1999 explorer transmission

1999 explorer…130K miles… transmission fluid brown, and trans beginning to slip (very occasional)…

Should I flush the trans and replace filter?

My mechanic recommends leave it alone… says new fluid will make it worse?



A fluid change will not make it worse, but on the other hand, it is unlikely to save it if it has not been serviced every 30k. But, before I invested in a rebuilt transmission, I would at least drop the transmission pan, clean out the debris, change the filter, and refill it with the correct specification trans fluid.

Agreed with VDCdriver.
Brown and slipping is not a good sign.

Ya know what I’d do?

Drop the pan and see if there’s any debris that indicates the tranny’s on the way out. If none is found except for the normal clutch material, put in a new filter and refill the tranny. If after driving it a period of time and the slipping stops, have the rest of the tranny fluid exchanged.


In 1999 some Ford torque converters still had drain plugs. If you have a 4R70W, you probably do. Take off the transmission pan and have someone experienced in transmissions look in there. If it looks salvageable to them, Drain the TC, install a new filter and reset the PCM (computer) by unhooking the battery while you are doing all this. Lastly, pray. You need the help. You will need about 15 quarts of Mercon V.

Brown fluid and slipping trans = damaged friction material. Overhaul time.