: How often do you service your transmission?

01-21-10, 07:27 PM
How often so you service your automatic transmission? I am thinking of doing mine for the first time at 85K miles.

01-21-10, 07:57 PM
What are you getting done?

01-21-10, 08:15 PM
I bought my 79 in 2005 with 61k miles. I don't know what happened service-wise before I had it. I changed it again last May with about 85k miles.

01-21-10, 08:35 PM
Always upon arrival of a preowned one. All fluids, filters, belts and hoses just to get a fresh start so I have no surprises on the raod.

01-21-10, 09:15 PM
Dave, what did you have done to it and what were the results?

01-21-10, 09:15 PM
Every 50 k I get all the ATF out by disconnecting transmission line at the radiator and running the engine in Park for a minute or so. Sure, I replace the filter, clean the pan as well.

01-21-10, 10:51 PM
I was sitting in a class at a GM Training Center during the mid-80's and we had a Cadillac engineer tell us that, in his opinion, an automatic transmission should never be serviced although it was recommended in the owners manual. I dont know that I agree with that but, I thought it was interesting. I'll be honest, I have never serviced a transmission in any car that I have ever owned and have never had a transmission issue with the exception of a failed govenor in a mid-90's Chevy pickup BUT, I think it depends on how the vehicle is driven and under what conditions. I have put over 200K on Chevy trucks without servicing the trannys with no issues at all. My car, a hearse, is used 95% of the time in town and, most of the time, it never reaches full operating temperature so, under those conditions, I would say it should be serviced more often than normal. The car weighs nearly 6000 pounds so, there is a lot of strain on everything trying to move it. At 85K, mine was never serviced by the previous owner unfortunetly so, I hope changing the fluid and filter does not cause any problems at this point.

durrk johnson
01-21-10, 10:56 PM
I was thinking of getting mine serviced because it seems like its shifting a little hard from 1st to second... Like when gears switch you feel the car switch gears. is that normal?

I didnt think it would be like that because thats how it was with my 80CDV.

But i just got the fluids checked when i got my engine serviced and they said all fluids were fine... That is, if they really checked them....

01-21-10, 11:08 PM
What color is the fluid?


If your fluid is in the middle color, and your transmission is giving you no problems, then I would recommend just doing a pan drop and filter change. If you've noticed the transmission being hesitant, making abnormal noises, or giving off general singes of a possible issue, I recommend a power flush through the filter, which you then have to change.

If the fluid is closer to the one on the left, then I would recommend you not servicing the transmission at all. The dark brown is an indicator of friction material in the fluid, and changing/flushing it out will cause the transmission to begin slipping and die prematurely. With that fluid color the transmission can be considered dead and failure imminent.

01-22-10, 02:59 PM
My manual calls for a fluid/filter change every 100k miles. I forgot and let it go until 106933 miles. The difference after service was very clear - it shifted like a brand new car all over again! Shifts between gears were smooth and didn't exhibit slippage like old cars often do.

01-22-10, 03:55 PM
I change my ATF fluid on everything I own once a year. My buddy who owns a tranny shop says for 90% of People they can forget about mileage, just change it once a year and they will never see him. Also if your tranny fluid changes color you already caused damage to your tranny, it should look as good coming out as it does going in. It is cheap Insurance IMO.


01-22-10, 05:39 PM
^Transmission fluid will darken after a week of use.

01-23-10, 04:40 PM
I am very leary of servicing my transmissions. I've owned cars and never done it. But I had it done on my 91 Brougham (first time) and blew the tranny within a month, and I dont drive her hard at all.
My friend had his tranny serviced on his 96 Roadmaster wagon by a different shop, and then blew his two weeks later.
Soo I am very leary of touching the tranny. I've talked to mechanics who say not to do it because it will ruin the transmission. Idk?

01-23-10, 07:20 PM
In my experience I have found that if you change the tranny fluid regularly from when the car was new it will be fine. If you have a car with 100k+ miles and it has never had a service just let it be. Its too easy to dislodge a piece of gunk in there and screw the whole thing over. On the farm truck we change the fluid (NEVER flush it) about every 25k miles because it does a lot of heavy hauling. All our other cars we just let it be.

01-23-10, 07:36 PM
^Transmission fluid will darken after a week of use.

I guess, but not that noticable, All of my vehicles if I pull the dipstick right now will look pink and clean, if they start to look crimson you are damaging your tranny. I know people who think the color is how you tell when to change it and all I am saying is that is a bad idea. it should look like good fluid on the way out.