Help please

[Hunterturner0493]

We have a 2003 Ford Expedition 5.4 L 2 valve with the 4R70W transmission. So a little back story on it. We was pulling a camper down to lake moomal in va. The transmission was getting hot. So when we got back home i pulled it up on ramps and removed the transmission pan drained the fluid put new filter in and put the correct fluid back in. (When the trans pan was dropped there wasnt any metal in the pan or on the magnet. ) pulled it off the ramps after cycling it through park all the way down to 1 gear three times. Went to go up the road about a half a mile and it wouldnt go above 2000 rpms or 10 mph (limp mode). So i thought where the fluid was really bad I put new solenoid in the bottom of the transmission. That didn’t help. It’s got all new oxygen sensors in it. It has a new serpentine belt. New pulley new belt tensioner new mass airflow sensor. New thermostat new thermostat, housing new vacuum lines, new fuel filter, new cylinder head sensor. When I put a code reader on it, my long-trim fuel measures at zero on both bank one and bank two while short-term fuel trim measures at about .5 and up. It has 8 new plugs and 8 new coils as well as 8 new injectors. I also have new exhaust system on the way from manifolds back. To me its kinda like a fuel cut out when driving. It gets worse even going up hills. Im really hoping it isnt the clutch packs in the trans. Thanks for all the help in advance. Im in wv and in the haller we live in we dont get best of service so i will try to reply as soon as i can.

 

[NorthernExMax]

Does your transmission cooler have flow, or are the fins clean on it?

 

[Hamfisted]

Are you the original owner ? How many miles are on it ? How old is the fuel pump ? Can you do a fuel pressure test at the schrader valve on the fuel rail ? Should see 45-55 psi .

 

[Hunterturner0493]

Its a 2003 ford expedition. It has 1920032 miles. We havent done a pressure test. I actually need to purchase one so i can do one. We received our new cat back system today. We are hoping to have it put on tomorrow.

 

[Fastcar]

Its a 2003 ford expedition. It has 1920032 miles. We havent done a pressure test. I actually need to purchase one so i can do one. We received our new cat back system today. We are hoping to have it put on tomorrow.

Check the cat!

 

[Hunterturner0493]

Thank you we plan on trying to get our new one on tomorrow. I tried to take bolt out where manifold meets the exhaust but i cant get them myself without heating them up.

 

[NorthernExMax]

Its a 2003 ford expedition. It has 1920032 miles. We havent done a pressure test. I actually need to purchase one so i can do one. We received our new cat back system today. We are hoping to have it put on tomorrow.

I assume you have 192032 miles? That, or i am pretty sure that is the highest mileage expedition ever at almost 2m miles!

 

[Hunterturner0493]

Yes sorry. Its 192032 miles. I didnt see i put the extra 0 in there. Im sorry for that.

 

[NorthernExMax]

At 192k miles, that cat can still be good. A cat goes bad based off driving habits and poor maintenance. If I were you, id run some seafoam for a couple tanks and try cataclean, those both help clean up your exhaust.

 

[Hunterturner0493]

See the problem is you cant drive it that much. It will only go 30 mph and sometimes it wont even do that

 

[NorthernExMax]

See the problem is you cant drive it that much. It will only go 30 mph and sometimes it wont even do that

Are you sure the transmission is full of fluid, and making the pressure you require? Seems sorta to me you were on the right track and have since moved on to checking things not related. If you were getting up to speed and things worked fine before the transmission got hot, then your culprit is in the transmission, somewhere. You may need to remove the valve body and clean it, fairly easy on the 4r70 to do. The 4r100 was really the only “good” automatic transmission of its time for heavy loads, many of the 4.6 expeditions had transmission problems like crazy and the 5.4s were pepperes here and there.

 

[Hunterturner0493]

Well the reason i got away from the trans is because i had a mobile mechanic come out and look at it and they told me i had to fix the mis fires. And that it seamed to have a fuel cut out. But now after driving it more today i think the clutches are done for. It shifts fine if you keep it at low rpms or going down hill and its cold. Now if you go up hill, trans is warmed up the rpms will keep climbing but speed will not pick up and it will fall on its face shortly after and not go above 30 and then repeat itself.

 

[NorthernExMax]

Well the reason i got away from the trans is because i had a mobile mechanic come out and look at it and they told me i had to fix the mis fires. And that it seamed to have a fuel cut out. But now after driving it more today i think the clutches are done for. It shifts fine if you keep it at low rpms or going down hill and its cold. Now if you go up hill, trans is warmed up the rpms will keep climbing but speed will not pick up and it will fall on its face shortly after and not go above 30 and then repeat itself.

Man thats not good to hear. I think if you could get some information about the transmission, like if it is generating pressure or what the pressure is when warmed up, then you could find out if it is clutches or not. Do you have any problems getting into any gears? 1/2 shifts change anything? A bad pump and worn out clutches can be very similar if your pump is just on the edge. You said you did a filter and fluid change, do you have pictures of the old filter?

If you don’t want to tear into it, are you interested in a rebuilt trans, drop in a used/crate trans, or move on?

 

[Hunterturner0493]

With driving it i lean more and more to it being the trans. Im going to crawl under it again today and see if its the aod trans or the others. I was kinda hoping it wasnt the trans. I personally have never did trans work or even removed them from this type of car. Dont really have the money for the mechanic so I guess it’s gonna be a learning experience for me

 

[Fastcar]

With driving it i lean more and more to it being the trans. Im going to crawl under it again today and see if its the aod trans or the others. I was kinda hoping it wasnt the trans. I personally have never did trans work or even removed them from this type of car. Dont really have the money for the mechanic so I guess it’s gonna be a learning experience for me

That is how a bunch of folks here learned.

 

[GaryH]

It might be worthwhile to either buy an inexpensive OBD II monitor from Amazon, or if there's one close by, try one of the auto parts stores that perform free OBD II testing.

 

[pitdexion]

So did this problem occur after the transmission service? If so, is filter in correctly and proper amount of oil. Engine revving and not moving?