My 1994 Aerostar EXT E-4WD with 149,500 km (92000 mi) has a problem with a violent clunk when moving the shifter from OD to D at highway speeds(80 km/h or 50 mph). If I press the gas harder in OD it shifts into D without a clunk. Then I can move the shifter from OD into D without a clunk, except when I do that it briefly revs up more than you would expect as if it is changing gears again. Does anyone have an idea what might be causing this?

I had a look at the transmission shifter cables. There are two of them. At the transmission side one of them is clean and shiny and moves when the shifter is moved. The other cable is rusted and looks like it never moves. Maybe it cannot move. What is that other cable for? Is it related to the problem?

 

I don't know what the cause is, but my 95 3.0L 2WD shorty does the same. When going up hills, etc. where D is preferable to OD, I either give it enough gas so it downshifts itself before moving the shift lever or let off the gas completely before downshifting.

The violent driveline buck always makes me think the transmission is about to spew parts all over the road, so I try to avoid it. So far, so good. I've got 275,000 km on the original transmission & it's still going strong.

Cheers,
Eric

 

Thanks Eric. It is nice to know I am not the only one with this problem. And the problem it is not isolated to the 4WD model since it occurs on your 2WD. So that rules out my transfer case and front drive axle. Yes mine is also very violent when it happens, and it sounds very damaging.

I would feel alot better if I knew what causes the problem. Is the problem in the transmission? Is it a shifter cable adjustment? A loose coupling? Any ideas are appreciated.

Please, if you have the same problem please let me know so I can establish a pattern.

Thanks,
Rob

 

My '91 E4WD w/4.0 has the same clunk. It's bad enough I just won't shift
out of O.D when moving. Mine also has the clunk or thump when pulling
away from a stop. Have been watching this thread hoping for some info
also.

 

The clunk is the sound of not enough revs to shift smoothly. I would start with changing the vacuum modulator on the passenger side of the tranny. It the same concept of shifting a manual without hittin the clutch, and not keep the revs high enough to keep it from grindin.

 

A new vacuum modulator will allow higher revs when using the shifter? What does the vaccum modulator do?

 

both my 3.0 2wd and 4.0 4wd thumped and thudded when shifting about on the freeway.

I have heard other board members refer to it as "hunting for gears". I call it "dammit van, cut that out!" cause it feels like my tranny is going to bust open like a piniata on jose's birthday.

my major "hunting" happens at freeway speeds, like 60-70 mph, when the pedal is pressed enough to make the tranny contemplate shifting down, but it doesnt. it kinda hops between the two gears like two girls double dutch jump-roping. ka-thud, ka tham, ka-thuid, ka-tham, ka-tham, wham wham thud. "dammit van, cut that out!"

then I floor it for a second to get the van to kick down, and everything is ok.

My buddy has had a 94 EB and his has done it since it was new. of course the dealership told him it was normal. so he took it to AAMCO and they told him the same thing.

it has to do with the gearing in the rear end, and the freeway speed, and the engine RPM. at some time the three of them dont mix well. like eating a bowl of chili and drinking a big glass of orange juice for breakfast. (ugh, dont get me started!)

anyways. thats MY experience with letting the tranny do its own thing. but if you're slamming it into drive, while on the freeway, from OverDrive, dont do that! either let off the gas and then shift down, OR get it into passing gear first by putting some weight on your right foot, then manually move it into Drive.

that will keep you from doing the ford fiesta all over the parkway.

 

mine does the clunk. what works for me is i let off the gas completly when i down shift and i get no clunk when i do this. i forget sometime to let off the gas and i get the clunk. i would think the modulator is still good if it shifts good the rest of the time.
thats my 2 cents.

 

Wow, thanks. Maybe I should just live with it.

Rob

 

my '95 3.0 shortie does the same thing. It clunks and bucks when I shift from OD to D at speeds of 40 km/h or higher. Doesn't seem to effect anything though. I'll live with it.

 

Give it enough gas to make it down shift then move the gear selector. It is a lot less shock to the drive line and I like my U-Joints.

 

bear, ive tryed what you say works for you but i still got the cluck and shake when it shifts down. the only thing that works for me is to let off the gas completly,downshift and then aply the gas again. when i do this it is always very smooth and not harsh operation. i feel no damage is happening to anything this way.

 

All Aerostars I Know Of Do This. It Is Caused By Shifting The Trans Gears While The Torque Converter Is In Locked Up Mode. If Ford Spent A Little More Money On The Electronic Shift Control Stuff It Wouldn't Do That, Or Maybe Just Recalibrating The Existing Software Would Cure It. I've Always Wished Mine Would Auto-downshift More Readily. It's An Older Automatic Design & It's A Little Sluggish Or Unresponsive At Times. Ford Saves Money On High Tech, Styling, Etc. & Then Spends It On Reliability Items. That's Why I Buy Fords-reliability. Change Your Trans Fluid Once A Year & You Shouldn't Have Any Probs. My Aero Is '94 With 195,000 Mile & Very Little Has Ever Gone Wrong. Currently I'm Looking For Urethane Rear Suspension Bushings For Mine. Doubt I'll Find Any W/o Having Them Specially Made.

 

ted, what do get from urethane rear bushings?

 

I'm Trying To Get The Rear End To Track The Front End Better, Not Taking It's Own Path. The Aero Has Too Soft Rubber Rear Bushings. Lets The Rear End Move Side To Side Too Easily. Just 'cause It's Big & Ugly It Doesn't Have To Handle Poorly. I Know I Can Make It Drive Better. I Can Find New Original Rubber Bushings Easily, But I Imagine They're All Too Soft 'cause Most All Aeros Handle Sluggishly Except Maybe Ones With Factory Towing Package Or All Wheel Drive. Also I Carry Extra Weight In Mine & Tow Too & It Can Be A Little Scarry The Way That Thing Wallows Across The Road. Just Follow One On A Highway & Notice How Hard A Time They're Having To Keep It In A Straight Line. The Back End Of Mine Moves From Yellow To White Line & Back Again Just From Small Steering Input, Sidewind, Etc. Very Unstable! Back Axle Isn't Held In Place Well Enough, But Most People Like The Soft Ride It Gives. I Use Mine More Like A Truck. NOTICE HIGH PERFORMANCE TRUCKS & CARS OFTEN USE STRONGER URETHANE BUSHINGS, THEY COME WITH LIFT KITS & HANDLING KITS, ETC.