5R55E Problem

[JDraper]

Well, been searching for a while, and can't find the exact problem I have in a 5R55E. At 45k miles, I appear to have lost 1st gear completely. Off the line, the truck is sluggish, and it hits about 55 without shifting. I only get 3 shifts with the OD off, and holding it in 1 won't engage 1st either. All the other gears and OD work normally, and I have no codes and no flashing OD light. The tranny was just flushed at the local Ford dealer about a week ago. Anyone else have this problem, or know of the solution? I saw plenty of posts on the "won't downshift into 1st" problem, and plenty of posts on problems that had either a code or the OD light flashing, but none on this specific problem.

 

[cjbarron5]

are you sure its 1st your missing or are you getting a partial engagement or dual engagement and no 5th i would take it back to ford since they are the last ones to have their hands on it ill check my book and post more later

 

[JDraper]

Well, after more test driving and debugging, it appears it was a t-stat problem. When the truck was cool, the tranny shifted just fine, as it warmed up, the tranny started acting up, and the temp was fluctuating from the middle of the gauge to not quite overheating. I could control the temp with the throttle, get on the gas, it went up, get off the gas, it went down a little. Let it cool down, the cycle repeated. Checked the antifreeze and was a little low. Talked to Spas and she had the same problem in her truck a couple of years ago, and her problem had been a stuck t-stat. Went down to Advance Auto, bought a new t-stat, installed it and presto, no more temp fluctuations and no more tranny shift problems.... :smoke:

 

[cjbarron5]

glad to hear that its alot cheaper than trying to fix a tranny