'96 explorer control trac, 4x4 and transmission trouble !

Hello again.

At the begining, the car didn't shift the 4th gear (overdrive - as i heard), and between the second and the third, there was a short delay, which came out with the engine rpm going up from 2000 to 3500 and the shift. Also, while keping the throttle constant, you could feel a repeated bump in the floor.
I had the transmission overhauled, changed a pinion whih was dmaged, all seals and bearings, etc, plus oil and filter.
AT THE BEGININGS, EVEN THOUGH THE TRANSMISSION DIDN'T SHIFT INTO OVERDRIVE, I HAD NO LIGHTS COMMING UP, AND NO ERROR CODES.

After haveing the tranny overhauled, the first long trip i took, after about 100 miles, the tranny started to shift erraticly. after a few hours, i got back on the road, and it was doing fine.
Then again, when driving a long trip the same thing, but this time o/d off light started to blink.
I NEVER GET ERRATIC SHIFTS OR O/D LIGHT BLINK WHILE DRIVING IN TOWN.

Can this be because of the tranny? More accurately, can it be because of the valve body?(or shift solenoids?)

2. Another problem i have is that bump in the floor that never left me. It was there before, and is still there. They told me to change everything : fuel filter, spark plugs, spark plug wires, maf sensor, air filter, etc. Nothing. the bump is still there.
I took the car to a local ford shop, to do a scan, and nothing came out. Ignition timing ok, fuel pressure ok, injector status ok, engine missfire ok, everything ok. But stiil bumping. (the bump feels like a misfire, but it's not)
They say that it may be the fuel pump.

However, when i put the car into Auto 4WD, the bump doesn't come up. The car runs perfecly. Anyone knows for what reason this happens?

3. And finally, while in 4wd AUTO mode, on slippery surfaces, there is a loud bang in the back when wheels loose traction. Is that normal? It feels like the 4wd couples and de-couples. I heard that this may be normal, due to the type of limited slip differential installed on my model. But however, is this normal? Or there is something wrong with the transfer case?

PLEASE HELP ME!!! WHAT A HELL IS WRONG WITH THIS TRUCK? SHOULD I THROW IT INTO THE SEA? THX :banghead: :banghead: :banghead:

worry no more!

i had ther same problem with my 96 explorer....fix it now, you might as well b4 it gets worse. i had to replace all the small parts of the tranny and get a new torque converter...then there was still something wrong with it. so i brought it back and they ripped the tranny apart and found what it was...never told me though lol.
id say take it to a tranny guy or get one reccommended to you by your mechanic and stress to them every problem you have...if they have the time YOU take THEM for a test drive and point out the problem...
its a gauranteed fix. -for the tranny atleast...yur bump i dont know about...but there is much life left on the car

thx man. i also changed the small parts, including one big pinion. now the tranny works fine, except for the long trips :), so the drive test is kind of impossible. no mechanic would drive 100 miles with me to find out what the sympthoms are :)
however i'm planning to change everything (torque converter, valve body including shift solenoids, transfer case) and if it still runs like this, i'll crash it into a wall or something.
Open for any other sugestions :screwy:

Hello again.

However, when i put the car into Auto 4WD, the bump doesn't come up. The car runs perfecly. Anyone knows for what reason this happens?

3. And finally, while in 4wd AUTO mode, on slippery surfaces, there is a loud bang in the back when wheels loose traction. Is that normal? It feels like the 4wd couples and de-couples. I heard that this may be normal, due to the type of limited slip differential installed on my model. But however, is this normal? Or there is something wrong with the transfer case?




Ok, I am a little confused here. When you are driving on a hard dry road, you should ONLY drive in AUTO 4WD. Your other choices are 4W HI and 4W LO, which are NEVER used on paved dry roads.

Auto 4wd lets the clutch pack in the transfer case slip and relieve the tension buildup between the front drivetrain and rear drivetrain that occurs in ALL 4wd vehicles. If you drive in 4W HI, the clutch pack in the transfer case locks up, which engages the front wheel drive 100%. If you then drive on a dry paved road, the tension buildup between the two drivetrains will ultimately be released when the tension FORCES the clutch pack to slip. This is your BANG or BUMP. 4W HI and 4W LO are for icy, or dirt roads only - on these roads the tires can slip enough on the ice/dirt to relieve the drivetrain tension. You can damage the transfer case by driving in 4W HI on dry pavement, as well as other drivetrain parts.

There are sensors on the front and rear driveshafts that sense the speed of the driveshafts. When the rear spins faster than the front, and you are in AUTO 4WD, the contol trac system engages the front wheel drive by engaging the clutch packs in the transfer case. The clutch packs can be engaged from somewhere around 10% up to 100% ( which is the same as 4W HI). The bang you are hearing here probably is the clutch packs engaging.

I would suggest you put fresh high quality fluid in your transfer case - not the cheap stuff. If your old fluid comes out black, change it TWICE. Also, remove and clean your driveshaft sensors - try to get any rust off the driveshaft where the sensors are. This should help the banging somewhat.

BUT, If the bang you get as the 4 wheel engages on ice when the rear wheels slip is clearly from a different place in the truck, then put the truck on a lift and check your u-joints and lubricate the slip joint on your rear driveshft. You cannot correctly check your u-joints with the rear wheels on the ground.

Rear differentials usually whine if they are having problems, so I don't think you have a problem there, but it won't hurt if you also put fresh fluid in the rear diff.

That should get rid of the bumps and bangs for the most part. You can still get some bangs from the transfer case if your rear wheels slip suddenly and your rear tires are spinning fast before the front wheel drive engages.

As to your transmission, I have heard of people rebuilding trannys in the Explorers because of erratic shifts, only to find that the digital tranny range sensor was bad or out of adjustment. Before you go wild on the tranny, you may want to replace the range sensor and make sure it is properly adjusted. Can't guarantee thats your problem, but it may be worth a try.

Thx for your post. In 4wd LOW i don't get any bumps. I only get this in 2WD mode. I understand that the bang in 4WD AUTO is because of the limited slip diff.

People says that the bump ma come out because of one of the ignition components (spark plugs, spark plug wires, fuel lfilter or fuel pump, and even injectors) Is it possible?

However i wil change both transfer case and diffs oil.
As for the tranny, where is that sensor located? on the gearbox or somwhere else? Thx. And besides that, how can it be adjusted? Manually or with a diagnostic tool (as ford shop have)?

THX :frown: