Tranny fluid yellow?

[ericem]

Hey guys, I am thinking the worst, and no I am not looking at my differential dipstick. I thought it would be either red or black, no yellow though... Either way smells like tranny fluid and doesn't smell burnt. I am going to get some tranny fluid and do a oil change I didn't even think to check my diff fluid. It is possible for the diff fluid to mix with transmision right?

 

Car is 94 SS on the 3rd tranny

[porcupine73]

I'm thinking this is an auto trans? Yes it is possible for the front diff gear oil to mix with the ATF if the double lip oil seal between the two on the ATF pump fails.

 

[porcupine73]

Wait but you said you checked the front diff? Gear oils are usually yellow. They're not typically dyed. Some special racing gear oils might be dyed but not your normal run of the mill gear oils for cars.

[ericem]

Hmm, oh and yes it is auto and I am talking about the transmission oil not the front diff going to go outside and check the front diff oil.

[porcupine73]

Usually ATF's are dyed red but I suppose they could be dyed any color really or no color at all. If you checked the ATF, you could also be seeing engine coolant mixed in the ATF if the in-tank radiator ATF cooler has breached. Either gear oil or coolant is very bad for the automatic transmission; generally it trashes the clutch materials.

[ericem]

Rad is pretty new like year old?

[ericem]

I drained the fluid looked fine a bit dark and came out like water if it matters? Put in some new stuff seems like it's better also seems like the awd has less delay if any. Also going into reverse it engages faster etc etc. SO far so good! It is sooo damn difficult to read the dipstick though! I still think it needs more but I don't think I will ever be 100% happy unless I know the dipstick is showing correctly.

 

I am doing it with the car on level ground engine running. Problem is there is parts were it is solid red, and then nothing, thin line, its hard to tell what level it is actually at!

[porcupine73]

Yes reading the ATF is tricky on soobs and I am sure there are threads many pages long on the art of it. I always check it cold, and look for three or so consistent pulls on the dipstick. Then I'm looking for where the fluid is solid on the stick front and back. The rest of the fluid is 'noise'. If you add fluid you have to be really patient, like pull the stick three times or so don't even try to read it just wipe it off, because the fluid will be all over in the tube from having just poured it in there. I know Subaru wants it checked with trans at operating temp but I can never get a reasonable reading that way that's why I do it cold.

 

So what did you see that was yellow in the fluid? If it's watery, it's possible there was condensation in it if it isn't coolant or gear oil.

[Rooster2]

The ATF dip stick is indeed hard to read. The low to high mark is only a pint of fluid, and new ATF is hard to see on the dip stick.

 

Suggest you change your ATF another two times, as you are only changing half the fluid content per each change.

[Fairtax4me]

ATF can be green, red, blue, yellow. Whatever color the manufacturer feels like making it really. It's just typically red. It was that way for easy identification.

Same reason Antifreeze was typically Neon Green, but now there are blue, green, yellow, orange, pink, even some nearly clear antifreeze types.

Power steering fluid is the same story.

Engine oil, ever seen/used Royal purple?

 

Point is, If your car had red ATF, and it mixed with gear oil, don't you think it would still be red? I mean, 2ish quarts of gear oil, vs 9-10 quarts of ATF?

I would be concerned if the gear oil in the differential came out looking the same color as the ATF.

 

I drained the fluid looked fine a bit dark and came out like water if it matters?

Nope, it usually does if it's warm at all. It could also just be a property of the type of fluid. Synthetic fluids generally flow better, which makes them appear to be "thinner" than regular "conventional" fluids.