I'm going to be replacing the 5r110W transmission in my 6.0 03 Diesel Excursion. The replacement is a low mileage used unit with a guarantee. I can't afford a full reman right now.

Here's my question: any tips on flushing out the old fluid from both the replacement transmission and from the piping and cooler still remaining in the car? I don't think I can simply blow out the lines in the car because of a thermostat or valve that only opens when the fluid is warm?

Thank you!

Mark

 

The thermostat is in the transmission, not in the lines.

 

Thank you Mark. Given that, any suggestions for getting all the old fluid out of the system and the "new" transmission? I've read so many negatives about transmission flushing fluids and what not.

Can I use "gentle" compressed air on the system left in the car?

How about getting the old fluid out of the new transmission?

 

Do NOT use flushing fluids in the transmission. You can use compressed air to get the fluid out of the coolers. The system runs about 60 PSI, so anything less than that won't hurt anything.

To get fluid out of the trans, I hesitate to even tell you. It might cause major damage. If you want to risk it, it's on you, not me. Take the converter off the trans and dump the fluid out of it. That's the easy part. Getting the converter back in correctly gets screwed up every day. If you don't get it back on correctly you will destroy the converter and the pump. Also drain the fluid in the pan.

 

Thanks so much Mark!

 

Is getting the old fluid out of the cooler and lines with compressed air "good enough". Assuming that the old trans wasn't fragged?

 

If the old trans didn't put too much junk in the coolers that may work. On the other hand, this is a used trans, not a new trans. The best practice is to replace both the aux cooler and the radiator.

 

It's a good question. The old (current) transmission is still working in the car. It has a delayed engagement in reverse and drive and is randomly shuddering or stuttering when pulling away from a stop. I've also noticed the shuddering somewhere around 30-40 when accelerating as well. But it doesn't do it all the time or for long.

It could be the line pressure solenoid but I think there's more going wrong inside, probably clutches here and there.

So I don't think the current transmission has blown up yet or started disintegrating but I do want to get as much of the old fluid and any traces from the old transmission out.