code 86 ?

[cudaaa]

I am having a problem with my tranny. Every so often it shifts in to 2nd gear and will not shift any more it stays in 2nd! If I turn the truck off and restart it the tranny shifts fine! The 86 code "low ratio error" what the heck is that? What does it take to fix! Any help is always appreciated. Thanks in advance.

[gmctd]

Try r&r'ing the two speed sensor connectors on the transmission, driver's side - each is a two-conductor plug. Has to do with engine input speed vs output shaft speed, and may be intermittent connection.

[cudaaa]

Thanks JD I'll give that a try this weekend!

[Marty Lau]

Mine does that when it's cold and I don't wait a minute or two before driving off. Change transmission fluid and filter has stopped it for a time.