Sorry if this has been asked but here goes.
I have a 1998 4L80E out of a 98 3/4 ton installed in my 98 1/2 ton 2wd I did not rebuild the tranny just changed the fluid and filter, has about 100,000 miles on it. While driving if I do an aggressive stop it will go into a phantom neutral ill rev the engine a little maybe 1000 RPM it will re-engage and be fine.
is this a precursor to failure?
Any input is very welcome, it has a wheatly tune on it he said he made it pretty much stock.

Thanks A.J.

 

Well damn, I had something similar happen to me today. I was in traffic, came to a stop, then when I started forward again the engine reved a little, maybe 500rpm or so then thump.. off I went. Didn't happen again, but sure felt strange. Torque converter is the first thing that came to mind, but I don't know if that's wishful thinking because I wouldn't mind upgrading that.

 

Try reproducing it, I can at will really strange like it is starving for fluid but it is full.

 

Has it happened again?
Do you have any insight on this?

 

Two weeks after I put mine in it started doing weird stuff like that. Cruising around town in OD with a locked converter it felt as if it went to neutral and nothing would happen. I would have to pop it into neutral then back to OD for it to reengage. The shift quality also went to crap the same time the neutralling started. Talked to a local shop and read over some transgo literature and decided the TCC and AFL (actuator feed limit) valves were scored a little and letting fluid pressure leak off. The way I understand it the actuator feed oil is basically like the control pressure for the valves in the valve body. It is pressurized oil used to physically move the valves and so on. Anyway transgo has a valve body repair kit for these two valves. I pulled the valve body and took it to the local trans shop I had talked to and they installed the kit on both valves for $165 parts and labor and it hasn't caused a single issue since. My transmission was out of a 96 with 130,000 miles so you very well could be having the same issue.

 

What did the kit cost ya.

 

Here it is http://www.transmissionpartsusa.com/...-46930atv6.htm

That's not it I thing that is just the valves.
Hmmm not sure.

 

$165 parts and labor.

 

Thanks some times I need a good slap to see what is in front of me.

 

I have that problem where my eyes see and read one thing and my brain tells me something else or what I want to see and not what I actually saw. I asked the shop about buying the kit through them and they said it services something like half a dozen valve bodies so it would be cheaper to just have them do it then to buy the transgo kit for a lot more and have all these extra parts laying around.