Hello, my F250 460 1995 with E4OD transmission has a problem. 4 weeks ago I overhauled the engine a bit and installed a new gearbox from the USA because the engine was always off immediately when D and R were engaged. With new gearbox, now I have the same problem again. Here in the forum was once a report on the same problem. I can not find it anywhere. Who can help me with tips? The brake is also too soft and the pedal can be pushed too far. The brake booster has already been replaced, the brake fluid exchanged and already vented several times. The vacuum hoses are all good and build up negative pressure. Is there an electronic component somewhere, which sops the engine? Please help.

 

Just a thought but maybe the convertor is stuck in lockup.

 

Did you change the TR sensor?
Did you change the TC?

I have a switch to make my TC locked up so it will do that if someone tries to steal it.
I also use the switch going down hill to keep the clutch engaged.

 

Typically if the engine dies as soon as you put it into Reverse or Drive, it means the torque converter clutch is being applied. Did you change the torque converter when you put the new transmission in?

If you did, I would suspect your issue is either a failed computer, or a damaged wiring harness with a short to ground, causing the converter clutch to be applied. As a test, disconnect both electrical connections from the transmission and see if it still dies when you put it into R or D.

 

Thank's for answers to all.
Yes, the TC is new with the transmission and I changed the TR sensor. The TR sensor I bought it by Rockauto.
I try the test tomorrow morning.

 

If I read this right you had the same problem before changing the TC and the transmission.
So you either have a harness wire shorted to ground or a bad PCM.
I vote for a bad wire shorted to ground.
This has came up before on this site.

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You are saying that if you let the truck start moving, it doesn't die? That's a classic symptom of the torque converter clutch being stuck applied.

Your soft brake pedal problem can be a number of things. I'd start by making sure the rear drum brakes are properly adjusted. If the soft rubber brake hoses (going to the rear axle, and to each front caliper) are original, I'd also replace those. Also make sure you properly bleed air out of the the ABS module. If that does not fix your issue, the only two possible culprits left are the ABS module, or the brake master cylinder.

 

the master cylinder was also exchanged for a new one

 

Today I have both plugs removed from the gearbox and it is the same problem. Then I took the brake booster from the vacuum and sealed, only if I step very firmly on the brake, the engine keeps running ...

 

Are both plugs removed from the gearbox when you step very firmly on the brake and it keeps running?

 

Did you use the old solenoid pack?

 

Huge vacuum leak in the brake booster may solve both questions.

 

a new one from Rockauto

 

How about taking a moment to prove or disprove the act of applying the brakes has anything to do with the issue.
You stated both light pressure and then later that heavy pressure on the brake pedal allowed the engine to stay running. That said you had some changes that might very well be the reason for that.

Brake-shift interlock switch prevents moving the shift lever into gear (out of park) without pushing the brake pedal down first. The act of in turn activates the brake light switch, creating a vacuum demand, flexing metal, pinching wires etc etc.

To a high degree you can bypass all those possibilities by,

Block the wheels so as the truck can't move either direction.
Turn the key one click toward "run".
Move the shift lever to "neutral"
Turn the key to start starting the engine.
Do not press the brake pedal at any time during the above process, the act gets around the Brake-shift interlock allowing you to shift into forward and reverse and the brake pedal not having anything to do with it.

Engine hopefully running at this point, try giving it a little throttle see if it will attempt to move forward and reverse without issue.

Myself I'd do this test with the connectors for the transmission plugged in. I'd do that and then based on result of the test decide if want to try again but with the range selector connector unplugged. And then based on result of that test, I'd do so again with the solenoid pack unplugged. Keeping in mind for a test without power to the pack, result to fourth gear IIRC.

Combination of tests should/might help narrow down where the cause of the problem originates.

Keep in mind that anytime you return the shift lever back into "park", you gotta go through that same process again to bypass the Brake-shift interlock. So you can start and shift the truck, see if it will run and move and without having to press the brake pedal to do it.

Any and all of the suggestions so far tend to assume the engine runs good, that it runs strong enough to maintain a good strong idle speed in and out of gear if no other problems existed.