Transmission not shifting properly

1993 FORD F-350
156,000 MILES • 5.7L • V8 • 2WD • AUTOMATIC
Avatar
GAILMAC2000
  • MEMBER
  • 1 POST
My transmission will shift hard into second, but will not shift at all into third. I can manually shift from second to third and it works just fine. The light does not work on my overdrive button, so not sure how to know if in overdrive or not.

Any ideas what is wrong?

The transmission was replaced about eight years ago, but only has about 10,000 miles on it.
Thanks for any help.
Aug 9, 2018 at 6:30 AM
Advertisement
Avatar
STRAILER
  • ✓ASE Certified Mechanic
  • 54,837 POSTS
  • ASE Certified Mechanic
This sounds like a partially plugged catalytic converter which will change the engine vacuum readings causing the transmission to shift late. Here is a guide to help you confirm the issue:

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

Please run down this guide and report back.

Cheers, Ken

Aug 10, 2018 at 12:47 PM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.