I'm really getting tired of having to tinker with this F350 of mine. Now amonst all the other issues and spontaneous loss of power I'm not completly sure that my converter is functioning properly which prompts these questions.

1) How can you tell if the torque converter is locking up?

2) Counting shifts (hard and soft) can be tough. So, is an approximate drop in rpm by 300 is a converter lock up, and 500 rpm or more is a shift?

3) Since torque converter lock/unlock is controlled by the transmission (right?), if I disable OD does that disable the converter lockup also.

4) I read in another thread that the brake pedal operation signals the transmission to unlock the converter, right? If that is the case then tapping the brake pedal when the converter is locked should unlock it and rpms should go up. Right? I've never seen that happen.

5) Is there anyway to monitor the brake pedal signal with a volt meter or some kind of test light. If yes, where and how can you do this.

 

in response to #3:
If you disable O/D you will still have 1,2,3 shifts and tq lockup 1,2,3. you just wont have o/d and lockup in o/d.

I am new to the workings of torque converters as well so i will be paying attention to this thread.

 

iirc the torque converter will only lock up in 3rd and 4th but i could be wrong so with the o/d off it should still lock up in 3rd

 

1. when your in D and start from a stop,your in first gear.accelerate and you'll feel your first shift,which is now second gear.
keep going and you'll then feel it shift into 3rd gear (now the second shift you felt.) now pay attention around 35 mph.your about to feel a "odd ball shift" that doesn't quit feel like the previous ones did.this is lockup.then around 40mph (or higher of course if your taking off under heavy load/faster/uphill) you'll feel her final gear change into economy top gear - 4th/overdrive.

2.this varies drastically depending on how your taking off.the lockup is the shift dang near right on the $ @ 35mph,directly after 3rd gear.this is the one shift that will not shift early or latter depending on how much your giving her.she's going to lock @ this speed no matter how ya treat her. edit,no.perhaps thats not true.if you matted it,she would probably hold 2nd up past 35? i don't drive like this lol so i dunno.try it.stomp on it,to see if you can alter the lockup at a different speed other than 35 mph or so.could be fun trying.

3.lockup is controlled via the computer than runs the transmission.no.locking out OD via the button does not alter the converters lockup or unlock state.

4.iv read this as well.i sure can't tell.if im using the brakes,this means my foot as been off the fuel long ago and her coast clutch is engaged with rpms just above idle.you'd think if i hit the brakes and she unlocked that the rpms would go up,but it doesn't.perhaps the coast clutch trumps the tc lockup clutch.-i would think it would for economy,and im happy to say mines working correctly most likely like yours is lol.
so what i have to ask to those who notice a un/lock every time they touch their brakes....how the heck can you tell that lol? is your coast clutch not working?

from my understanding,most feel this and this is why they prefer the manual lockup mod.

i ran wires in the cab recently for diagnoses purposes.
anyway,i grounded the line going to the lock up solenoid ( temp lockup mod test.)
and what i found i LOVED! (just did this today) is that when she downshift from OD to 3rd ........oh baby!!!! the computer has her unlock prior to downshifting.man,when she couldn't do that but instead remain locked,the fuel economy spark in my brain lit right up. and at the same time,i kept my man card by enjoying that AWESOME direct downshift feeling.
i'll have to continue wiring this up permanently.
im not sure,but since this is like the feeling after installing a shift kit,only downshifting.that id guess they programed her to unlock just before kicking down for driver comfort.cus man that was a "high there,remember me,im 3rd gear again coming right back at ya." -not slowing down back into 3rd.that stayed the same,but i mean when you kick her down under load by giving her the oil.

im not sure i would have ever bothered actually doing this or not if it wasn't for my recent diagnoses reason.id kept missing the boat.
i didn't play with it til the end of the day though cus i wanted to be certain my prior issue was resolved.after 100+ miles i was pretty sure so i started playing once close to home this evening.pretty good stuff.
i couldn't tell any addition braking with it though-most likely due to the hydroboost now,iv got all i need and then some,and i was empty when testing.

5.there is a BOO (brake on/off switch) located on the pedal.
it just turns the lights on/off though.so im sure you'll just get 12v or nothing.
i see the computer doesn't tap into this switch though.it should have devoted pins for it.i gather due to cost ford tapped into the line downstream someplace simple and this is why if we loose a brake light the trans is no longer happy.-just a guess,but im pretty sure i must be right.-unfortunately.they could have done a better job with this,same with putting the dome light circuit on one of the important trans....uh duh! cutting cost when they put the brain in for the e40d that's for sure.
they do better today of course,but look at the price of the new ones too.

 

Thanks - Lots of info here. Will take time to digest but a couple of thoughts right up front:

1) OK - cool, great description

2) Will have to pay more attention here. Seems like I'll get my shift to 3rd early when I try to sneek up on it and then I'll be reving up to 2.5K before I hit 4th and never feel the lock up. One of the reasons why I think I'm having a problem. Will concentrate on the speedo more than the tach tomorrow and see what happens at 35mph

3) OK - thanks for confirming that. I figure I could disable OD and drive around looking for that lock up. I swear I tried that today and only counted 2 shifts. That's why I asked about the OD disable.

4) Hold the phone! Never heard of a coast clutch before. What does that do? As far as testing unlock via brake I was trying to use the brake pedal by left foot braking and keeping the gas pedal where it was to maintain speed. Figured if it was locked rpm would go up. Since I'm not sure it locked up in the first place I never felt any change.

Manual lock-up mode. Another new wrinkle. I've never heard that before so I don't know what you are talking about. And that goes for most of what you said after that. Sorry. I'm a gas guy with manual transmissions. I've bebuilt them and engines. This is my first diesel and automatic and it's frustrating dealing with all this seeming overly complex crap ford put in there. I don't even want to think about the Power stroke and stuff that goes on there.

5) Are you kidding me! A burned out brake light will effect the tranny? What effect will a trailer have and what happens when you put on the flashers? For crying out loud. Do you guys ever get a chance to just drive these trucks without having to worry about which gremlin is about to bite you in the butt next. All I wanted to do was pull my little race car to a track a couple of times a year. Every time I hook it up the trailer I have to put up with feeling of pending doom until I get back home. No joy here. I have none of these problems with my other daily driver and it's 43 years old.

I really do appreciate all the input here. Thanks and I'll be back again with another boat load questions.

 

to answer #5 and you'll like this one.......for now.
but get her up to OD (and then add 5 mph for good measure.) now put your flashers on.
this is another bad ford day.
the convertor will lock and unlock continually with the flashers.
this works great actually for you to test lockup.but a poor job wiring the trans by ford lol.BUT in their defense,how often does anyone need hazards on going faster that 35 mph really?
only reason i know about this is because i read it on a plow site with a guy warning everyone not to use flashers when plowing.but,this actually doesn't matter,as your not driving @ converter lockup speeds anyway when pushing snow.
i did try it once going down the road in OD to watch it unlock and lock back up in harmony with the flashers just to see lol.sure enough.
so if you want to test if you have lockup or not.turn on your hazards driving down the road @ 45 -55mph or so.if you don't see the tach spike up and feel it (you can't miss it) then for sure your convertor is not locking up.

#4.this is another real nice clutch! this one is also for fuel economy.what this one does,is semi opens the trans up to almost a neutral state when you let off the oil.she should drop her rpms way down low. this does depend on speed (if im going 45 downhill and let off the oil,she'll dang near hit idle rpms.i think i see about 900 rpm/my idle is 650-700.if your going faster she drops,but not as low),so it's not a complete neutral open state iv noticed.but a big help for FE no doubt about it,while going downhill.

#3 # 2. refer to the engineering flaw (or just cost shortcut,whatever the case was there lol.) in #5 you reminded me of.even easier test.

a lot of folks do in fact have a lot of problems with gremlims in the e40d circuitry.so much so,that they get frustrated and swap in 5 speed manuals.more folks prefer to deal with mechanical rather than electrical issues.iv always had manuals in my trucks in the past,and i know all too well about them repairs,and they are no picnic either lol.
im enjoying the e40d everyday and wouldn't change it for anything really.just a few small electrical issues i was able to resolve promptly so far.though iv got low miles on my rig.she just rolled over to 80k miles today.

 

OK, you got me. This is a joke right? Dancing to the tune of the flashers, really - lol

Now to be serious for a moment. I turned off OD and counted shifts. Nothing happens at 35mph no matter how I get there. I get 2 shifts. Looks like the TQ is not locking up at all. How do I troubleshoot this an id the problem. Is it in the TQ, the transmission, brake wiring, or somewhere else and how do I tell? Better yet, how do I get it working again?

 

sadly,no it's no joke lol.i tried it again today just for kicks.this time at just 40 mph or so.she just unlocked and stayed there for the 5 second test this time.

first thing to do,would be to remove the clip on the TPS (FIPL) throttle positioning sensor.clean it,and inspect the wires.apply some bulb grease and clip back in.
next get under the truck and do the same thing to the plug midway the trans on the pass side,just up above the pan.careful pulling this one out to inspect it.many folks have broken the clip.odds are she will pull out pretty hard.mine sure did.press inwards on the clips with just your fingers and pull upward like you really mean it.after cleaning these things,go for a test drive and see what happens.
when it comes to the E40D,9 times out of 10,the issue is nothing more than a sensor/bad wire,or some other minor electrical issue.it's just sometimes,finding the fault can be time consuming.start with the basics and work your way through the diagnoses process is all it takes.

 

I have seen, over the years, torque converters go bad and eat power. The transmissions will shift but they can make your truck feel like the brakes are dragging. I ran into this years ago back when C6's and 700 R4's were still installed. Not in these newer electronic transmissions. Still operate by the same principle though.

 

I was hoping it was a joke - what a stupid design. And no one has come up with a work around for this?

Thanks - will try both of those tomorrow. If that doesn't work where do I go next. Start pulling every connector and reseat and grease each one.

I'm always trouble shooting something as part of my job so I'm familiar with the concept. What drives me nuts with this truck is that there are no unit or circuit operation description or diagrams that I'm aware of I can use for reference. Couple that with operations I never would think of. Silly me thought that torque converter lock up was a mechanical function based on TQ rpm not controlled by the tranny.

Which begs the question, how does the tranny lock the converter in the first place. I assume it's hydaulic and goes through the center of the TQ some how.

 

well i didn't try manually locking with my temp wires.but id image if i did,the hazards wouldn't interfere with lockup cus your grounding the solenoid line to force it on.
i'll try it tomorrow.so if you need hazards while @ 35 mph or higher,you'll probably want to do the lockup mod.
for now though,id just focus on cleaning connections and get everything working the way its supposed to.

lockup is mechanical.but it's controlled electronically.the computer tells this trans what to do and when.expect for reverse and manual gear shift 1/2 i think too.

 

Ok - I opened the TPS on the IP and greased it, pulled the plug on the tranny and greased that one, and for good measure I pulled the connector on the shift lever on the left side of tranny and greased that also.

Went for a test drive. With OD off I still get 2 shifts and nothing at 35 mph. I then put the OD on and got up to about 55 mph and hit the hazard and lo and behold the rpm went up - "TQ unlocked!" I never even felt it lock up. TQ stayed unlocked until I turned the hazards off at which time the TQ locked up.

Started several runs with OD on and off to try and find where the TQ is locking up. Seems it locks up around 45 mph and not 35mph. Seems rather high to me and would certainly effect fuel economy. What do you think? Can it be adjusted by playing with the TPS on the IP? I know you can change the shift points with the TPS because I've done that but never paid any attention to the converter lock up point.

Thanks for the help fordf250hdxlt. I'm not out of the woods with this yet but it's starting to look a little better. I'll be hooking up the trailer this weekend for another test.

I have also been thinking why you might want flashers over 35 mph and then remembered I put them on anytime I'm on a grade and drop to 45mph. Happens to me often. :-) What is this manual mod you mentioned. Where do you cut into the tranny for that? Is there an instruction page somewhere?

 

i never heard of lockup accruing so high.are you certain?
now get the meter out,and ground the test lead of course,and then take the positive test lead and stick it in the center wire of the TPS (FIPL) connecter.turn the key ON but engine OFF after running the vehicle for a bit to get it up to normal operating temp (195-237 degrees) and take note of the voltage at idle,and push the throttle linkage to WOT (wide open throttle) and note this voltage reading to please.


so i did a test for ya today just to confirm.with manually locking the converter,the hazards can't interrupt lockup.
here is the best way to perform the lockup mod:
https://www.ford-trucks.com/forums/6...l#post10906711

this way you can flip the switch,and then hit your flashers and remain locked.

the best place to cut these wires and loop then into the cab,is over on the drivers side frame (real close to the MLPS sensor you stated you cleaned.) look for the wire loom that turns up and is headed for the computer,well down below the master cylinder though.if you have 4wd,she's right by the front drive shaft.but still plenty of room enough to tap into the wires fairly comfortably.
be sure to use heat shrink type butt connecters here and tuck back into the wire loom good and zip tie.you dont want to create a place for corrosion to build up years latter.

after some thinking,iv decided its a bad idea to let the converter remain locked during shifting,or at the very least,during downshifting.so this won't be anything i'll be keeping for my truck.
instead iv sent a e-mail to "ShiftSolutions" asking them if they still offer "the cure" which if i understand correctly allows unlock during shifts however locks her right back up asap instead of the stock lag time.
i think this is just what im after.
another thing i noticed is that the coast clutch can't engage (or if it does,it's trumped) when the converter is still locked.this is no good for fuel economy when im coming down the other side of the hill! so id be flipping the switch so often id be sick of it in 1 day lol.
the computer handles everything perfectly for me,just not the lockup time.

another thing,i did the brake test,and yes i can tell the lockup is still engaged and the brakes will unlock it,BUT it takes remaining on the fuel and touching the brakes at the same time to tell.
because,i believe it should unlock the convertor when you let off,while the coast clutch engages.thus the reason (and great "semi neutral state") for well.........coasting at real low rpms downhill to save otherwise wasted fuel.

 

Man tomph this thread is right up my ally. I am staying on top of this thread.

 

Sometime this truck makes me feel real stupid. OK here it goes again. Today is sat and it's a nice day. Last test was at night in the rain so driving and testing was a little tense. Anyway, I think that I can confirm that the TQ is locking up and it might be doing it somewhere between 30mph and 40mph.

It's very hard to tell because 1) it is load dependent and 2) it is so soft that if I'm not watching the tach I won't even notice the lockup.

The only way I can really tell is to put on the hazards. If it is locked and I have a some load on the drive train I will see a 150-200 rpm increase in rpm. Seems like not much difference to me. Either the converter is slipping in lock up or the tranny is very tight and has no slip. I suspect the former. In any case I don't even feel lock up anymore.

I did the volt meter test you asked for and I'm getting 1.251 idle 3.987 wot. Does that tell you anything? I think i remember 1.2 being the correct voltage for idle. Right.

I had to cut the test short when a new gremlin showed up. Has to do with the temp temp light. I'll post another thread on that after a check the forum.