Does my transmission fluid need to be flushed and replaced

My mechanic has told me that the transmission fluid in my 2005 Chrysler T&C is dirty and needs to be flushed and replaced. The van has 118,000 miles on it. I bought it used with 96,000 miles, and I don’t know if or when the transmission has been serviced. I am having no symptoms of transmission problems. When I check the transmission fluid, the fluid is clear and pink - however, when I wipe the dipstick on the paper towel, there are a few black smudges around the edges of the pink. Does my fluid need to be changed? Should it be flushed, also? If it has never been serviced, am I asking for trouble to flush it with 118,000 mile on it? Thanks in advance for any advice.

There are probably 100 discussions of exactly this question on these boards. About 10 seconds of searching will have you reading all day.

Every 30K miles you should have the transmission pan removed and the filter replaced. You should not have any kind of “flush” or fluid exchange without having the filter changed first. Any shop that wants to do this is looking to rack up $$ from their fancy, overpriced fluid exchange machinery.

Since you don’t know the history of this van you should probably have the pan/filter service done and then a full fluid exchange. If you wait until the fluid looks funny or smells funny or until the transmission feels funny it is already too late. This is like an alcoholic thinking s/he can keep sucking whiskey since s/he doesn’t have cirrhosis yet.

On that van the use of anything other than genuine ATF+4 transmission fluid will cause problems.

Unless the fluid is contaminated, I would just drop the pan, clean it out real good noting any debris in the pan then refill using ONLY ATF+4.


What transman said. Most transmissions will never have a need to be flushed.

I’ll give you reasons that I would consider a full fluid exchange after pan & filter.

  1. Most people do not have their transmissions serviced at all. If this was the case with your van then you have transmission fluid with 118,000 miles on it. After a pan/filter service you will still have about 50-60% of your fluid with 118,000 miles on it.

  2. Another thing that sometimes happens is that people do have their fluid changed by general purpose shops. Many of those will use general purpose transmission fluids that they combine with some “additive” that is supposed to make the fluid into ATF+4 compatible fluid. Its not.

If this was my van purchased at 96,000 miles I would be looking to have a trouble free trip to 200,000 miles. The thing that will most likely interfere with that on these vehicles is transmission trouble. I hate uncertainty about maintenance and would want to wipe the slate clean and start fresh knowing that I had a new filter and a verified 99% genuine, clean, fresh ATF+4 fluid.

After this wiping of the slate, then I would go to pan/filter only every 30K or so.

One source has suggested that if the transmission has never been flushed, flushing it now at high mileage could cause deposits which have been sitting there to become unstuck and circulate into the fluid, thus resulting in problems in the next 1000 miles or so. Any opinions as to the merits of that?

At this age - anything could happen at any time.

The notion that proper servicing of the transmission will actually CAUSE problems is an old wives tale. Many people can have problems after service because a) coincidence; b) the service wasn’t done right (failure to change filter, incorrect fluid); c) they had the service because they started to have problems - in which case it was too late & the service wasn’t the “cause” of the problem.

Servicing a transmission that has lacked for service for many miles has resulted in immediate problems on several occasions for me. Adding one of several transmission “tune up” products always put the vehicle back in service. In recent years I included adding the “tune up” product as part of the service and eliminated the irate customer calls. Trans_X, Trans-Medic, and Sea-Foam all seem about equal. The heavier additives like Lucas never seemed to improve the situation.

Drop the pan and replace the filter, refill with +4 fluid will not hurt the transmission. A flush after doing the above should not hurt anything, but it may not accomplish anything of benefit either. A flush without first dropping the pan and replacing the filter could very well do some damage.

I agree with Keith. IMO I would avoid flushing and just clean filter and replace fluid. As Cig suggests, you will not replace all fluid so another change within 30k miles should be done.