I have a 91 Bronco with 302 and E4OD.

When cruising on the highway at 55-60 MPH, the trans will slip out of OD ocasionally. I doesn't happen at higher speeds. Sometimes it seems as though it partially slips out of OD (ie. RPM jumps up but not as though it went down a full gear) TC slipping? At about the same time this started happening, I started getting a loud and violent thump infrequently on upshift in other gears when going easy on the gas. Shifts smooth when heavy footed.

I have religiously flushed and replace the fluid in the trans and tc every 30,000 miles. The trans has about 140,000 miles on it.

Is there any hope for this trans? Is 140,000 all I should expect from an E4OD. Where should I start looking? TC? Rebuild? Replace?

 

I think it is the Transmission Range Sensor (TRS.) It's located on the driver's side of the transmisson, right where the shifter calbe attaches to the transmission.

As this sensor wears it can give a false reading to the transmission that you have shifted to neutral.

Get a new sensor. Installed it should cost right around $100. You can do it yourself for a lot less.

Mark

 

Thanks Mark. I'll give it a try.