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Changing old transmission fluid

I just returned from a visit to a national trani company. I was basically told it was not worth me changing the fluid. they said that it was like varnish and that changing the fluid was like putting a detergent in the trani and that such would expediate a trani breakdown.

He said within 15,000 miles it will stop working and that I should simply wait and then have it overhauled. The car is a 1999 buick century with 140,000 miles. I had the fluid changed at 80,000 previously,

I cannot afford to get another car nor pay the estimated 2,800 to redo the trani in 6+ months. I use the car for work.

I am actually great about maintaining my car, but I obviously made a mistake. Is there any other alternative.

Thank you


Apparently your transmission people are prophets and could adopt nicknames such as Samuel, Ezekiel or Moses. I can’t even predict what I’ll have for lunch tomorrow. Rather than risk a failure at an inconvenient time, Ezekiel the transmission man wants you to come in soon for a new or rebuilt transmission at great profit (not prophet) to his business.

If your transmission shifts well now and you have driven your car with a measure of caution meaning not trying to kill it, then ask your transmission man what he is basing his diagnosis on to indicate that it will fail within 15,000 miles or does he know that Buick transmissions reliably fail at 155,000 miles?

Did he remove the pan to view the condition and quantity of the expected debris in the bottom of the pan?

You did well by changing your fluid at 80,000 miles. Hopefully you had the transmission filter changed too at that time but that is not fatal.

Change the fluid and filter but have it done elsewhere.

This sounds on the surface like a scam in process.

I’m no expert but this sounds like total hogwash to me. Sounds like this company just wants to rebuild a tranny for you.

They could be right that the transmission is on its way out, but a simple drain and refill will not hurt at all. If anything, it could buy you more time, and either way, its due for a change. Just don’t let anyone do a flush.

I reviewed your post to hear the symptoms of your car’s problems and you did not state any. Apparently your transmission is running fine. If so it is likely to continue to do so for many more years.

Take your car somewhere else. Go to any independent shop and ask for routine transmission service. This requires a pan drop and filter replacement, as also stated above. Do NOT let them talk you into a transmission flush, which is not the same service.

Of course, you may be having valid transmission problems that you failed to mention. It may be possible your transmission is really dying, we can’t tell from your post. If that is indeed the case, then no treatment will do much good… nor will routine service do further harm.

Take it to an independent and have them replace the fluid. No need to ruin a transmission. Whatever happens if it fails soon (may never) don’t blame the shop who replaced your fluid.

While transmission fluid should be changed about every 30k miles I’m skeptical that this fluid has turned to varnish in 60k miles if your original fluid did not turn to varnish in 80k.

If the transmission appears to be shifting fine then simply change the fluid and motor on. If the reason you went to a trans shop in the first place is because of a subtle shifting problem then maybe a fluid change will cure it.
If the shop in question is AAMCO you should take the varnish thing with a grain of salt.

I want to second everything said here and only add that you schedule a transmission oil change every 30k miles from now on. BTW, have you pulled the stick and looked at the fluid for yourself? If its still red, then the transmission shop was feeding you some BS and should be avoided for any reason.

A couple of thoughts:

About 60-70K miles ago I was told by a national chain that my tranny needed a rebuild. I didn’t do it, and 60-70K later still motoring along just fine.

I did have some hard shifting which is why I had it looked at (and I went to the national b/c they do a free diag - but it was obviously a waste of time). I dropped the pan/filter a couple of times in quick succession (w/in 8K rather than 30K). I now just do it about once/yr (equivalent to 20K), and while the tranny still bumps a bit sometimes it has been just fine. I do it myself, so this costs all of about $50 for filter/gasket/fluid, and I get to check out the condition of my pan/magnet on a regular basis.

I don’t know about it specifically, but if the tranny is not operating all that smoothly I have seen the suggestion to use either Berryman’s Chemtool or SeaFoam Transtune - both of which are supposed to be able to clean up varnish in the system if it is there. I would ask around before using it, but I believe that you add it in, drive for 500-1000 miles or so and then change the fluid.

In short - listen to everyone here. If the tranny is functioning well don’t reuild it. Just put it on a more regular service schedule, and maybe schedule 2 services w/in the next 5-10K or so.

You changed transmission fluid more than most owners, and since you took good care of the car otherwise, I would recommend you change the fluid and filter, as recommended by others, but at a good shop. Many GM cars don’t even have a fluid change interval stated.

The sixty thousand miles of gentle driving on the Buick could hardly have worn out your transmission.

The last GM car I sold had over 300,000 miles on the original transmission and it performed flawlessly.

So, spend the $65 or so and happy motoring!

The key to your dilemma is contained in a few words in your original post, namely, “national trani company”. AAMCO, Lee Myles, Cottman, and any other transmission chain that I have ever heard of are all notorious for performing unnecessary “repairs”, overcharging for those repairs, and frequently, for not doing those repairs properly.

Think about it–Why do they want you to defer the transmission fluid change? Most likely, this is because they assume that you will return to them at the first indication that your transmission is not operating correctly, and at that point, they can tell you that the predicted failure of your transmission has come to pass. And, of course, at that point, they will convince you to have them overhaul your transmission–whether it is necessary or not.

As others suggested, go to a trusted independent mechanic for a transmission fluid and filter change. Monitor the level and the color of the transmission fluid periodically, and if you still have the car in 30,000 miles, have the service performed again.

With any luck (and good sense) you will never have to go to a “national tranny” center again. If you do need transmission repair, go to an independent transmission shop that has been in business for at least 3 years. Ask friends, co-workers, neighbors, and relatives for recommendations in the event that you do need transmission repair.

Last year when I had my vehicle surviced ( oil change brakes, etc. ) my normally good mechanic suggested that I have the transmission fluid changed , and the trans flushed since it had 185,000 miles. The transmission had not given me any problems to that point, but I told him to do what he suggested. When I got the van back I noticed that it was shifting from 1ST to 2ND at different speeds and sometimes having a lot of trouble getting out of 1ST. This is a three speed transmission. I took the van to another shop and let a friend drive it, and he told me that I should not have had the trans flushed, and that in that process some dirt got past the filter, and was partially plugging the valve, and the only way they could get to the valve was to take the transmission out, and take it apart which would cost about $1000.00. He said that since he had it out he would rebuild it, and only charge me for the parts which he did. If IT Ain’t Broke, Don’t Fix It !

As an added note, don’t have the transmission FLUSHED, whatever you do. This action can really mess up an old transmission. Just drain the fluid and change the filter. If the shop suggests otherwise, just leave!

Thanks for the help. The car has always run great. I plan to take the advise of everyone and get it manually changed by my local mechenic and do this every 30K going forward.

I mentioned my problem the other day to a friend and he said that when he had gone to AAMCO (same shop) to look at his son’s car, they said the problem was the trani and would fix for 2,800. The car cost about 1,000. They were wrong, all that was wrong was that the spark plug wires were worn out. Hoe do these people/thieves get away with these things/

Thanks again

Don’t blame them for such behavior. It’s in their name:
All Automatics Must Come Out!

You might reset the engine computer by disconnecting the ground from the battery for about a half hour. Ask the shop to do it while the work is being done. I have been told that some cars will adapt to the amount of clutch slipping and changing the characteristics of the fluid suddenly (i.e. new from very spent) can cause slipping.

My GM dealer in Tucson did not flush transmissions. A flush machine was not a required dealer piece of equipment. Now after a transmission overhaul the lines and cooler were flushed this is critical