97 xlt xcab 4x4 4.0, M5OD, 192k miles, here's an odd one that i need anyone's help on, for at least close to 2 years now, i've been having more problems getting the tranny into gear after stopping at a red light and putting in neutral and then trying to get back into 1st to go. however the ODD thing about this is that it is temperature dependent, i.e. in cold weather, <45F, the problem mostly is gone and although still a little notchy, it shifts easily into 1st and any other gear while stopped. but once the weather gets above 45F, the problem suddently appears and it literally doesn't want to shift into 1st, or any other gears, at a stop, to the point that i am really jamming the shifter to finally get it to pop in. pumping the clutch multiple times does not seem to help much if at all. as well, i just noticed this the other day (weather in pa had a heat wave of 65 two days ago so the problem reappeared and already disappeared since it is cold again) that when trying to force it into 1st or 2nd, the truck did thunk and lurch forward a hair each time. last fall i did do a bleed of the clutch, as it was probably never bled (my dad bought this truck new) and it bled fine. i'm also 99% sure this is the original clutch if you can believe it. however, clutch pedal feel has and is always good. i also changed tranny fluid. there was some metal shavings/mud on mag drain plug (i had changed fluid 4 years prior). there is no evidence of any slave leaks and level has always been fine. so i need some opinions on what this is, tranny or clutch, or both? the whole temperature dependent thing has me stumped though. btw, i did do a full tranny/clutch/slave/etc replacement on my 89 ranger due to both a leaking slave as well as a trashed fm146 tranny, but this doesn't feel like the same failures. thanks in advance for any help.

chad

 

That's an interesting problem. My 5 spd behaves in the opposite way - more difficult to shift when its cold than when its hot. My explanation for that is that the fluid is thicker when its cold and the syncros drag.

However, in your case, dragging syncros may be having the opposite effect if they are badly worn. The problem may be compounded by a worn clutch/slave that is not fully releasing the clutch. Several recent threads have described different people having clutch/tranny problems. One of them described how you can determine how much travel is created by the slave. It seems to me that is the place to start looking to try to determine whether the problem is with the clutch itself, clutch release (slave problem) or transmission problem.

 

yep, i looked through all the posts and i printed that post and will check that bearing travel when i get a chance. it is interesting as i've never seen that info on checking travel before anywhere. regardless, yes, you can see why i am stumped with the odd temperature reaction of the tranny. you would usually assume the opposite like how yours is. also, if something is worn, why does cold weather make it behave like there is no problem??? we'll see if anyone else has any additional insight.

chad

 

My theory is that your clutch friction disc is sticking to either the flywheel or the splines of the transmission input shaft and therefore the clutch is not fully disengaging. Possibly temperature related because of some type of substance.
Like I said, just a theory.

 

it is easy to determine problem. first of all, bleed clutch. then try to get into 2nd to start (not 1st as usually). but you may have 2 problems in one. If clutch was not disangaged fully and you draw for long time with clutch problems, may be 1st gear synchro is worn now.

 

weather finally cooperated this weekend, so i got a chance to check out clutch/tranny. thanks to town car for his homepage which has the ford 1997 truck manual cd on it, after downloading and following the steps for clutch system diagnosis and testing, it appears my hydraulic system is fine but it tells me to "replace clutch disc, pressure plate, release hub and bearing, inspect splines on input shaft for wear" so it looks like the oe clutch is in need of replacement after 193k miles. hopefully that's all it is and the input shaft is fine. now to just get some more nice spring weather in the next month or so to do a clutch job. guess i have to research all that for the 4.0 (again i did a clutch/tranny job on my 89 2.9 awhile back, and hopefully this time it doesn't involve a trip to er...prybar slipped and i cut my thumb completely open on top which took stitches) i dread all those damn rusted bolts though...

chad

 

Lazy K is probably barking up the right tree. If the splines on the input shaft are dry, and possibly rusty, the disk can't "float" between the flywheel and pressure plate when the pedal is pressed. This causes a drag, slowly rotating the input shaft of the trans. As the temp gets warmer, the fluid in the trans gets thinner, and the shaft spins more freely. I had a similar problem in my '85 years ago. How far do you typically drive? If you drive for a while on a cold day, does the problem start to show up anyway? Just wondering. Just thinking out loud.

 

I see this truck with clutch and transmission problems on a regular basis come into my shop. When I have a situation that it is hard to get into gear when hot and when the hyds check out to be working the problem is usually the pilot bearing. The pilot bearing is in the back of the crank shaft and supports the tip of the input shaft of the trans, they dry out and start to turn the input shaft, this can make in hard to get into gear. Sometimes the bearing has worn the tip of the input shaft so bad that I have to replace the shaft or it will cause the new bearing to fail.