Delayed "Lockup" on Torque Converter
 

I've searched and searched and can't find a thread that remotely answers this. I've driven dad's 2000 Explorer and it doesn't seem to do this and he does absolutely nothing to maintain his vehicle. So here goes:

4r44e Trans. It takes at LEAST a half mile of steady 60 mph before the torque converter locks and drops the RPM to about 2100. On a cold day it will go a mile or so before locking. Is this normal?

I've found that if I turn off the O/D it will lock faster and drop to about 2700 at 60 mph in roughly a quarter mile, I can then hit the O/D again and it'll drop down to 2100 and stay there until my foot changes or speed drops due to a hill. Also, the shifting doesn't seem very firm, kind of lacking. IDK. O/D light does not blink, no codes stored or otherwise.

If this is normal, then so be it... if not, any fixes? I just find it unusual that it would wait so long. I have other questions about it but I suppose that should be in another thread... but it may be due to the transmission. I added to vehicle mods to explain its past: Ford Ranger Forum - The Ultimate Ford Ranger Resource - View Profile: davethepear

theres a how to on a lock up switch i have it

I seriously considered that... still unsure if I want to force it to lock and am concerned about frying the computer if I hook the wrong thing to the ground.

Are we ONLY talking about when the truck itself is cold? Is this a new behavior?
If so, the shift strategy is different when cold and will take a little longer to lock the torque converter, but that still seems excessive.
I guess the other obvious questions are (a) what is the ATF level and (b) when was the ATF last flushed?

No, just takes much longer when colder.
Recent fluid/filter change.
IDK if it's new behavior, I haven't had it long.

if its when its colder out its because the computer will NOT allow it to lock up until the trans is over 100deg most ford's and other manufactures are the same way. I have a trans temp gauge on mine and its around 110deg it will finally allow it to lock up its completely normal

It continues to have sluggish shifts and late lockup even after it's warmed up. Maybe the thing thinks it's cooler than it is. I'm almost to 150k. I shall try replacing a few things next fluid change... if it lasts that long.

Delayed lock up in OD is normal for a cold tranny. I would get that transmission serviced pronto

It's got an external cooler, bypassing the radiator, maybe it's not warming up? I'll visit a transmission shop with my credit card and see what they'll offer to do to me.

LOL

Starting to see that my "problems" are normal... (I'm also on therangerstation.com, same username, same avatar)... and a few others. It never hurts to have multiple opinions & ideas.

I've had it locked in 4-Hi since Sunday, occasionally putting it in 2 (the highway has no snow/ice), it's been doing fine lately. It does seem to "slip" out of 4wd on occasion and the back slides, then it catches and rights itself. Weird. I'm pretty sure I have a live front axle... I haven't looked, it's too cold to worry about at the moment.

This is a live axle, right?

http://farm6.static.flickr.com/5086/...e84f68a0_m.jpg
TruckHub by daveisapear, on Flickr

yes that is live front axle. inspect the front axle to see if it has a vacuum disconnect on the passenger side. if not, the transfer case shift fork and cam are worn out and it will not hold 4x4 under accelleration.

change the transmission fluid and filter for the delayed shifts and lockup. if this does not fix it, the separator plate gasket may be blown. replace the separator plate gasket, adjust the bands and the EPC solenoid and give that a try. The delay in converter lock up when the trans is cold, is because the PCM uses the torque converters fluid shearing capabilities to warm the fluid before allowing converter lock up

I changed the fluid/filter a month ago. Now that it is nearly 0°F (-17.8°C), it doesn't even bother locking that thing up on most trips. I've not driven it on a warm day... my cousin has owned it since new, but he's oblivious.

any idea where that temp sensor is for the transmission? maybe it's gone stupid... or the wire is corroded, or missing, who knows.

lots of ideas on where to stick a temp sensor, but none stating where the one the PCM reads is... not that I can find anyway.

Am I understanding correctly that the transmission cooler is not stacked with the radiator, as in it was changed? Do you have a scangauge or any other tool to measure the transmission temp?

The lines run to the transmission cooler and back to the trans, I don't know if the radiator was changed, I just don't know. Yes, and the PCM didn't care to share the trans temp with me. Wondering if the trans temp sensor is shot... where would it be located?

The trans temp sensor is part of the internal trans harness and would require the internal harness to be replaced in order to replace the TFT sensor

well that's a pain in the ass... *sigh*
thanks though.

Oddly enough it's been doing rather well lately... hmm. I looked closely, the transmission cooling lines bypass the radiator completely, only using the auxiliary cooler... I don't even see where it could be hooked up even if I wanted to. I'm always smelling antifreeze when I get out after a drive. Maybe it's a radiator for (or from) a manual transmission vehicle? I looked at dad's 2000 Exploder, his go through the radiator as well as the auxiliary cooler.