new transmission in my dads truck, whats wrong???

[SPR1NK]

ok, my dads truck is a 93 7.3 with the E40D transmission, he has been having some trouble with it not shifting, and after talking to some mechanics he knows he decided to put a brand new torque converter and transmission in. as he works out of town he had me put the new transmission in. finally got it all in today and took it for a drive and it will drive just fine if I put the selector in 1st, 2nd or reverse but if it is in drive it will not shift up out of 1st and once the rpms get high if you let off the throttle and then push the throttle again it acts like it it is in neutral until the truck slows down again. then it acts like its in 1st gear again.

after seeing this issue I called him and told him about it and he told me it was exactly what it was doing with the old transmission, so I am at a loss as to what the problem could be.

 

[FORDF250HDXLT]

i have some good news and some bad news.the bad news is really bad and the good is really good.


the bad news is,the old transmission is fine.he bought a reman needlessly.

the good news is,the trouble is very easy and inexpensive to fix.he needs a new range sensor (formerly known as MLPS)
it's the large sensor,located on the drivers side of the transmission,under the shift linkage.

it does suck,cus when this particular sensor goes,you'd swear the trans is shot.after all how else can a trans just slip into neutral on it's own,not upshift and then even bang into gear if everything is mechanically sound right? ah, but that's the joys of electronically controlled devises.always start with the simple things first.it's human nature to jump to the worst case scenario though.

whats worse is,these e4od controllers in the idi trucks don't toss the range sensor/mlps code very often when this happens so no flashing od light when we need it the most!
it's important (vital really) to know the symptoms of a failing range sensor with these trucks so "we won't get fooled again".

 

[SPR1NK]

He did have that replaced before he bought the transmission
They told him something about reprogramming the sensor with the computer when they put it on(I have no idea who did it or what they were talking about) and after that he still had a shifting problem

 

[FORDF250HDXLT]

maybe it just needs to be adjusted.you'll see a line that needs to be lined up with a slot while the trans is shifted in the N position on the sensor.take a look at it.set the e-brake/chock the wheels before getting under the truck with it shifted in N.
you'll need to remove the shift linkage before you can see the lines.take the nut off and then wiggle it towards ya.

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[SPR1NK]

How do you adjust it?
Just loosen the books that hold it in place and twist it or something?

 

[icanfixall]

Yes its just that easy as loosening the 2 bolts. Then line up the marks. Tighten the bolts and test drive it.
Another place to check is the throttle position senser. Its located on the drivers side of the injection pump. It has 3 wires going to it. It MUST SHOW between .96 to 1.2 volts on a warmed up engine. Key turned on but engine off. The center green wire is where this voltage will be measured. Usually the tps switches are replaced around 70,000 miles. They wear out. What I do is use my dicital voltmeter with the pin ends. Ground the meter to the battery and push the sharp pin positive end into the green wire. Reason the engine needs to be warmed up is that way the fast idle wont be holding the throttle open to run a fast engine for warm ups. Easy to adjust. Simply loosen the bolts or screws.The rotate the switch till you see the voltage you want. Lower voltage makes a soft shift. Higher voltage makes a firmer shift. Wide open throttle should never see 5 volts. Thats shorts out the computer that controls the trans and you end up VERY hard shifts that will break your neck.

 

[SPR1NK]

Ok good to know
I will try to adjust the shift lever sensor and check the throttle sensor tomorrow

I know my dad has never replaced the throttle sensor in his truck drive he got it and he had had it for a good ten years at least so it's probably due for replacement,

 

[Mikey89014]

Could also be a bad speed sensor and TPS.

 

[SPR1NK]

Speed sensor?

Where is that at?

 

[79jasper]

Speed sensor?

Where is that at?

Rear axle.

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[trackspeeder]

The range sensor doesn't need any programming. Set it, then plug it in.

I would replace the TPS because its old.

Check the TCM for power. The TCM relay is under the hood.

I usually would say this first. Check for codes.

 

[SPR1NK]

Checked the tps a little while ago, couldn't even get .9 volts out of it no matter where I adjusted it to, highest I saw was .85 new one will be here tomorrow

Where exactly is the tcm located?

I put our code reader on it yesterday and got DCT 14 and DCT 67 (sorry forgot to put that in OP)

 

[SPR1NK]

Oh, also any way to check the speed sensor? Or is that just a replace and see if it works kinda thing?

Did also check the MLPS adjustment today and the lines are lined up

 

[icanfixall]

Funny that you could not get the correct voltage from the tps. Remember the engine warmed up. Key turned on but engine off.. Not running. then ground the voltmeter to the battery ground and the positive to the green center wire at th tps. Open up the throttle to see if voltage climbs. Its supposed to increase but will never reach 5 volts.
Now a cautuion of installing the new tps. Feel how the old one comes off the drive tab. the new one MUST fit that tab exactly the same. Look at it when it comes off for wear or rusty marks. Then install by winding the new one of that tab. I replaced those screws that holds the bracket to the injection pump with 1/4x20 bolts. then a 7/16 combo wrench is easily used to tighten or loosen them for adjustments.

 

[SPR1NK]

Engine was warmed up(I had test drove it again just before looking at tps) and I did have my multimeter grounded to the battery and stuck into the green wire
Tried moving it all the way in both directions and never could get higher than .85, at the spot where it got .85 I put it to WOT and got 1.8

Winding the new one? Not sure what you mean