Engine/Transmission (1994 - 1998) '97 auto acts like it's low on fluid

[masterstream]

Tried to diagnose this by searching w/o any luck. Only found brief mentions of TPS, sensor and solenoid problems as possible culprits.



A year or more ago my transmission began to develop a funny 1-2 shift. It normally happens shortly after startup when the air and the engine are cold and is more frequent when the 1-2 shift occurrs in a left-hand turn. The engine revs without power to the driveline for a second and then it "catches" and resumes normal operation. The problem has gotten progressively worse and the transmission has begun to exhibit a hitch when accelerating after a few minutes of idling in drive such as at a stoplight. Again, no power to the driveline and then an little bump followed by normal operation. This problem happens erratically, no matter the temp of the air and engine. Now, the transmission will work normally, at idle in drive (like you're easing through a parking lot looking for an empty space) when it suddenly acts just like you've placed the gear selector in neutral for a few seconds. It exhibits the same behavior in reverse. As with the other problems, after a few seconds, the transmission resumes normal operation. The fluid level is right on the mark (warm engine running in neutral) and the transmission pulls as strong as it ever did under heavy throttle or at cruise speeds.



I have a BD TC and Transgo TFOD-HD2 shift kit that have been installed for the last 130,000 miles.



A friend with a '98 CTD and another with a '98 gasser have similar problems with stock transmissions.



Any ideas?

 

[KennethS]

Mine did the same thing mine was a 95

When cold weather came my transmission did not like It at all. It had to reach operating temp before It would work like It should. At first this scared me and thought It was going bad but after talking to a transmission man and he told me that was normal I just put up with It. This summer I took the Dodge to Dave out IN Iowa and he rebuilt the trans and now It works like It should have IN the first place. What a difference even the overdrive Is different and now a dream to drive. I guess you will half to put up with It or else do what I did.

 

[JoshPeters]

Change your Fluid and filter. If the filter gets a little debris in it, which is normal... . it can give you flow issues when it's cold out.



Josh

 

[masterstream]

I don't think this is a problem that will be fixed with a fluid and filter change. I bought the truck new in late '96 and the transmission worked flawlessly for years, handling ~300 horsepower. The fluid and filter, including what's in the TC are changed every other Spring, or about 25,000 miles. Something has happened to create this problem in the past year or so.



Come on guys, I need some more ideas. I've been able to fix every problem I've ever had by getting info from you on this site--don't end the streak!

 

[JoshPeters]

My trans does that every time the filter needs to be changed. I've been told by Many trans guys to change the fluid/filter every 15,000 miles.



The funny 1/2 shift could be a band adjustment. 1st stays applied, then the 2nd gear band applies.



You could hook up a transmission pressure guage and see what your pressures are. You may very well have an issue there.



The parking lot issues and release/apply at random low speeds does kind of sound like a torn/worn seal.



Josh

 

[biggy238]

What did you find out about the TPS? It sounds to me like a dead spot in the TPS.



Mine was bad and would lock the transmission and TC after sitting at a light or in a parking lot... It could have the opposite affect I suppose, by not letting line pressure come up.



"The only man alive to greenhorn an automatic"

Kyle

 

[Extreme1]

I agree with Josh, 15,000 mile fluid and filter changes are critical on these especially when the power is increased. The problem at idle isn't from the TPS, a bad trans electrical part or a loose band, it seems the fluid isn't getting through.



I overfill my trans up to the bend in the dipstick above the full level. It isn't enough to get the fluid to foam and the only problem you'll have is if the seal where the dipstick tube goes into the trany leaks, a luttle fluid might come out there. Minor.



A pressure check will help diagnose this.

 

[JoshPeters]

The other thing I thought of was the Gov pressure sensor. If that is reading improperly, mine would downshift to far on a low/mid speed corner making me think it would go to neutral.



Just another thing to check.

Josh

 

[Dieseldemon]

Filter and fluid first

 

[JoeMartin]

Power Flush the system. Mine did this when I first got it a year or so ago No I have an Rh and yours should be an RE but basically the same design. I promptly dropped the pan and did a fluid and filter change on it and about a week later it started again.

Naturely I thought it was the end of the transmission, after talking to a few trans people that I know someone suggested a power flush of the system. Having been said already in this thread a little debris is normal in the trans what happens is the Cooler begins to get clogged and the result is a preasure drop. I had mine Powerflushed and the problem has been gone for almost a year and 25,000 mile.

One word of caution in powerflushing tho, Make sure you find a shop that does not use a recycle system, you want it powerflushed with constant new fluid not the same stuff over and over. JiffyLube did mine and it took 22 qts to flush but was well worth it.

Just another thought.

 

[Lsfarm]

Low Fluid

Your transmission does not know if it is going around a turn, only the ATF feels the sideways forces. If there is too little ATF, then the filter goes dry and the pump sucks air, the pressures drop and the rear clutch releases. Which is Neutral.



The dipstick is difficult to read correctly, read BOTH sides of the dipstick and use the lowest reading. The higher reading is from the dipstick tube touching the stick.



With a stock pan, often if the ATF level is in the 'safe' range it is still too low. Keep the fluid at the top or even 1/8th to 1/4" above the full mark. This is NOT too high a level to allow the ATF to touch the spinning clutch drums in the trans. It will not foam.



Or just add a MagHyTec deep pan and this will give you lots of extra fluid above the filter level.



I've seen this many, many times with the stock trans pan, it has marginal capacity at best when the fluid level is at max on the stick.



Hope this helps, Greg L

 

[masterstream]

Alright, you talked me into it. As soon as we get a reasonably warm day here, I'll change the fluid and filter and overfill the pan. Lsfarm, how does a MagHyTec place the filter deeper in fluid? I envision the top of the MagHyTec being in the same place as the stock pan and fluid being deeper BELOW the filter. Thanks for the help.

 

[Lsfarm]

Deep pan

If you install a MagHytec deep pan, there is an aluminum block that is installed between the valvebody and the filter. This drops the filter to the bottom of the pan.



If you install a standard depth MagHytec pan, there is more ATF, and there are ridges or baffles on the inside of the pan to restrict the ATF from sloshing around as much. But there is not a spacer for the filter.



Since you are going to change the filter and ATF anyway, take several readings of the ATF level, and add enough ATF to bring the level to 1/8" to 1/4" over the full mark and drive it to see if that is the problem. If it doesn't change anything then you can look closely at the filter when you drop the pan.



It's possible that the filter is not screwed securely to the valvebody and there is a gap allowing air to get in after the filter.



Let us know what you find. LsFarm

 

[Skydiver]

I had a power flush done. Then I knocked the check valve (ball) out of the cooler line. The trans now shifts normal when cold instead of winding out the engine. Everything is still stock.

Tim

 

[biggy238]

Tim, could you elaborate on how to do this? My 96 hangs 2nd what seems like forever sometimes.

 

[Skydiver]

I think the power flush alone took care of the slow shifting problem. The check ball is hard to get to. It's behind the oil cooler on right side of engine. Short hose about 1 foot long. Put the oil line in a vise and use hard piece of steel to knock it out.

If you are going to do a power flush make sure they change the filter first. Some service men do not change the filter at all.

Tim

 

[TDickerson]

The dipstick is difficult to read correctly, read BOTH sides of the dipstick and use the lowest reading. The higher reading is from the dipstick tube touching the stick.





This is so critical. A shop that did my flush did the exact same thing. They only looked at one side of the dipstick and it read full. I drove it home and the transmission was shifting real bad from 1st to second and third. Thought the transmission was going bad. I took it back because my transfer case plug was leaking and asked him to double check the transmission fluid and he showed me it was full. I still had the same problem. Got curious and when I got home I checked the dipstick again and this time I did notice the other side was dry. Anyway, took over 3 qts of fluid to fill it up to the full line and everything was fine.

 

[masterstream]

Problem solved. Thursday morning, I added a quart of ATF and brought the level to the bottom edge of the crook in the dipstick. Have driven 300 miles since and the transmission has shifted flawlessly. Will seriously consider the MagHytec Double Deep pan at my next fluid change. Thanks for all the advice.

 

[LarryWard]

Had the exact problem about a year ago after they serviced transmission and it gradually started acting up. Bad slipping at times but other times ok. Was a real puzzle for weeks. Then had a cooler line leak and lost too much to go at all. Upon refilling it just seemed strange how one side of stick had fluid showing as I kept adding but nothing or very little showing on back side. Finally got it full on front side but not certainly not on the reverse side. So I just kept adding and it took 3 more qts. And it cured every bit of the problems. I only worry about what it may have done to clutches, etc. Fortunately I was pulling no loads during this time. AS they have already said, "read the lowest fluid level" for accuracy. It made me a little nervous to see how high the fluid came up on the front side but that is giving a false reading and it is not overfull. I never went back to that shop to clue them in on their shortfill.