5.0 Transmission Problem

[CougarX]

After offroading the other day my transmission began to give me problems. At first it would not idle in gear unless you gave it a little gas to keep it from bogging down. It acted like a manual when you don't give it enough gas when you let out the clutch, it would just seem like the transmission was dragging it down. It was fine in park and neutral but wouldn't idle in gear. After i got back to town and drove a little more and brake torqued it once for a couple seconds it was fine and drove like new.

The whole next day(saturday) it drove fine, no problems at all, no stalling or anything. But today it started acting up again. Now, instead of dieing when in gear, it jerks down into 3rd when you coast in overdrive. Its fine as long as you've got the gas pressed some but as soon as you let off to coast it jolts into third very hard and for a second, then shifts back into overdrive, then does it again until you get slow enough to stay in 3rd. Sometimes when I accelerate with about 1/3rd throttle it'll jolt shifting between 2nd and 3rd and then 3rd and overdrive, but not al the time. The truck is still driveable but its very annoying anytime you coast.

I've checked the fluid level, checked the linkages, and there are no CELs. What could be wrong with it?

 

[BradE.]

I'm not a tranny expert, but maybe you got water in it? Or could be the filter was knocked lose and your sucking air into the valve body, maybe a vac problem?

I've heard cases of the valve body bolts being loose on the 4R70W. Guess you will have to pull the pan and see what's going on.

 

[CougarX]

I didn't really want to pull the pan but if no one else has any other ideas i'm gonna have to just to check.

If there were water in it it would show up in the fluid on the stick wouldn't it? and if the valve body was lose or the filter was off wouldn't it affect all shifts?? I'm not trying to smart off or anything, i'm just trying to learn. I know a lot about cars and do everything to mine myself, but transmissions are one thing i have never got into yet.

 

[james t]

check the valve body bolts. backing loose is a semi-common problem with them on the 4R70W. it can cause all sorts of problems from mild to wild.

 

[DarkFox1]

you've got lemoneers disease hehe

if I were you I'd take it to cottmans, they have that nice free 21 point inspection, should narrow it down for you, they drop the pan and drive it too, only takes a lil while too

sorry, only info I can be of help with

 

[CougarX]

Ok, its getting worse, now sometimes it will drop out of gear when i take off. If i put it in second it avoids this. The fluid is also getting very hot and the auxillary cooler in the front is not getting warm at all. I'm going to drop the pan tonight and check that the filter hasn't come loose and that the valvebody bolts are tight. It started acting up after i was offroading and on some pretty rough roads so loose valvebody bolts would have gotten worse and the filter could have come off. Both these would cause flow problems so that the auxilary cooler wouldn't get warm. But i've got to go back to work now so it'll have to wait till tonight. Fortunately i've got my brothers truck to drive today so i don't have to do anymore damage.

 

[CougarX]

Ok, Filter and fluid didn't help... Valve Body Bolts were fine.... what else could it be... please don't say i need a new tranny, give me other options, i'm not putting a tranny in it and going through all that crap like i did last time with my old truck. I'll trade it off first. HELP!!

 

[CougarX]

Ok, no one gave me any more options, so i guess i need a new tranny
Gonna take it in on monday mornin to a couple places and get opinions.
Been lookin on EBay and those dodge cummins are lookin pretty good... gotta get this thing fixed before i go and buy one!

 

[BradE.]

Hmmm, the cooler is not warm? Maybe you bent a tranny line while wheelin'? Anything is possible I guess. If the fluid is overheating it can cause your problems. What tranny fluid did you put in it? 4R70W trannys should be on Mercon V. I have noticed with my 4R70W (not in Explorer) that Mercon V really requires a break in period before you will notice anything.

 

[CougarX]

I checked all the lines and none were bent, and yes i used Mercon V. I've run prolly a hundred miles and it hasn't got any worse nor any better. If it were a mechanical problem it seems to me (although i know next to nothing about auto trannies) that it wouldn't have come on so quick (overnight) and that it would be getting worse (over a week). I'm thinking i might have got one of the handful of electrical sensors on the side of the trans wet and messed it up but then again it seems like that would throw a CEL.

If i take my Apten Chip out it gets quite a bit worse. I assume all the chip does is increase line pressure to do what it does?... If thats the case could my pump be out or a line be blocked or partially clogged somewhere? Why else would increasing line pressure make it considerably better?

 

[james t]

if the pump was out, it wouldnt shift at all. sounds like a blocked line. have it checked out, as its hard to diagnose trannys online.

 

[CougarX]

I was reading my service manual CD and got a procedure for checking fluid flow through the lines, i'm gonna check it out tomorrow after work before i take it in monday and pay someone to fix something that i could have fixed.

 

[CougarX]

took it to ford... tranny is gone.... $2100.... 88000 miles.... i hate ford transmissions...

 

[Nate1]

Sounds like they just stole $2100 from you. Seriously sounds like a blocked line! What did they say was the problem. Did you get any other opinions?

 

[CougarX]

I havn't paid yet, took it in this mornin and they called and told me that i need one. I'm going in the mornin and talk to them and see what they say before i tell them yay or nay. I'm going to ask them about the lines and exactly whats wrong with it. The thing is, by the time i drove it far enough to get to the city where the dealer is the fluid was toasted and it was shifting much worse. So I don't know if I killed it or not. I know one thing, if i end up dropping 2 grand on a tranny the first thing i'm going to do when i get it back is put a tranny temp guage, external filter, and maybe a bigger auxillary cooler.