4L60E Fail Safes

[Chris Ray]

Good Afternoon everyone,

I was curious as to what fail-safes the 4L60E has in place for downshifting too far. I was going up a 7% grade this weekend and accidentally went from 3rd to 2nd at around 70 mph. The cars running fine and I haven't heard any strange noises so far, but I was curious as to if the 4L60E would let me accidentally over-rev my engine by manual shifting it on the column.

PS: Has anyone experienced this as well?

Thank you,

Chris

 

[upper_tanker]

When I was younger (and MUCH more stupid), I went from drive to reverse on a 60e once on accident. It definitely let me do it, and it definitely did not appreciate me doing it.

Although I can't tell you for sure if you can drop it into 1st gear from 80mph or not, I'd be willing to bet that you can.

If you don't hear any weird noises and it's running as it should, I wouldn't worry about it. Also... if you have an OBDII-equipped Vortec engine (which you do if you have a 4l60E), you do have a rev limiter (if you have the stock fuel injection). I don't remember what it's set at when it's stock. I know about this rev limiter because when I was researching why people switch out PCMs from the black box to 0411, it's a known fact that the stock black box PCM will only allow for a max rev limit of 5800 rpm IIRC. This is just once of the many reasons why people switch to the 0411 PCM.

Sorry for the ramble.

 

[smdk2500]

. Also... if you have an OBDII-equipped Vortec engine (which you do if you have a 4l60E), you do have a rev limiter (if you have the stock fuel injection).

4L60E came out in 93.

 

[upper_tanker]

4L60E came out in 93.

I didn't know that. I thought all OBDII were 4L60E, and anything prior were 700R4 or 4L60. Thanks for the info

 

[smdk2500]

I didn't know that. I thought all OBDII were 4L60E, and anything prior were 700R4 or 4L60. Thanks for the info

yoiur welcome. Heres a post to a link on this forum that explains the differences in transmissions in our trucks. It is also a sticky in this sub forum.
https://www.gmt400.com/threads/the-real-differences-in-700r4-4l60-4l60e-transmissions-by-year.26587/