First off, I have a 2004, 4x4, Supercrew, 5.4L. 140,000kms. So about a month ago I noticed that all of a sudden my truck would once in a while shift into second a lot harder than usuall. Over the last month, this problem has become more and more frequent to the point were it does it all the time now. The only time it doesn't do it, is if I shift through the gears manually, 1-2-D, or if I let of the gas at exactly the right time before it wants to shift, then it will shift smooth. Every other gear is totally fine, shifts like new. It also has decided to let me rev it all the way to the rev limiter now in first and it never used to let me, it always shifted before that before, it only does this from 1st -2nd though, no rev limitier from 2nd -3rd. Did some reading on here today, decided to check my fluid. It definitely is a little high. Not sure if this is causing it, or how it got overfull seeing as it hasn't been touched in months, but that will be fixed tomorrow. Is this a known problem with these trucks. Could it be something as simple as changing the transmission fluid? If it is, why only 1st - 2nd. Any help would be appreciated.

 

I'd be checking for a busted 1-2 accumulator spring.

Steve

 

x2

 

I have a similar problem when the truck is cruisng about 50 MPH and you let off the gass and then get back on it. If I ease into the throttle no problem. If I let off and get right back on...I get the clunk, and its pretty loud and noticeable. Truck has almots 100,000 miles and I have never had any problems. A suggestion of where to start would be helpful. Have never got a warning light or any fault codes.

 

Me 3.

Darrin

 

Yours may not be an actual 'problem' as such. There may be a reflash for your truck to address this. Maybe someone here knows for sure or maybe I can do a search later.

If not, I would start looking at the driveline for loose u-joints and such.

Darrin

 

busted 1-2 accumulator spring

 

I just picked up a new upper and lower 1-2 accumulator spring, my truck does the EXACT same thing as the OP describes. I have them sitting on my coffee table and when I get home I can give you the part numbers. Although I can't remember which one is the bottom one, the pink or the brown???? They were 13 bucks a piece here list, pretty easy and cheap fix for a tranny. If your Tranny have never been apart there is an updated accumulator valve that you should get too.

 

+1. Last time I had a 4r70W apart (you guys have the 70W's correct?) the pink spring was on the bottom, and the brown was the upper.

 

/\/\/\/\/\//\ Thanks! Now I won't forget! I can't go by what is in it, because it has a shift kit, but I want to go back to stock, because it shifts too hard with the blower, even before the spring broke.

 

does anyone have a diagram to go along with the part numbers?

 

I'm sorry, I totally forgot about the springs. I will take care of it after I get home from work tonight. I'll scan a diagram that shows the location of the springs and valve. I'll post the Part Numbers too.

 

Pink Lower Spring Part Number: F4UZ-7F284-A

Brown Upper Spring Part Number:F75Z-7F284-BA

I'm going to try and scan the diagram soon for location of the 1-2 accumulator valve and spring.

 

The 1-2 accumulator is the one you can see without taking the valve body off the bottom of the transmission. It is at the front of the trans (inside the pan), left hand side if you were sitting in the drivers seat. You will see a round hole with a large snap ring holding the bottom cover in. It is easiest to position a floor or bottle jack with a socket or a punch underneath it and slowly jack it up until you can release the snap ring. Then lower your jack and replace your springs.

 

I can't get my scanner to friggen work, but as posted above, use a floor jack , it works great, I just did it on the mustang taking it out was really easy due to a broken spring, and then I used the floor jack with a long 1/2 extension and a big socket to re-install.

Good luck!