E40D Problem

SteveBricks · #1 (**permalink**) 01-17-2008, 09:11 AM

'94 F350 7.5 E40D

30K miles on "new" rebuilt

At highway speed, the trans will occasionally "let go" and "slam" back into gear. This problem is intermittent - sometimes I can drive 40 miles with no problems, sometimes it will happen after 5 miles.

The unit is due for an oil change. Am I correct in thinking this situation goes beyond oil alone?

The oil does not smell burned, and looks pretty good.

Any thoughts or suggestions?

Mark Kovalsky · #2 (**permalink**) 01-17-2008, 11:04 AM

The Transmission Range Sensor (TRS) is failing. Replace it.

It's also called the Manual Lever Position Sensor (MLPS) or Nuetral Safety Switch (NSS.)

SteveBricks · #3 (**permalink**) 01-17-2008, 12:27 PM

Thank you Mark.

tomm211 · #4 (**permalink**) 04-26-2008, 07:17 PM

I have a '91 that does the same. We have changed all sensors and it has not fixed the problem. I would like to know if you get it fixed.

Mark Kovalsky · #5 (**permalink**) 04-27-2008, 11:09 AM

Exactly which sensors did you change?

71dusterdan · #6 (**permalink**) 04-27-2008, 11:49 AM

hey Mark can a chime in with some aod questions. got a 92 g.marquis, reverse and od are out. also nuetral with engine running will continue to pull. turn it off and i can push it back freely. are these problems that will straighten out with a complete rebuild? or do i have potential hard part problems? thank you much. Dan

Mark Kovalsky · #7 (**permalink**) 04-27-2008, 07:36 PM

Quote:

Originally Posted by 71dusterdan

are these problems that will straighten out with a complete rebuild? or do i have potential hard part problems? thank you much. Dan

Your forward clutch has failed. You need to take it apart to see what needs to be replaced.

tomm211 · #8 (**permalink**) 04-27-2008, 10:03 PM

if their is a sensor on the truck it was changed. I did find an emerecy procedure posted that would allow you to drive if the solenoid pack went out. Tried that and it worked fine. The pack and torque converter is the only thing that has not been changed.

tomm211 · #9 (**permalink**) 05-09-2008, 03:57 PM

Here is the whole story. this is a '91 e-350 ambulance. about 8 months ago while going down the high way at about 80 mph it slammed out of over drive and back in once. the more we used it the worse it got. We changed the TPS and the shift sensor on the side of the transmission, still got worse. We changed the rpm and speed sensors, no change. It seems to be very throtle position sensitive un till the trans warms up, then it gets really bad. We were thinking about changing the selinoid pack, we have another '91 next to this one, not sure if that could be the problem and not sure how to change it anyhow.