Ugh...Tranny problem or something

[jamessavage]

Ok, so my 2000 5.o EB and I were headed home the other day and at 70mph something crazy happened. My RPMs went up, O/D kicked out and my "OD Off" light started blinking. I managed to get it home but it was a strange ride. The shift RPMs were way off. I can't say exactly but they were really high and very hard shifting. Curiously, I happen to have a cracked passenger side exhaust manifold and the noise coming from there was intermittently much quieter.

I got it home and my fluid level checks out. I'm at a loss. I'm reluctant to take it to a garage to have them charge me a bunch of cash to tell me it's junk and it's not worth the cost of a tranny anyway.

Any thoughts on where to start? No P codes and I can't read the tranny codes but if theres something little I should be looking at I'd appreciate anyone that might point me in the right direction.

Thanks,

Jim

 

[gmanpaint]

You need the trans codes read. It went into safe mode.

You can drive a short distance in safe mode, but keep it under 50 miles. If you need to go further, disconnect the battery and wait 15 mins or so, then reconnect it. This should kick it out of safe mode temporarily, but might come back on shortly. Tow it into a shop that can read trans codes if need be, for a proper diagnosis.

 

[sot]

explorer won't move and yet cranks right up when running a rattling sound is coming from the transmission. Can the flex plate break away from the torque converter and cause this problem?

 

[jamessavage]

So I took it to the garage I use for stuff I can't fix myself. They don't do tranny work but scanned it and came up with

p0455- evap major leak

p0713-which he said was "Tranny fluid temp -40"

p1270-Excessive RPM/vehicle speed.

He "reset" the codes and it ran better but is still hammering 4th gear and th OD light is still blinking.

I figure I'll do fluid and filter but I'm up for any further ideas. I really don't want to replace this thing. I does have 250k+ miles but I don't really want to start making payments again.

 

[shadowless127]

that p0455 is probably a rusting fuel filler neck.

Sounds like your transmission and torque converter are shot. In 2011 I replaced my trans with a JY one for $900 including labor. $400 for a transmission with 78K miles, and $500 to have the transmission shop replace it, change the fluid, change the filter, and change the pan gasket.

 

[gmanpaint]

If the rig is in good condition, I would always think of replacing a bad Trans, by rebuilding the one I have. A rebuilt Trans will give me more peace of mind, over one of unknown origin.

If the rig is in poor to fair condition, you might think of looking for a replacement. 2nd Gens are pretty affordable these days.

 

[jamessavage]

It's in fair condition but facts are facts...the 4r70w in it was rebuilt about 60k miles ago and the value of a new or rebuilt transmission exceeds the value of the 'splorer. I was hoping there was some kind of better news but it looks like Ima have to get something else.

 

[my98nnj]

P0713 - Trans fluid temp. Obviously it's not reporting the correct temperature and might be causing the odd behavior. Find and replace that sensor, it's probably accessible after dropping the pan.

 

[jamessavage]

OK. I've looked and searched and come up with a faulty transmission fluid temperature sensor being the likely culprit. If faulty it will create shifting issues, thus causing the engine to be over RPM/speed and setting the other code. Problem is, I can't find a listed part. Every other year with the 4r70w transmission says it takes F1DZ-7H141A (I believe) but when I look under 2000 Explorer 5.0 I get nada.

I'm trying like hell to get the parts together before I drop the pan and make a big mess. Anyone able to confirm the actual part number? Someone must have dealt with this in the past or have more knowledge than I do here.

Thanks.

Hehe, nods to my98nnj... read your reply after posting mine.

 

[jamessavage]

Well, I figured out where the TFT was (in the wiring harness) in case anyone runs into this in the future. Replaced the harness and nothing changed. I'm still screwing with it since I can't afford to replace it yet...might as well tinker with it and try to figure it out. What I've read is still suggesting a fault in the PCM to TFT circuit. It's impossible for me to really know unless I hook it to a big boy machine (which I don't have) and read the activity as it happens so I grabbed my handy dandy meter. Now I'm wondering if anyone knows where I can find a pin test sequence for the TFT circuit. Just to reiterate, It's a 2000 Explorer 5.0 with 4R70W transmission. I'm hoping I can find a bad connection or open circuit and fix that.

Thanks in advance for the assist!

 

[1998Exp]

If your 2000 is anything like my 98, it will be pin 37 of the PCM connector (second row from the top, 11th position counting from the left). The wire should be orange with black stripe. Note that there is an inline connector (C116) between the transmission and the PCM. This is a large, square block located at the firewall, not far from the PCM. On this connector it's pin 30 - second from left on the second row from the top, looking into the female part.

Now I'm wondering if anyone knows where I can find a pin test sequence for the TFT circuit. Just to reiterate, It's a 2000 Explorer 5.0 with 4R70W transmission. I'm hoping I can find a bad connection or open circuit and fix that.

Thanks in advance for the assist!