Transmission Fluid Brown After 3,000 Miles.

[HylianOverlord]

I recently installed a used transmission in my 1994 Frord Explorer XLT and after 3,000 miles I checked the fluid and it was brown. I was wondering what could cause this to happen. Any help would be appreciated, thank you. If you need any more information feel free to ask.

 

[Rhett]

Dirty, old fluid ,and/or fluid that has been run really hot. Was this trans recently rebuilt?

Either way I would not run it like that, I would get all of the the fluid out and change the pan filter. The best procedure is in one of the stickied threads I believe.

 

[natenkiki2004]

Sounds like rust to me. Might have gotten water in it if it was a used pull. Definitely get the fluid out and toss an external filter on that bad boy.

 

[HylianOverlord]

Dirty, old fluid ,and/or fluid that has been run really hot. Was this trans recently rebuilt?

Either way I would not run it like that, I would get all of the the fluid out and change the pan filter. The best procedure is in one of the stickied threads I believe.

I don't know the history of the transmission, all I know is that the vehicle it came off of had roughly 100,000 miles on it.

 

[Rhett]

I don't know the history of the transmission, all I know is that the vehicle it came off of had roughly 100,000 miles on it.

Probably sat for a long time and/or was never changed. I'd do a fluid change, then wait two weeks and do a second one.
You'd think whoever put in the trans put in new fluid but I have seen stranger things.

By fluid change I mean pan drop/filter change too. The truck's pump-out rate is about 7 seconds to 1 quart. No need for one of those flush machines.

 

[HylianOverlord]

Probably sat for a long time and/or was never changed. I'd do a fluid change, then wait two weeks and do a second one.
You'd think whoever put in the trans put in new fluid but I have seen stranger things.

By fluid change I mean pan drop/filter change too. The truck's pump-out rate is about 7 seconds to 1 quart. No need for one of those flush machines.

My uncle was the one who installed the used transmission and he changed the fluid, but he did not do a flush.

 

[2stroke]

Its nothing to be overly concerned about if it shifts fine, just flush the fluid out through a cooling line until it comes out red. After that, just change the fluid by dropping the pan and changing the filter ever 30,000 miles. That transmission probably has the original fluid.

 

[HylianOverlord]

Its nothing to be overly concerned about if it shifts fine, just flush the fluid out through a cooling line until it comes out red. After that, just change the fluid by dropping the pan and changing the filter ever 30,000 miles. That transmission probably has the original fluid.

No, the fluid was changed when my uncle installed it.

 

[HylianOverlord]

Sounds like rust to me. Might have gotten water in it if it was a used pull. Definitely get the fluid out and toss an external filter on that bad boy.

To add credit to your theory, I did find rust on the top of the transmission fluid dipstick. Also, what good would an external filter do?

 

[natenkiki2004]

To add credit to your theory, I did find rust on the top of the transmission fluid dipstick. Also, what good would an external filter do?

It's likely just enough surface rust on some interior parts to discolor the fluid but not enough to cause problems. An external filter would actually filter the transmission fluid. The internal filter is about as fine as window screen, it is basically there to keep big chunks out but not filter the fluid. It's akin to the oil pickup in the engine, it's got a screen on it but that's not what filters the oil. Installing an external filter will catch all the particulate. Still a good idea to change the fluid though. See my signature on how I cleaned up my fluid.

 

[HylianOverlord]

It's likely just enough surface rust on some interior parts to discolor the fluid but not enough to cause problems. An external filter would actually filter the transmission fluid. The internal filter is about as fine as window screen, it is basically there to keep big chunks out but not filter the fluid. It's akin to the oil pickup in the engine, it's got a screen on it but that's not what filters the oil. Installing an external filter will catch all the particulate. Still a good idea to change the fluid though. See my signature on how I cleaned up my fluid.

Which one in the signature am I to refer to?

 

[trashtruck]

mods; filter; trans spin-on

 

[2stroke]

Your uncle may have dumped the fluid in the pan, but that only accounts for about 1/3rd of the total fluid. You also have fluid in the transmission body and in the torque converter. An external filter is a great idea, but you can't filter bad oil.

 

[HylianOverlord]

To add credit to your theory, I did find rust on the top of the transmission fluid dipstick. Also, what good would an external filter do?

I've been doing some more research and I'm not sure it can be water because the fluid isn't pink and milky.

 

[natenkiki2004]

I've been doing some more research and I'm not sure it can be water because the fluid isn't pink and milky.

You're right, it wouldn't be a lot of water. I'm thinking more along the lines of condensation and surface rust as opposed to a 60 year old tractor sat out in the field with a crankcase full of water. Either way, the fluid should be changed and a filter added. If it is surface rust, it will likely contaminate the fresh fluid so a filter will help.

 

[HylianOverlord]

Bad news guys, it did it again, the fluid went brown. This time I took it to a trans shop and good it looked at, the auto tech says the fluid smells like burnt clutch material. He says this is also causing it to overheat and burn the fluid. The inline filter did stop the clutch material though because I can't see any in the fluid. Could it be as simple as replacing the solenoid or do I need to replace the torque converter too?

 

[natenkiki2004]

How brown is it? Have you looked at it on a paper towel? Is it as brown as it was before? It may be residual fluid from before that's coloring it. I'd do another flush and see what happens. If it comes back in 3 months exactly as it did before when this all started, start putting money away for a trans overhaul and run it until it pukes.

 

[HylianOverlord]

How brown is it? Have you looked at it on a paper towel? Is it as brown as it was before? It may be residual fluid from before that's coloring it. I'd do another flush and see what happens. If it comes back in 3 months exactly as it did before when this all started, start putting money away for a trans overhaul and run it until it pukes.

How hard is it to change a solenoid? Can I do it while I am changing the fluid?

 

[HylianOverlord]

How hard is it to change a solenoid? Can I do it while I am changing the fluid?

How brown is it? Have you looked at it on a paper towel? Is it as brown as it was before? It may be residual fluid from before that's coloring it. I'd do another flush and see what happens. If it comes back in 3 months exactly as it did before when this all started, start putting money away for a trans overhaul and run it until it pukes.

It's not as brown as before, but is only one or two shades lighter that it was before. I know it isn't locking up though because it goes into fourth, but the tach reads about 2700 rpms, when it should read around 2000 rpms.

 

[natenkiki2004]

Don't put too much faith in the factory tach, it may be off quite a bit. As far as I know, the solenoids come out from the side of the trans and might be a pain in the ass. You might have to remove the valve body to do it as well.