So the truck just started doing a little something strange a couple of months ago. When I start it up it runs just fine, but when I hit my first stop light (about a mile away) I will stop the truck and it will idle for a second or two and all the sudden the RPM's will drop from a normal 700-800 down to 500 and it will feel like it just shifted into gear and pushes the truck forward. Sometimes I will come to a stop and it has just bottomed out the RPM's and died. It always restarts and has never slipped a shift and the shifts are really solid. This will only happen a maybe a couple of times if I hit lights before everything is warmed up. After I have driven a few miles there is no hint of this at all. Im just trying to figure out what it is. Im thinking possibly a shift solenoid, but am unsure. Transmission was flushed 10k miles ago and has amsoil in it along with a wix filter. The shop that did it said everything looked great in there. Any ideas?

 

Well, first off, I have heard from some of the terrific mods that flushing the transmission fluid almost always leads to some problem, and that it is better to swap it out in smaller amounts over time.......I think it was Hammer who said it. As for the solenoid, I think you may be right, but I don't know a ton about trannys.

 

have you checked the tranny fluid level? These trucks always need to be topped off after a transmission fluid change. Low fluid will give you many of the problems you describe.

 

I have a similar problem as well. Dealer flushed trans @ 30K and I now have 52K. Anyway, transmission shifts fine at all speeds & temps but sometimes when I come to a stop light and after sitting still for a few seconds I feel a slight jolt forward, similar to another vehicle tapping your bumper. In fact the first time it occurred a year or so ago that is what I thought happened.

Anyway, no drop in RPM when this happens or other known problems with transmission but it sounds like it could be similar in nature to your issue that I am attempting to figure out as well.

 

Flush the amsoil out. I wouldn't use anything but atf+4. Sometimes factory fluids are just better

 

Low fluid can certainly cause so.e of those issues described. IDK how Amsoil does in our trans honestly.