2001 4.6L 4x4 4R70w Trans. 175,000 miles
The transmission fluid was power flushed about 40,000 miles ago & the fluid and filter (2nd or 3rd time) was changed 500 miles ago.
OK guys, here is the problem (Driving me nuts)
When I accelerate and the transmission needs to kick down, I get a hard (But solid) shift. Sometimes while cruising @ highway speeds, the transmission will REAL QUICKLY try to downshift and then kick back into top gear with OD. I will feel the clunk and the tach will jump up about ~100 RPM and then settle where it was. This happens in about a 1/2 of a second if that long.
To me, it feels like something (Trans control solenoid, shift servo, etc...) is getting a bad signal or is weak.

All other shifts are nice and smooth.

Any Thoughts? ALL help is greatly appreciated!!!!

 

Sounds like your going to fast for it to kick down.
At a certain speed it wont downshift. It will try and immediately go back to OD.

 

phil6608:
I don't think I am going too fast because, it happens anytime I am going 40 or above. If I am going 45 and try to accelerate, it will kick down with a hard clunk and take off.

 

I worked on my truck with a similar problem for 1-1/2 years, replacing everything I could think of. Then came across a couple of posts that was talking about the PSOM which is located on the back of the instrument cluster. I went to the junkyard and found a 4x4 lightning that had the only cluster that matched and fewer miles, lol. So I swapped them and the shift problem went away. good luck.

 

A 2001 doesn't have a PSOM and you certainly can't swap clusters in an 01 easily due to PATS.


Since all shifting is controlled by the PCM, you'll probably need some advanced testing to identify the condition described. I doubt that you'll get anywhere without digging into the computer and the controls.

 

"project":
Thanx for the info. I figured that I might have to do that but wanted to try and exhaust the all of the cheap avenues first.
Today, while changing the oil I added some K&W Trans-X. I have heard that it is good at cleaning the varnish and deposits. It went a while between flushes and figure with 175K it couldn't hurt. I will let everybody know if it helps.

 

4X4 Lightning????
No such thing. One was never built.
ALL Lightnings are 2wd!

Phil

 

I have a 2006 F150 with 82k miles on it and i've had it for 2 weeks and have had the same problem where the truck slams itself into lower gear. Overdrive, or not, 30 mph to 75 mph its the same thing. When the truck is run first thing in the morning it doesnt do it until its been warmed up. In the past, with all of my friends who have owned trucks, i've known that this can also be complete transmission failure- aside from new Codes, new coils, and the dealership telling me it'll go away once the trans/engine wears to my driving style...i've got 2 weeks left on my 1 month warranty and this truck was also used to plow. Does anyone have any idea really other than an OD snap ring or fuel transfer issues what this means? Its slams hard enough that the dashboard creaks like im going over potholes. Not happy though with my first Ford so far--

 

That's YOUR fault for buying a former plow truck.

You are lucky you got any warranty at all with that previous history.

 

Doesnt matter what it did before, i know people that have f150's with over 120k and they never had any probs, and towed boats, and plowed about 3 times as much as this one did. Theirs were about 5-10 yrs old. Still doesnt answer my question. I've also had 4 Saabs with Ford motor blocks ranging from '83 to 98 and never had a problem with them thats why i chose a Ford. I'm not bitching about it because its a Ford, I'm wondering why this one didnt hold up like the '05 my Friend has who has 112k on it and has done far more plowing with it. Still dont know what's causing it-
The Leading Ford dealer in VT sold me this truck. Advertised through Fords website, i found all this fun stuff out after I bought it.

 

Well take it back before your 2 weeks is up or your stuck paying for the problem yourself!
Tell them to fix it!

And buying a plow truck all depends on who was doing the plowing!
Some guys are HARD on stuff!
My last truck was used for plowing (never knew to check for that) and revers went out of it.

 

Thanks for your suggestion, and not sure who plowed with it but youre right about that for sure..I brought it in again, and theyre trying to figure it out too. If theyre like me, it got used to plow pretty heavily. I will say that I drove the thing a mile up a logging road in 2 and a half feet of snow(no exaggeration) on my way up to a camp. It bogged down every ten feet or so but it was a tank, and made it uphill in conditions that anyone else would be crazy to do. 6970 lbs...Badass truck.. I'll get to the bottom of it one way or another. I Like the pic of you spinning them out, thats a fast truck for sure-