Shifting problems
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Shifting problems
Hey guys! I am having a problem with my 2000 F-250 SD Diesel and I haven't found anyone having the same problem. If I am in the pedal at all when it shifts into third gear it acts like it goes back and forth from 2-3 a few times before it goes on into third. If I am at WOT it will do the same thing but when I let off the pedal just a little it will go on into third. I had a problem with the tranny and I just had it rebuilt and the shop thought that would fix my shift problem, not a chance. They replaced the accelorator pedal but no fix. They unplugged the tranny from the truck and hooked it up to a box that lets you shift it from the cab and it did fine and it also does fine manually shifting. Could the computer maybe just need updating? Any help would be greatly appreciated. Thanks, Michael
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Well, an update for anyone looking at this. The Ford place has had it for the whole past week and they checked all the electronics on the truck and found nothing so they checked the line pressure and found that at wot shifting into 3 the line pressure was fluctuating between 90 and 150 which they said it should be at full pressure when at wot. The reason it is shifting fine when they hook the box up to it is because it bypasses the trucks computer and runs at full pressure all the time and was masking the real problem according to Ford tech line. They started checking valve bodies and thought they had found a problem in the accumulator valve body but Ford tech line told them no, so now they have determined the next place to look is in the direct clutch. So, $470 later on Monday it is back to the shop that did the rebuild and let them have another try at it.
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Sorry to hear of the problems you are having. Sounds like it wasn`t a problem for remote diagnosis. Thanks for posting the update, it may help someone else down the line. Good luck with it and hope you get it sorted out.
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Well I have another update. The transmission shop has taken it back out and replaced the direct clutch drum just because but said they didn't see anything wrong anywhere and it still does the same thing. They said they hooked the box back up and they can vary the line pressure on theirs and tried it at low,medium, and high pressure and it worked fine. So, the owner of the transmission shop knows someone at another local
Ford dealership so they are going to take it to them on Monday and see if he can figure anything out. I guess I am the only person in the country lucky enough to ever have had this problem.
Ford dealership so they are going to take it to them on Monday and see if he can figure anything out. I guess I am the only person in the country lucky enough to ever have had this problem.
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Hey guys, I have also noticed that when it shifts into third and is acting up the wastegate is bleeding pressure off and I don't have a boost gauge but it seems to me that when it shifts into a higher gear and rpms go down you would want to build boost for more power and not bleed it off. I know that there are several sensors that affect line pressure and shifting and it just makes me wonder if maybe one of them is acting up and causing the shift problem. Just seems funny that the only time the shifting messes up is going into 3rd and thats the only time I hear the wastegate bleeding off pressure. It has never set any codes for anything though.
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Well, for anyone looking at this, the service guy at the ford place called me this morning and said they wanted to try one more thing. It turns out the mechanic that had checked it out while they had it happened to have a pcm out of a truck like mine at his house and they wanted to swap it out and see if it helped. Good news, it runs like a top now, shifts great,no more waste gate bleeding off boost when it shifts into third and it even seems like the engine is a little quieter now. Maybe I'll get a little better mileage too. The best thing is that they just gave me the pcm and didn't charge anything for hooking it up.
