Problem and dont know what to try next

[Kris Guilbeaux]

Ok here is a problem I have come across with no luck on finding the solution.

The problem is with my Green Explorer with an A4LD. I just installed a used 4x4 A4LD into the truck for the 4x4 conversion. The transmission shifts fine into all gears with out problem. If I drive the Truck at higher speed(above 55) and after the truck has shifted into OD on coast down I get a sound I can best decribed as a dry bearing spinning fast. The sound does follow the RPMs. The sound does seam to be coming from the front of the truck and not the transmission but the transmission is the only thing I have changed.

Things I have checked:
Lose bolts
Front wheel bearing inspected and repacked
Checked all fluids trans and T-case

I did take the truck to a guy I know that knows a lot about Ford transmissions and he has never heard any thing like this on an Explorer.

Any ideas would be helpful

 

[88vert]

How long did the tranny sit before it was put in?I replaced the tranny in my Bronco2 a couple of years back and the truck that I took it out of sat for three years and it made a similar sound to what you are describing,it went away after awhile

 

[Kris Guilbeaux]

It sat for about 6 months maybe more. It was out of Fox's 94 Limited back when they started Parting it out.

 

[88vert]

Did you change the torque convertor?

 

[Kris Guilbeaux]

The Torque converter was the one out of the original Transmission which was all working fine when removed.

 

[410Fortune]

Check your belt tensioner pulley for the noise?

 

[asp84]

Kris,
The 1994 85K 4x4 A4LD (Fox's) you have sat for 6-7 months before someone bought it. (and w/o the the tailshaft adapter on it.) Although during this time, we kept the original Automatic Transmission fluid, and the original torque converter on it while it sat. The Only exposed part was the tailshaft. (exposed to the Oregon atmosphere under a tarp that is)

Concerning the irregular shifting: An A4LD has this shift pattern:

1st Gear - Torque Converter OPEN
2nd Gear: Torque Converter OPEN
3rd Gear: Torque Converter OPEN
OD Band: Torque Converter OPEN (aka: fourth gear)
OD Band: Torque Converter LOCKED (as per EEC-IV control)

The Only thing that controls the operation of the A4LD are 1-2nd shift, 2nd-3rd: Vaccumm pressure. 3-4 EEC-IV computer system. Torque Converter Lock-up: EEC-IV only. 4-3 Downshift: Kickdown cable:

Factors that control Torque Converter Lock-up operation are:
-Brake Pedal (BOO switch) unlocks TC, in expectation of increased throttle. T
-hrottle Position Sensor (TPS) When low throttle pressure detected; locks TC (apparent on Coast) and a
-Correct supply of 12V power from your Alternators voltage regulator.

So, My Question to you is: The A4LD is going in to Overdrive (right?), but unless you are coasting it wont lock the torque converter, thus dropping rpm?? Is this the scenario............. or is it not applying the Overdrive band? (meaning it is stuck in 3rd gear open which at 55mph would cause your RPMs to be over 3,100?) There is a big difference between Overdrive and the Torque converter locking up.
(Don't be confused that it is not going in to overdrive if the torque converter isn't locking up)

Before I took my A4LD out to do the Big 5.0 conversion, my A4LD was acting wierd too. Exaclty the opposite of yours actually. When I was going fast (over 55) My Torque Converter would only lock if I was giving it lots of throttle pressure. ie; if I was going up a hill, and needed to have more power, the Torque Converter would Lock-up, and decrease my rpm's doing exaclty the opposite of what it was supposed to do. As soon as I let off the gas and returned to normal cruising speed or coasting, my torque converter would unlock bouncing my rpms back up. (which again, was exaclty opposite of what is was supposed to do.) The problem turned out to be a FAULTY Throttle Position Sensor and Voltage regulator that was constantly sending 18-19 Volts to my sensors.

What I am saying is, check your computer codes (EEC-IV) using a little code scanner. Also get your manual out and check the resistance or voltage of your TPS (throttle Position sensor) at different levels of throttle pressure. Lastly, as a test also disconnect your kickdown cable fromt he transmission to see if is set to high and make sure their are no vaccumm leaks in the air hose that goes to your transmission modulator on passenger side of the tranny.

If all else fails......but only come to this conclusion after doing the above tests, it is possible that the Torque lock-up converter clutch is the problem.

Hope this helps, and Good Luck!!!!!!!!!!!!!!!!!!

Al
Good Luck......

P.S. if you check your codes and there is no "torque converter error" code, it is very possible it is an engine related input sensor. let me know if ya haver any questions.

 

[zavetsky]

This is gonna sound really dumb, but do you have auto hubs on the front??

Could it be the auto hubs failing and "ratcheting" ?? I had similar symtoms to yours and it was the right front hub spinning....

Just a thought....

 

[Kris Guilbeaux]

The Front 4x4 suspension is not in the Truck yet. it still has the 2wd front suspension. The Trans is shifting in to OD and the TC is locking up. The only time I get the sound is after the TC has locked up during driving and the truck is coasting down and at lower speeds.

 

[410Fortune]

is the converter not un locking?

You might try adjusting the kick down cable, it may not be letting the tranny shift down atthe right time while deccelleration (is that a word?)

 

[Kris Guilbeaux]

As far as I can tell it is unlocking. I pulled the Tail housing today to install the Parking pawl and the fuild that can out of the back end of the tranny came out very clear no metal shavings. I am going to drive it a bit more this week to sell if the problem still exists or if the Probelm is fading. Around town the Truck drives awsome.

 

[Kris Guilbeaux]

Well as far as I can tell all the problems are gone. After doing several things this morning and I drove the Truck on the hwy up to speeds of 65+ with out the Sound returning.

Thanks for every ones help.

 

[Kris Guilbeaux]

I was very wrong they Tranny must be toast. I drove the Truck to Houston today. It only made it there. My Very Good Friends Towed the Truck back to Victoria for me.

Let see the Tranny is banging and Popping. After the Tow ride back to Victoria. I put the Truck in reverse to get it off the trailer and all I get is a loud grinding noise.

I am Sorry to say but the Tranny is DOA.

 

[88vert]

Sorry to hear that Kris