I have a 2004 ford ranger the OD light keeps flashing but the transmission shifts good but it shifts hard in second

SOURCE: 2004 Jeep Wrangler - Clunking Noise when shifting out of Park

It could be lash in the differential which is normal, but it could also be a loose u-joint in the driveshaft. Check the rear driveshaft u-joints.

SOURCE: Transmission hesitates shifting into second and perhaps third gear when driving slow. When acceleration is positive transmission shifts smoothly. Reference "99 Mercury Transmission" as Subject when

Several things could be causing your problem:

1. Auto transmission fluid is low
2. Auto transmission fluid needs changing; this is an area that gets neglected by a lot of people;check the fluid and if its brown or gives off a burning smell, it needs changing. Very old transmission fluid will cause slipping in the transmission; if this is the case, it should be changed along with the filter

SOURCE: How do you remove the gear shift lever on a 93 ford ranger?

many of these trucks have a mazda trans in them, to remove these shifters you will need to remove the 4 phillips head screws from the corners of the trim around the shifter boot and pull it up out of your way. it's not necessary to remove the boot from the shifter, just lift it up for access to the top of the trans. at the base of the shifter on the top of the trans you will see a plate attached with torx head screws. remove all but 2 of them, now make sure the trans is in neutral and remove the last 2 screws and pull the shifter straight up. the shifter is now out leaving a big hole open on the top of the trans for dirt to fal into so put a wrag in it or screw a piece of cardboard to it. installation is the reverse. good luck

SOURCE: 97 ford contour, 2.5 L, automatic transmission, OD

The first thing you need to do is get the tranny power flushed.
And not the aerosol cans of flush you buy at the parts store.

Don't go to AAMCO either.

Certified transmission or a reputible service garage can do this. It averages about $160. The contour uses a CD4E series automatic 4 spd tranny. It has a history of overheating. It was used in the Contour, Mystique, Ford Escape, Ford Probe, Merc. Cougar, Mazda 626 and MX-6, and Mazda Tribute. all had the overheating problem that cooked the tranny fluid. They run hot.

The overdrive light starts blinking I bet when you drive it on the interstate at highway speeds for about 5 or more miles... then it shifts real hard (whiplash effect). Turn the car off and reset the transmission controller and the light stops, and it shifts normally... this doesn't fix the problem though.

Primary solution is to flush the tranny. You have to do this to save whatever life is left in the transmission clutch disk/packs.
The CD4E does not have a filter in the pan, but a screen. It's located on the front of the transmission, not the bottom. The pan is hard to get at and is easier to do if you remove the tranny from the car. .

As i said, have the tranny flushed, then, pick up a good "stacked fin" oil cooler from your parts store. They run about $70 for a good one. If you get the tube/fin ones, they average about $30 but only cool half as much for the area they take up.
You can get a used one out of the early model ford Explorers (92-94) with automatic transmissions. They run about $5 to $10 at the junk yard.

Find the Transmission cooling lines going into the radiator tank and using a mini pipe cutter, cut the return line that goes from the radiator back to the transmission about 6-12 inches back from the tank. Get some heavy duty rubber oil tubing from your auto parts store and divert the output line to the cooler and then back to the tubing that hooks to the transmission...
You can even add an externally mounted oil filter, like the one used for the engine, next to the cooler giving you a great way to maintain your transmission even longer. A filter you can change like your oil filter.

Either way, you'll cool the fluid properly and extend the life of your transmission. The blinking light is a warning, like your check engine light, to get you to check the transmission... ie... I'm running too hot!!!
Also, here's a web site with photo's on how to do this....
http://www.grandprix.net/upgrades/cooler.html

one more...
http://images.google.com/imgres?imgurl=http://i.ehow.com/images/GlobalPhoto/Articles/5091022/229127-main_Full.jpg&imgrefurl=http://www.ehow.com/about_5091022_transmission-cooler.html&usg=__8xUKBwqIDsrAYI8cMhg5Uw8bHs4=&h=450&w=600&sz=40&hl=en&start=4&um=1&tbnid=6HnuKpt_YA78IM:&tbnh=101&tbnw=135&prev=/images%3Fq%3Dexternal%2Btransmission%2Bcooler%26hl%3Den%26sa%3DN%26um%3D1

joecoolvette

• 5660 Answers
• Posted on Oct 31, 2009

SOURCE: Ford ranger, getting harder to shift into gear

Suggest you check the fluid level of the transmission first. Remove the fill plug, and see if it is Below the proper level. Do Not fill at this time! There is a reason for this.

Then I would suggest draining the fluid. You are also looking for brass fragments in the fluid. Drain into a three quart metal, or plastic drain pan. (They are approximately 18 inches across, and 4 inches deep)

1.Manual transmissions use Synchronizer's made of a brass alloy. The synchronizers have tapered teeth, that the nose of the teeth can be worn down. Also a tapered surface on the synchronizer, that can be worn down. Brass fragments in the transmission fluid is a sign of this wear.

Some brass 'dust' will occur as normal wear. A large accumulation means you have problems. Transmission is hard to shift, is one of those symptoms due to this.

This link to an animated working of a five-speed manual transmission, may help to explain how the components interact with each other, and also help me to explain the Synchronizer/s.
(From Howstuffworks.com - Auto- Under the Hood - Transmissions and Drivetrain)

http://auto.howstuffworks.com/transmission3.htm

Looking at the animation, observe the 'gold' colored parts. In particular, observe the the pair of gold colored teeth at the rear. (The teeth are in a vertical row, going up and down)

Now also observe the blue colored teeth next to them, on either side. (On the spinning gears)
You are looking at a side view of the transmission, and also a side view of the Synchronizers.

The synchronizers are round just like the gears. They have a Female tapered surface where they meet the gear. The gear has a Male tapered surface on the outside of the gear, that matches.

When the female tapered surface of the synchronizer meets the male tapered surface of the gear, the friction contact makes the synchronizer start turning the same speed, as the gear.

Helps the gear being shifted into start turning also, and the - teeth of the synchronizer, - gear to be engaged, and - already turning components are synchronized to each other. They will be all turning the same speed, so shifting will be smooth.

This shows you Synchronizer rings for a 4-speed Muncie transmission,

http://cgi.ebay.com/ebaymotors/MUNCIE-4-SPEED-BRASS-SYNCHRONIZER-RINGS-1963-TO-1974_W0QQitemZ360137693405QQcmdZViewItem?rvr_id=&itemid=360137693405

Enlarge it for a better view.
See the teeth going around the synchronizer ring? Notice that they are pointed, or V shaped. When the nose, or tip of this V is worn down, a manual transmission is hard to shift.

Also observe the flat landing on top. (In this view it's on top) The flat landing has three rectangular cutouts in it. (There are used for Detents)

Come from that top landing, down the side to the teeth. This Side has a tapered surface. Tapered ever so slightly, that it is not readily visible in this photo.
When this tapered surface wears down, the transmission is hard to shift.

Summation?
1.Low fluid will cause hard shifting. It will also cause abnormally high wear of the synchronizer rings, (Synchronizer Rings are also referred to as 'Blocker Rings')

2.Worn Synchronizer Rings,
Broken or worn Detent 'buttons',
Broken Detent Springs,
and worn Synchronizer Hub's,
will cause hard shifting.

Should you not have an abnormal amount of brass shavings in your transmission fluid, and found the fluid to be low, you may want to just replace the fluid to the proper level, and see if this works first.

If so, I suggest contacting your Ford dealer, and see what the proper transmission fluid is for YOUR Ford Ranger. They will go by THE transmission is used in your truck, and will have any updates if better fluid has been developed since your truck was made.

I know dealers are expensive to buy from sometimes, but I implore you to use the transmission fluid they recommend.
It will have special additives.