Transmission slips; ATF slightly brown

[Alex89gp]

Hello,

My car sat without being driven for about a year, but I would start it up once every few weeks to keep the engine seals from drying out. Recently, I got the car on the road, but the transmission seems to be slipping a little in all gears. The fluid was about a litre low due to some gasket seepage. I noticed the ATF had also turned slightly brown, but does not smell burnt. The colour wasn't noticeable by looking at the dipstick, and I only discovered it when I put a few drops on a white rag. I plan on doing a full fluid change soon, but is it possible that my transmission is damaged? Can ATF start turning brown from sitting? Is ATF less effective after sitting?

TIA,
Alex

 

[chad8]

It either oxidized or got some condensation in it. Not the best situation . Change it soon. rust never sleeps. yes it can damage the transmission and probably already has.

 

[eljefino]

What car and transmission?

If its a 1989 Pontiac Grand Prix with the 4t60, try yanking the vacuum line to the modulator. Should not slip and firm up.

 

[ethangsmith]

What kind of car is this? And also if you know what kind of fluid is in it (Dexron, Mercon, ATF+4, J2, ATF-HP, etc.) post that up too. Generally when a transmission is slipping, damage has been done. However, in your case, it could be an issue of sludge or varnish building up in the valve body that needs to work its way out- however this most likely is not the case. Some fluids turn slightly brownish with age. Mercon V seems to really brown up after a few years of use. The fluid may have absorbed moisture while sitting and the small amount of driving could have caused it to oxidize and age a bit. Since changing the fluid on a transmission is inexpensive, I would start with that and see what happens. Usually once a transmission is slipping, damage has been done though.