ok school me on autos

icanfixall said:

So... If the torque converter starts slipping when we let off the throttle whrer is all the heat going??? I will ask this question over on the other site. There is an ingineer that was involved in the reasearch of the E4OD before it went into the diesel trucks... Be back with an answer later....

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it does not slip. Its driven by the weight of the truck just like in a manual thats how you can get compression braking With a lock up converter it should stay locked till you hit your brakes. like mentioned above a good TC lockup test is drive with a lil bit of load and just tap the brakes you should see/feel your rpms jump up a hundred or so. The only time a TC will "slip" is when its operated under stall speed.

Alex S said:

it does not slip. Its driven by the weight of the truck just like in a manual thats how you can get compression braking With a lock up converter it should stay locked till you hit your brakes. like mentioned above a good TC lockup test is drive with a lil bit of load and just tap the brakes you should see/feel your rpms jump up a hundred or so. The only time a TC will "slip" is when its operated under stall speed.

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Cha ching!!! Winner winner chicken dinner!!

well however extremely unusefull this is does anybody know how to check the TPS

Well TCs always slip a little even above stall speed, hence the use of a clutch to lock that under cruise, but you are basically correct. Large amounts of slip only happen below stall speed.


OK!! About the neutral thing...............

The E4OD is equipped with something called a coast clutch. Normally it works as a one way power coupling that will lock when force goes from the engine to the wheels, but can be overridden when the wheels try to turn the engine (like engine breaking, for example). Think of it like the ratchet in a bicycle hub (oversimplification, but thats basically what it does). The idea is to allow the vehicle to coast better at light throttle and save a little in fuel. The 4L80E seems to have a similar function.

Now since there are still times when engine breaking is needed, the transmission has a clutch that will apply when signalled by the PCM to lock the coast clutch assembly so that power/force can be tramsmitted both ways in the powertrain. When you gear down to "1" or "2" the coast clutch will apply and prevent the truck from running away on you. Same for reverse. The PCM knows when to apply the coast clutch based on signal from the MLPS.

My truck doesn't have a stock PCM, so the behavior on the highway is a little different since I tell the transmission what it can and cannot do through programming. If I want it to neutral out I just do that manually, otherwise the TC clutch stays applied and the transmission stays in gear even when coasting at higher speeds.

93turbo_animal, I'm digging up the info on the sensor right now, hang on.......

EDIT:

OK, the FILP sensor should have 3 wires.

Black = Ground
Orange = Reference voltage (5V)
Green = throttle position voltage

Orange should have 5 volts with ignition on

Green should have aproximately 1 volt at idle, and 4 volts at full throttle. There is some discretion for where exactly you can have the settings, but go too far from that baseline and you wil have problems.

Also you want to check how smooth the change in signal is from idle position to max power position. Any spikes or dead reading zones in the sensor will cause problems in the system.

there is 3 wires going into the tps. the middle wire is where you stick in the probe on a digital multimeter. the black wire then goes to neg on battery. the key needs to be on w/o engine running. there has been a couple of threads on this and i would check to get the right numbers.

Alex S said:

it does not slip. Its driven by the weight of the truck just like in a manual thats how you can get compression braking With a lock up converter it should stay locked till you hit your brakes. like mentioned above a good TC lockup test is drive with a lil bit of load and just tap the brakes you should see/feel your rpms jump up a hundred or so. The only time a TC will "slip" is when its operated under stall speed.

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Actually, that ain't entirely correct - the torque converter will unlock every time you completely let off the throttle pedal, tis done like that so like Dave said truck can coast better. The only thing that disengages when you tap the brake pedal is your cruise control, converter lockup is done based on TPS signal.

And Gary, automatics never go in neutral, I ain't never seen one do it. To verify yours don't do it either next time you fire up your truck (or your wife's, didn't quite catch which one you're talking about) put the truck in neutral then keep your foot off the brake and put it in gear (either forward or reverse, don't matter) - truck should start moving. Then when you're at traffic light waiting for the green light and holding truck in place with the brakes, manually shift the trans from drive to neutral, you should feel the converter unloading. Then while still at that light with your foot on the brakes, shift back to drive, you should feel a slight jerk when the clutches engage and the converter loads up again. If your trans is doing anything different and you do not have a custom chip for it, the something definitely ain't right there.

93turbo_animal said:

well however extremely unusefull this is does anybody know how to check the TPS

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1) warm up engine to normal operating temperature, then shut it off
2) locate FIPL on the driver-side of the injection pump (has a 3-wire connector)
2) stick positive lead of a DVM into the FIPL's middle wire
3) connect DVM's negative lead to a good ground, preferably one of the batteries
4) turn ignition key to "run" but do NOT start the truck
5) read DVM's numbers for FIPL output voltage: idle should be 0.9-1.1V, then moving the IP lever to WOT (by hand obviously) should get you up to 3.5-4.3V
6) move the IP lever from idle to WOT and back a few times, watch the DVM's readings for anything unusual - the voltage should gradually increase as you simulate increasing throttle, any flat spots in the readings should indicate a faulty FIPL and suggest it needs replaced

M.L.S.C. said:

Actually, that ain't entirely correct - the torque converter will unlock every time you completely let off the throttle pedal, tis done like that so like Dave said truck can coast better. The only thing that disengages when you tap the brake pedal is your cruise control, converter lockup is done based on TPS signal.

.

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Ah ok interesting, I have never played with the ford E4OD but the gm transmissions I have played with, with a lock up torque converter (TH 350C, TH700r4/4l60E) have worked that way and the pedal tap is a sure way of checking for TC lockup,(I have done it) I believe its even mentioned in the GM service manual

Well TCs always slip a little even above stall speed, hence the use of a clutch to lock that under cruise, but you are basically correct. Large amounts of slip only happen below stall speed.

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lol i thought about mentioning that but i didn’t want to confuse the guy. and the clutch is also there to prevent any efficiency loss that comes with a fluid coupling (about ~ 5%)

I can't speak from direct experience, but I have heard from others that own stock E4OD driven trucks that there is a signal feed from the PCM to the break lights of the truck. This can cause problems if the wiring isn't working right (or faulty even trailer wiring) or if a bulb is burned out. I have been told that tapping the breaks will cause the TC to unlock even if the engine power is still applied.

My PCM only uses a TPS and the MLPS for signal feeds and nothing else outside of the transmission. Works well and fewer things to go wrong.

Well.... I have been schooled on the E4OD... I was wrong about my trans shifting to neutral when I let off the throttle. It "feels" like it does but its going into the coast clutch and thats why I thought it was shifting to neutral. I have gotten this information from several differant sources and I will go with it.... But it still feels like it shifts to neutral.... Thanks guys...

david85 said:

I can't speak from direct experience, but I have heard from others that own stock E4OD driven trucks that there is a signal feed from the PCM to the break lights of the truck. This can cause problems if the wiring isn't working right (or faulty even trailer wiring) or if a bulb is burned out. I have been told that tapping the breaks will cause the TC to unlock even if the engine power is still applied.

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Well, I got a stock trans, with only a pressure-riser, so all stock PCM logic and operation should still be there - when I head outta town tonight and get on the freeway I'm gonna test that, seeing how my brake lights come on well before the brakes actually engage it should be pretty easy to figure it all out.

M.L.S.C. said:

Well, I got a stock trans, with only a pressure-riser, so all stock PCM logic and operation should still be there - when I head outta town tonight and get on the freeway I'm gonna test that, seeing how my brake lights come on well before the brakes actually engage it should be pretty easy to figure it all out.

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i find the most noticeable time is when going up a slight slight hill with a little throttle pressure

Plenty of hills around Ann Arbor, will give it a shot there, thanks for the tip.

Thanks guys I'll check it out now and see whats up