how to fix a slipping transmission

How to Fix a Transmission Shudder

by Jack Hathcoat

New car engine gearboxes image by Christopher Dodge from Fotolia.com

Transmission shudders seem worse than they actually are. Shudders occur most often when shifting into overdrive or when in overdrive and going up a slight incline. This occurs because the transmission fluid is contaminated and the contaminates, being suspended in the fluid, prohibit good pressure contact between the transmission plates when they are applied. Routinely servicing the transmission prevents this from occurring. Left unserviced, the condition will worsen.

Step 1

Jack up the front of the car and install jack stands under the frame. Lower the car and make sure it is securely positioned on the stands.

Step 2

Use a socket wrench to remove the transmission pan bolts and remove the pan. Drain the fluid into a drain pan. In some cases, there is a drain bolt in the pan, usually on foreign vehicles. In these cases, remove the drain bolt to drain the transmission.

Step 3

Replace the pan along with a new pan gasket. Scrape off the old gasket with a gasket scraper, making sure the pan is clean. It is not necessary to replace the transmission filter if the car has low mileage. However, replace the filter, regardless of the mileage, if the fluid is dark and discolored. Remove the jack stands and lower the car.

Remove the transmission dipstick and insert a funnel into the dipstick tube. Estimate the amount of fluid that was removed by checking the drain pan. Add new fluid according to the estimation. Start the car and let it reach operating temperature. Check the fluid amount with the dipstick and add fluid to the recommended amount.

References

Tips

Some vehicles are not equipped with dipsticks or filler tubes. These are difficult to service. Follow recommended guidelines to service these units, or have a professional lube shop perform the service with their specialized equipment.

Things You'll Need

Jack
Jack Stands
Drain pan
Gasket scraper
3/8-inch socket set
Funnel

Warnings

Depending on the manufacturer, check the transmission fluid level with the car in park or neutral. Be sure to set the parking brake.

Writer Bio

Jack Hathcoat has been a technical writer since 1974. His work includes instruction manuals, lesson plans, technical brochures and service bulletins for the U.S. military, aerospace industries and research companies. Hathcoat is an accredited technical instructor through Kent State University and certified in automotive service excellence.