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Chrysler, Plymouth, and Dodge Car / Minivan Four-Speed Automatic Transmission

Transmission problems and maintenance

NONE of the following applies to eight or nine speed automatic transmissions.

This page is designed to help you to quickly and cheaply fix your "bad" Chrysler, Dodge, or Plymouth four-speed automatic transmission for front wheel drive and all wheel drive cars and minivans (we are not selling anything). This family of transmissions was released in 1989 and, with numerous improvements, continued into 2012. Here are some of the most common problems:

You can extend the life of a transmission with a transmission fluid cooler and a deeper pan. (Lauren wrote: “I was having trouble with the lockup clutch slipping on trips; with a headwind or a significant grade, the RPM would begin to edge up, and then it would get worse. I decided to try your suggestion to add an oil cooler. We then took a 650 mile trip and had no problems. What a relief!”)

A painless way to fix a "bad" transmission!

When you change your transmission fluid, always use the recommended fluid. (1989-91 owners, ignore the manual and use ATF+4).

Don't assume your mechanic or dealer knows what fluid to use. Ask them to make sure. (Some people recommend watching the mechanic pour it in. We have been told about mechanics who said they were using ATF+4 when they were not.)

All Chrysler (and Honda and Toyota) four-speed and six-speed automatic transmissions* are very sensitive to the quality of the transmission fluid. Only use ATF+4 in these transmissions. Do not use Dexron or Mercon.

People can often cure their transmission problems by changing the fluid and retraining the computer (retraining instructions are lower on the page). If you suspect they have put Dexron in*, have it replaced immediately! [if you have a 1993-95 transmission, also follow TSB-18-24-95 and get your computer updated!]

* This means Dexron III. Dexron VI might be acceptable. Jeeps with Aisin-Warner AW4/AX4 four-speed automatic transmissions do use Dexron III.

Master tech Chris Taurman wrote: “changing the fluid in 1993-95 units is a short term fix; the TCM must be flashed or replaced to prevent the fluid from becoming degraded again and to eliminate partial ‘EMCC’ torque converter clutch operation, which was the cause of 90% of torque converter shudder complaints as well as the aforementioned bump down (shift scheduling changes in the software took care of most low mileage complaints).]”

Some later models have similar situations - a computer firmware upgrade is needed.

How to check your fluid

(As per Mopar Magazine, December 2006): Put the vehicle onto a level surface, with the engine warmed up to 180° F and in Park. Clean the dipstick handle, then make sure the fluid is in the HOT region. The fluid should be in the COLD region when the fluid temperature is at 80° F. If the fluid smells burned or is contaminated with particles, have the fluid analyzed.

Chrysler four-speed automatics only use ATF+4, regardless of what the dipstick or owner's manual says. The same goes for the six-speed front-wheel-drive automatics. (At least, through 2014.)

If you don't have any problems until you have your car should mean something.

A transmission that the dealer or transmission shop says is "not repairable" can often be fixed with the simple steps outlined on this page, so don't give up hope just because a mechanic or two says your transmission needs to be replaced.


Avoid additives. Richard Widman passed us an extensive report from Chevron, which compared ATF+3 fluid with Dexron III plus various additives. They found that neither of two major brands matched ATF+3's performance specifications.

John C. Lai wrote (around 2001) that LubeGuard, used with Dexron III by AAMCO, is not a good substitute for ATF+3: "...although Lubeguard claims on their website that their product will convert Dexron to become an ATF +3 (7176E) equivalent, they have no test data to back that up. Their head engineer told me that the tests they did were conducted in the early 1990s with the first version of 7176, several years before ATF+3 was developed. So, they have no basis for their claims of ATF +3 equivalency.”

The Jeep exception

Danny noted, "The Jeep AW-4 (Aisin-Warner) transmission should use Dexron III." Greg, a DCX tech, wrote that the AW4/AX4 transmission was used on 6-cylinder Jeep Cherokees through the end of production, and on the first six-cylinder 1993 Grand Cherokees (built in 1992 and 1993), but on the Grand Cherokee it was phased out midway through the 1993 model year. This transmission requires Dexron III, while the 42RE / A500SE which replaced the Aisin-Warner transmission midway in the 1993 model year needs ATF+4. Again, if you are confused, you may just want to try one of the new universal fluids that is both Dexron and ATF+4 compatible.

Shifter issues (added July 2010)

1989 A-604Joe Kosiner wrote: There is a problem with the shifter in some 2005-07 cars (especially the LX) that causes the shifter to remain stuck in park whether you depress the brake pedal or not. A plastic part in the mechanical lockout that is tied to the brake pedal breaks and you are stuck in park. Billet Technology sells a replacement part made from aluminum, so you don't need to replace the entire shifter (as some dealers apparently do, at high cost). “Replacing the part took me about 2 hours being extremely careful about what I did. I would estimate it would take about an hour the second time around to disassemble the shifter, replace the part and reassemble. The shifter works more smoothly then it has in a long time.”

Computer revision

The 1995 technical service bulletin 18-24-95 declares that many issues (including "bump shift") can be resolved by updating the computer's flash ROM (where possible), and carefully going through a retraining process. Dealers can and should do this free of charge before any other work is undertaken (except of course for the transmission fluid change). You can also do the retraining yourself (see below).

Michael Richards wrote: “The Transmission Control Module (TCM) is another item that deserves mention. I found a TSB indicating a flash upgrade was needed to eliminate hard/erratic shift problems after 2 dealers told me I needed a $1600 transmission rebuild. I insisted they perform the upgrade first. The TCM refused to accept the upgrade so I had them replace it (they did it under protest). Now my transmission works like new. It cost $200. Something to consider.”

Solenoid packs / relays - the most common problem?

Christopher Grimm wrote that the protective screens for the hydraulic "brain" can clog; it can be taken apart (not recommended by Chrysler) and the screens and valves cleaned. Christopher recommended getting a replacement from the junkyard to work on first; he also said this only works once on any particular "brain." However, Certified Master Tech Chris Taurman wrote: “Do not take solenoid packs apart. This alters the calibration of the unit! If the filters are plugged up, replace it! The current unit costs about $150 and eliminates the need for a sound shield and separator plate!”

More often, Christopher said, the issue is simply that Chrysler and/or the rebuilder set the clearances too high, and/or the wrong fluid was used.

Step by step solenoid pack cleaning or rebuilding (with photos)

Failure after takeoff (launch)

Gary Hicks wrote: [If the transmission fails after takeoff, check] the electrical terminal that bolts into the computer housing that is mounted on the transmission. This terminal bolts on to the computer box that is below the radiator fan and mounted on the transmission; it can hold water as it did on my 1992 Plymouth Voyager. The transmission would not change gears. I used air to blow it out and the problem was solved. [I discovered it when replacing the sensors based on the advice on your site.] Webmaster note: Chrysler integrated their engine and transmission computers later in the decade.

Transmission limp mode from missing ground path

C. Wilk wrote: “1990 Plymouth Acclaim. The transmission went into limp mode. Turning the ignition on and off a few times would fix it temporarily. I added new ground wires directly from negative battery cable to one of the bolts holding the TCM to the body (new body ground) and the bolt on the alternator (new alternator ground). Problem fixed. My old ground straps looked good; I even cleaned them, and still had the problem. But adding new ground paths fixed the problem. Inexpensive and easy so try this early in your trouble-shooting.”

Use quality parts in a transmission rebuild - don't trust the repair shop!

Master Tech Bill wrote:

I have made a living doing these transmissions since 1990 and have read your page and it's great. I have dealt with aftermarket shops and also worked for dealerships. The advice I have for anyone getting their trans rebuilt is - go to the local dealer and buy a front carrier (planetary gear) and rear carrier (planet or planetary gear). Bring them to the shop and insist that they are put in. Make sure the dealer sells you the one with the hardened spline -front and the 5 pinion rear. The aftermarket is saturated with parts from Taiwan. It's like the difference between Snap-On and Harbor Freight.

If you have first release overdrive hub it has to be updated to the new hub and and also the 2-4 hub to match the front planet if the trans is made before 7/93 for the 1994 model year. The 2-4 hub breaks quite often and now has a thicker collar. Best bet-buy all four pieces if (built in) 1993 and earlier, all models if you can afford it. They have all been redesigned and strengthened.

If you get your trans done at an aftermarket shop, what you are charged for the Taiwan parts is most likely pretty close to the dealer price for the Mopar gears.

What type of fluid to use? (more details) - ATF+3 vs. ATF+4

Chrysler TSB# 21-006-01 notes that all current vehicles only use ATF+4 type 9602, part 05013457AA (for quart bottles). The advantages of ATF+4 over +3 (and Dexron for that matter) include:

You can use ATF+4 with all older Chrysler transmissions (except some Jeeps, as noted earlier, and very early automatics — before the TorqueFlite).

Rich Hutchinson wrote: [In 1989-91] both the manual and the dipstick said Dexron was okay, which is wrong. For non lockup 3 spds, either can be used. For lockup 3 spds up to some date in 1999 either could be used but ATF+3 was prefered. After that date ATF+4 is to be used in all automatics.

The best bet for transmissions made before 1998 is to just use ATF+4. Even if it's not needed, it's better than Dexron.

The Chrysler ATF+4 info center has this statement: “The previous ATF+3® was discontinued in 2005 and ATF+4® is recommended for all transmissions filled with ATF+3®.”

Remember - when you change from Dexron, also retrain the computer and "flash" the computer memory (if applicable).

Click here for notes on the differences between ATF+3 and ATF+4, and for more on addities.

Chrysler transmission filter mix-ups

The filters for the some of the Chrysler four-speed transmissions are easily mixed up, but are not interchangeable. Make sure you are using the filter specified in the owner's manual (or the correct third party equivalent). A filter which looks almost exactly the same may not work on your transmission. (Thanks, Ed Hennessy)

Retraining your Chrysler transmission

Transmission Exchange said the computer should be retrained when a rebuilt transmission is put in. This prevents both clutches from activating at the same time. Henry Traska noted that it may be best to retrain the transmission after changing the fluid if you were experiencing shifting problems.

Mark Schwieterman provided a retraining guide which applies to pre-1995 transmissions (later ones may need a dealer or transmission shop to do it, but it might also work on many later ones):

  1. Disconnect the battery to wipe the system memory clean (of course you will lose your radio presets and clock, but that's worth if it fixes the problem).
  2. Reconnect the battery [after a decent interval] and start the engine.
  3. Drive trying to maintain a constant medium throttle position as it accelerates up though all four gears (watch your tachometer). If the tranny is working correctly, you should only have to go to 45-50 mph. Do this from a standing start 15 - 20 times. You'll need a couple of miles of lightly traveled two lane.
  4. With the van below 25 mph, do 5 - 8 wide open throttle kickdowns to 1st from 2nd or 3rd. let the van run in 2nd or 3rd for at least five seconds between kickdowns and remember to kick it down from below 25. With the van above 25, do 5 - 8 part to wide open throttle kickdowns to either 2nd or 3rd from 4th. Again let the van run for at least 5 seconds in 4th between kickdowns. Kicking down from 45 or 50 mph should work.

Simply disconnecting your computer or battery for a day or so may work depending on the transmission, but valiant67 noted that, “Starting in 1995, the TCM [computer] retains its calibration even after the battery power has been removed. Since the TCM retains its memory, you must use a scan tool to reset the TCM or just let it adapt on its own.”

The "bump shift"

The bump shift may be helped by changing the transmission fluid to the correct, modern, updated fluid.

Master Tech Chris Taurman wrote:

"Bump down" is not caused by the low/reverse clutch, which is turned on prior to the speed at which bump down occurs. There are two possible issues.

Changing the transmission fluid [may work but] the computer must also be flashed or replaced [on pre-1996 models and some later models] to prevent the fluid from becoming degraded again and to eliminate partial "EMCC" TCC operation which was the cause of 90% of TCC shudder complaints (not the converter itself!) as well as bump down.

The underdrive clutch is the primary cause of all other bump down complaints (the piston seal leaks, causing the computer to command 100% duty cycle of the UD solenoid, causing harsh downshift). A rebuild is the only repair for this.

GMB3625 wrote:

The computer learns the clutch volumn indexes which tell the solenoid pack how long to keep any given solenoid open to send fluid to a clutch pack. This will only work with clutch packs that are in good shape with the right clutch clearances. If the clutch clearances are bad this will not work properly. If the seals are bad, the only way to fix this problem long-term is to overhaul the transmission.

Craig Sherman wrote an excellent guide to fixing torque converter shudder in four speed automatics.

(See “Do it yourself” guides later on this page)

Alternative repairs

Kelli Bee wrote:

I was told by the dealer that I needed a new transmission because my 1998 Neon was leaking a quart every 8 miles. The car shifted fine when it had fluid so I got two more opinions. One said new transmission, the last said there was a cut in the cooler line that no one bothered to check. I thought it was the seals, but it was easier and cheaper than that. You might want to let people know to check that.

Darrell Vines wrote: “When I had my starter solenoid worked on by local alternator shop, the mechanic asked if I had transmission problems and solved them all by plugging in a loose electrical connection.”

Bryan wrote: “I have noticed a load dependent noise at 45 to 60 mph — a bad pinion bearing. Pinion bearing failures can take years to finally ruin a transmission, so the car owner can be run around for a long time.”

Fabinator wrote: “I recommend an oil-to-air cooler with a diversion thermostat (returns oil to transmission until it’s warm). This keeps it at a constant, exact temperature, no matter what the weather.”

Rich Hutchinson wrote about the three speed automatic: “There was a programming change that burnished the torque converter clutch. Without that software the three-speed can shudder, though it's likely that normal wear could cause this burnishing and avoid the problem.”

The problem:

‘“Doing about 35mph up a small hill, when ‘click’ and the tranny disengaged. No forward, no reverse, not even a hint the tranny is even there...When I shift the lever into gear I hear the familiar faint click like it is going to go into gear, but then nothing. There is absolutely no power being transmitted to the wheels.”

A. Murphy wrote: "The torque converter splines probably sheared. I checked with the dealer and they quoted me $1,800-2,200 for a rebuilt with 3 year/36k mile warranty. Local shops quoted $1,500-1,800 with a one year warranty and they will rebuild my current tranny. I can buy a rebuild kit for $200. Add a couple hundred bucks for tools and I'm in for $400 plus tons of time."

[See the earlier tips about replacing these with updated dealer parts]

Walter wrote that the spider gear pin for the differential can go bad, but that when it does it often ruins the case. This should be taken into consideration in a rebuild (apparently Jasper has a fix for it).

Transmission gasket

fabinator wrote:

The 41TE has no gasket between the transfer plate and valve body/accumulator housing, the seal is provided by a steel separator plate. If you have harsh downshifts and gear engagements, and routine maintenance didn't solve the problem, this probably will. You have to catch this quickly.

RTV would not work. The brush-on gasket maker and high tack will probably be too soft. There is a product called "Indian head shellac" which comes in a little brown bottle, it has a cotton ball on a stick inside the cap, which is used to apply it to your workpiece. This stuff is extremely sticky, but it won't get all over the place when you apply it. Put it on the aluminum surfaces that seat on the separator plate, let it dry (it stays soft, like varnish), then slowly torque the bolts down. This will provide a positive seal that will hold up to heat, pressure, and time. I did this to correct harsh kickdowns, and it still works after three months. I inspected the shellac that was exposed to see how it held up, and it was fine. It won't come off and plug things up, ATF+4 has no solvent effect on it.

Dealing with rebuilders and repair shops

Christopher Grimm also had this advice for dealing with shops:

Do your homework. See if the shop knows about shift improvement kits for the 604. Also ask them about a wiring harness upgrade, and how they set the clearances in the tranny. See if they mention adding another clutch pack to the 1-2 clutch pack, so that there are 5 instead of 4 in there. Make sure they replace the spider gears! Above all, make sure they use the proper fluid! If not, don't even bother. If they met all the requirements except the fluid, ask them if you can supply your own.

Also see if they can get the 9" converter, costly but worth it if you want your engine to rev a little quicker. There are also different gear sets available, I have the 3:55s in mine. Make sure they set the clearances at the lowest setting possible. This will shorten the shift time, firm up the shift, and give you more life out of the tranny. An auxiliary cooler is a must!

[See the earlier tips about replacing components with updated dealer parts]

Normal noises

Dan Stern wrote (with regard to a buzzing noise just before stopping):

I can stand on any street corner in my town and in ten minutes probably hear 30-40 examples of this sound, which goes "bzzzz---zz-tic." It's completely normal. It's the transmission fluid control solenoid valves opening and shutting rapidly to make the fluid go where it's supposed to go to shift the transmission. All the FWD/AWD 4 speed automatics make this sound with every upshift, every downshift, and every gear selection. You hear the one as you pull to a stop, because the road and engine noise are minimal at this low speed.

Losing overdrive and third gear

Believe it or not, this is a sign of good design. Rather than having the engine shut down completely, Chrysler designed a "limp home mode" which causes the transmission to only use first and second, as a very visible sign that something is wrong. The immediate reaction should be checking the computer for error codes and changing the transmission fluid. If that fails, it could be a sensor problem or an internal problem. Suggestion is usually to chnage the fluid and filter (maybe flush the fluid too) and make sure that you use the correct amount of the appropriate chrysler fluid - DO NOT USE ANYONE ELSE'S FLUID!

More four-speed automatic repairs and do it yourself guides

[See the earlier tips about replacing the hubs with updated dealer parts]

Steve Knickerbocker wrote:

A rebuild kit for the A413 trans is less than $60, the book on how to rebuild them is about $20. Even if you actually bought each of the special tools specified in the book, not needed but handy, you would still come in way under $1900.

I rebuild my own transmissions and even the four-speeds aren’t hard, but they have to be spotlessly clean when you put them back together. Most of the A604 shifting issues are a clogged solenoid pack, about $60 for a new one, or an older software version which any dealer should be able to update.

Posthumous advice

Jim, the owner of Gene Poon's transmission shop, died of cancer some years ago. Jim knew his customers, and when Gene bought his used Intrepid, he first asked Jim about the status of the 604/Ultradrive. Jim assured him the early problems were solved, and Gene has been happy with his Intrepid since — but Jim sent Gene a script for customers buying new or used Chryslers. [We've shortened this notice substantially, partly due to the passage of time.]

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Dodge ambulances Mopar squads, 1980-2000

Painless ways to fix the Chrysler, Plymouth, and Dodge automatic transmissions when the break, also why repairs are needed (design flaws).