# 4l80e not downshifting



## jb1390 (Sep 23, 2008)

What the title says....I can manually select a range, and the truck will go to that gear after quickly cycling through the others. I an manually downshift-from OD to 3 to 2nd, by moving the lever. It won't jump on its own due to engine load/speed, even to the point that it will almost stall out the truck. No check engine light. 

Transmission was rebuilt 2 years ago. I just did a fluid change about a week ago...shifts are smooth and everything feels normal except for it not downshifting on its own like it should.


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## Davidl79 (Nov 26, 2010)

http://www.454ss.com/Articles_new/red/4L80E_Transmission_Problems.asp This website may help. Might just be a loose wire on a solinoid.


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## jb1390 (Sep 23, 2008)

That is some wonderful information. Thank you very much Davidl79. 

For now-the truck seems to be acting just fine. I am going to change the fluid again once we get a lull in weather-and change the filter as well. Looks like it could be as simple as a little crud getting stuck in a valve-adding clean fluid maybe loosened something up causing this issue. I'll keep my fingers crossed for now-the tranny is only a couple years old, I certainly hope they last longer than that between rebuilds.


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## BigLou80 (Feb 25, 2008)

jb1390;1216993 said:


> That is some wonderful information. Thank you very much Davidl79.
> 
> For now-the truck seems to be acting just fine. I am going to change the fluid again once we get a lull in weather-and change the filter as well. Looks like it could be as simple as a little crud getting stuck in a valve-adding clean fluid maybe loosened something up causing this issue. I'll keep my fingers crossed for now-the tranny is only a couple years old, I certainly hope they last longer than that between rebuilds.


mine has gone 200,000 with out a rebuild FWIW


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