of the module. New transmissions learn from your driving habits, and corruption of the data may occur with time. Resetting it could fix the problem.
vii. If everything looks fine and you still have jerky gear shifts, worn internal components may be the answer. In that case, there’s not much you can do, and you might have to buy a replacement tranny altogether.
viii. It’s worth mentioning that specialized fluid additives can help with jerky shifting. While these products might temporarily help, you should probably seek the help of a mechanic anyway. Try one of these when everything else fails.