Overdrive Problem

[frankgeno]

Hello. I have a 1992 Ford Ranger 4WD, auto transmission. Lately the transmission won't shift into Overdrive except on a rare occasions. The truck has 101,000 actual miles. I have had it for 18 months and it has been going into overdrive just fine until about a month ago. So I took off the transmission pan and replaced the filter and then installed the pan and added the fluid until it was full. This did not help. Any idea what I need to do? Is there some sort of an external switch for OD? Any help is appreciated. Thank you.

 

[Josh B]

How often, or how many times have you checked your fluid level since refilling it?
Also how are you sure it's level when you do, not as easy as it sounds sometimes, just askin.

Visual can too often be misleading. I began several ago to get a round level from a hardware store, just a simple half-dollar sized round level, and install it under the hood at the front. Not just slap it on but with a 4' level and the vehicle the vehicle leveled in every direction, put a big glob of silicone on the bottom of the level and press in onto the frame and let it set.
From that day onward you never again need wonder if it's level or not, just look at that bubble and rest assured you know whether or not it is, or at least, how far off it may be.

It is near pointless looking at a dipstick unless you know exactly where level is, and a transmission has a lot of floor space, so a lot of oil could be either "hiding", or "not present" no matter what it says on the stick.

I would hate to speculate as to the problem and of course it could be numerous things. Was there per chance fresh oil in it? Was there a cruddy mess in in the pan ? Was the filter the color of fresh transmission fluid or 100,000 mile TF ?
You will hopefully get some better questions and better answers in time, I certainly hope it's something simple

 

[Josh B]

Overdrive will be in the transmission, basically just a 5th gear. I don't remember now which two points it is, but either the engine and transmission, or engine and rear end are both turning one revolution each, direct drive speed, whereas overdrive will be geared to where one rotates a bit farther than the other.

It's been a while since I've much driven an automatic but do remember using things like reving it on past where it should change, and then easing up on the gas to make it settle on into high gear

 

[rusty ol ranger]

A4LD's are known to eat O/D solenoids

 

[rumblecloud]

Is it shifting okay into and out of the other gears?

Check the vacuum line. Check the shift linkage/shift cable.
There are a couple of good articles in Tech Section Here.

The OD solenoid can be replaced, but I wouldn't recommend DIY-ing it unless you know what you're doing - or even determining if that is the issue.