This happens only when shifting from first to second. It will shift hard, and if I'm at WOT you can hear a squeal as well. The truck is a 2000 5.4l F150 w/ an auto tranny. It's got about 135k miles and I haven't changed the tranny fluid (stupid, I know) but I'm fixing to do that this week. I've reset the computer several times and it hasn't changed anything, I'm not getting any codes either. Like I said, it shifts fine through every other gear but first to second.

 

It's a very common problem. It's your serpentine belt. Accessories and engine are going full speed, and you downshift. Engine RPM drops, but accessories are still going full speed until the belt slows them.
Get a Goodyear Gatorback serpentine belt. It will stop the noise.

 

Alright, I'll give that a try. What about the hard shifts though? I'm reading it may have to do with the accumulator springs. Since all the parts for it are cheap, I figure I'll go ahead and replace the whole thing. Are there any specific springs/parts I need to ask for, or can I just walk into NAPA and as for the accumulator parts/springs for my f150?

 

sounds like something with the accumulater for the 1-2 shift. Its an internal problem, not the cheapest fix. You will need to take the tranny down and get inside to see whats going on... hard to tell with out actually feeling it tho... good luck bud!

 

everything I've read suggested I wouldn't have to drop the tranny to replace the accumulator components, and that those parts were pretty cheap. You're saying this isn't the case?

 

I'd do a full system fluid replacement first. 135k on the original fluid is way past when it should be done.

 

not on Mercedes... haven't had the "pleasure" on the Ford's so you may be right. It is most likely the seal on the accumulator, it is bad and not allowing tranny fluid to SLOWLY flow through, instead its just getting a quick rush of fluid, causing the quick, hard shift.
P.S. Did some looking around myself... looks like your right. I thought I heard on Ford you had to drop it to get inside... i was wrong. Sorry

 

I'm betting the lower accumulator spring broke. The accumulator probably isn't hurt.
Alan

 

I experienced a very hard/late 1-2 shift on my '99 after some rough off-roading last Memorial Day (I don't know if the shift problem and the off-roading were related). As i remember, the shift was late/hard regardless of the throttle position. I fixed it with a $10 1-2 accumulator spring. Replacement consisted of removing the trans pan, removing a large snap ring, pulling out the accumulator piston, and replacing the spring. Prior to the repair, the trans operated properly with the exception of the 1-2 shift. This repair was one of the most satifying repairs I've ever done, fixing what seemed like a major trans problem for $10! Good luck to you!

 

Changing the fluid fixed mine, it might do it once a year or so, don't know why, but before I changed the fluid/ filter, it did it daily.

 

almost positive you have a broken 1-2 acc spring. It is a very easy fix if you have some mech. skills. drop the pan let the fluid drain for a few so its not dropping on you. look to the front of the trans on the drivers side and you will see the piston and the snap ring. Push slightly on the piston and remove snap ring and the piston will come out and you'll most likely see the spring is broken. I have seen some of them color coded so see if there's any coloring on the spring. get a new spring and install same way you took it out. Replace filter and fluid while you are in there also.

 

Well, as I mentioned earlier about changing the fluid and filter, do that in addition to finding that spring. Mine acted retarded today and I'm going to dig in there soon enough. Merry X-MAS a hole, this will teach me to call it a jalopy the other day when the alternator crapped out.

Anyways, today, I'm driving around town a bit, all of a sudden, I kick it in the *** to pass some chick who decided to stop right in front of me. It kicked into first no problem then 1-2 no problem at WOT. I slow as the light changes, then green and I take off pretty average. I'd say I'm in third when all of a sudden it's like I kicked it in neutral. I rev a bit, 3-3500 maybe and let it come down, do this about 3 times and finally get the screetch. I figure it caught the gear and is ok. Nope, it does this about 4-5 times, after each rev, it catches and loses it thus repeating. By this time, I'm slowing to 40 km/h or less, so I pull off down a street and then kaboom, it's shifting fine. WTF, it has never done it this bad or did it once and never again for a while. I wonder in addition to the 1-2 acc. spring, could it be the 2-3 as well, or something else? I know basics of tranny's, but nothing in depth. I want to get this **** fixed soon if I could. Any more thaughts on this tranny guru's?

Sorry to muscle in on this thread, but maybe more can be said beyond the 1-2 spring, I was cruising at about 60 km/h and basically holding when it all of a sudden did it. I might have just gotten into third, didn't seem to notice it that quick so I figure it lost gear. Can anyone suggest more than the spring(s) or is that indeed it? Thanks for the help in advance.

 

My tranny has felt like it's been slipping for a couple of years now (long before my recent OD problem has surfaced)... what a PITA! Sure would like this fixed once and for all, but tranny shops scare me with 4 digit repair bills