Dirty Tranny fluid ...flush or drop pan????

[jimbo231]

My 01 sport which has 140000 km on it has dirty tranny fluid. I think it was probably the original. I want to get it changed but a few people I talked to said the flush which changes all the fluid could possibly cause problems. What do you recommend?

 

[BrooklynBay]

Remove the pan, replace the filter, and refill with the correct fluid. Check the sides of the valve body gasket for deterioration, and the valve body bolts to see if they are loose. Pay extra attention to the EPC solenoid area.

 

[deweyville65]

Remove the pan, replace the filter, and refill with the correct fluid. Check the sides of the valve body gasket for deterioration, and the valve body bolts to see if they are loose. Pay extra attention to the EPC solenoid area.

+1 above Changing the fluid by flushing seems to be a recipe for disaster with Explorers, at least the older ones.

 

[jimbo231]

So dropping the pan won't cause any problems? What if I just got all the fluid exchanged without flushing. Is the 100% new fluid what causes the problems or the flushing chemicals that do. I just want the fluid to be really clean since its so dirty now won't just dropping the pan still leave it really dirty?

 

[BrooklynBay]

The power flushing machines back wash the system which causes dirt to come off the filter & go into the transmission. Adding a quart while draining a quart will replace all of the dirty fluid in the system but leave the filter dirty. New fluid has strong detergents so some people are afraid to use it in an old transmission. Driving it with dirty fluid, and a filter won't help it either.

 

[koda2000]

the "dirt" in you fluid (unless it's burnt) is clutch material. changing 100% of the fluid will flush out suspended clutch material, the new clean fluid will likely cause your transmission to begin slipping because your clutch packs are worn out. within a couple of weeks it may lead to transmission failure. if you change only the fluid in the pan (and the filter) you'll be leaving behind some of the suspended clutch material, which will allow the transmission to continue to function with some fresh fluid. the choice is yours.

 

[jimbo231]

The power flushing machines back wash the system which causes dirt to come off the filter & go into the transmission. Adding a quart while draining a quart will replace all of the dirty fluid in the system but leave the filter dirty. New fluid has strong detergents so some people are afraid to use it in an old transmission. Driving it with dirty fluid, and a filter won't help it either.

So your saying the best option still is to drop the pan and do the filter?

 

[BrooklynBay]

Yes.