Radiator and Trans Flush check list...

[jonathon]

Finally got all the parts together to replace my rad, flush my trans(filter of course), and install my cooler.. never done this before, but I think it should be fairly easy.

I think I've got an idea of how the trans flush should go, but would someone care to post the DIY procedure? I've read different ways to do it and I want to do it safely. I've got 18 quarts of MD-3, think it'll be enough?

How much coolant should I plan on replacing? All that's in there now was replaced just before I got the truck, so I shouldn't have to flush it. I've got 5 unmixed gallons of anti-freeze on hand..

And any tips on keeping the anti-freeze mostly contained? Some spillage would be okay, but I'd like to avoid turning the barn into a superfund site

Thanks guys

 

[troutbum_mt]

I am by no means an expert at this and had to do some research when I flushed the trans on my K5. The process I read basically said to drain the trans, fill it and run it through the gears and then drain it again and repeat. The reason being that you are trying to remove the old fluid from the system and it dumps back into the new stuff as it flows through. You basically want to get all the old fluid out through the tranny and torque converter. I think I went through like 2 and a half gallons (including the final fill) when I did it this way IIRC. I am still going to take it in and have it done professionally because it seems like doing things this way you never get out all of the old fluid out and mine was very old and pretty trashed.

As far as the radiator goes, is there a petcock valve at the bottom? Mine is at the bottom corner on the driver's side if that helps. That and a drain pan would help keep things somewhat contained.

Hope this helps. Like I said, I am by no means an expert and somebody here might have a better way. It was my first time doing it too :-) Best of luck.

 

[jonathon]

I'm thinking of changing the filter, and then dumping the cooler lines into a bucket to drain them.

Suggestions I've read said fill a bucket with clean atf and put the lines in there and run the truck at idle, to just dumping the out cooler line in the bucket and continually pooring fresh trans fluid down the dipstick.

 

[troutbum_mt]

I'm thinking of changing the filter, and then dumping the cooler lines into a bucket to drain them.

Suggestions I've read said fill a bucket with clean atf and put the lines in there and run the truck at idle, to just dumping the out cooler line in the bucket and continually pooring fresh trans fluid down the dipstick.

Personally, I would go with the dumping the cooler line in the bucket and adding new stuff method if it were me. At least that is what I did when I went through the process a month ago. That way you insure you are getting most of the old stuff out. From what I read, the problem is that a lot of the fluid recirculates so you will never get all the old stuff out unless you use tons and tons of tranny fluid.

I wish some of the pros here would chime in because I would be curious to learn the best way myself and when is the best time to put in the new filter. I mean it seems that if you replace the filter right off the bat and then go through the process you are just trashing a new filter with the junk that is already in the system. But like I said before, I am a newb at it too. Hopefully by adding more posts to your thread it will attract some attention from the really knowledgeable people here.

 

[muddermilitia]

hope you dont mind a slight hijack, what would be the best way to flush out the trans cooler thats in the radiator? Lines are not hooked up to new tranny yet.

 

[jonathon]

Don't mind at all

 

[troutbum_mt]

hope you dont mind a slight hijack, what would be the best way to flush out the trans cooler thats in the radiator? Lines are not hooked up to new tranny yet.

Doesn't mean it is right, but I blew them out with an air compressor. Put the nozzle on the in line and blew for all it was worth hoping to push all the crap out the other line. That's what I was told to do but like I said, it doesn't mean it is the right way.

The bucket method would work too I think. You put new fluid in through the dipstick and let it cycle out through the transcooler return line and into a bucket or drain pan. But it does waste a lot of fluid. I guess that's why I was told to drain it and blow it out but I don't know. The key I was told was to wait until the fluid draining out is new fluid and not the old stuff (color and smell change for an indicator).

Here's exactly what I did. I drained the fluid from the pan, blew out the cooler, put the pan back on, added new fluid and cycled the old fluid out by adding new fluid through the dipstick and let it fall into a drain pan. Mine was really old fluid so the color change was pretty apparent. I didn't keep the pan full because I knew I had to drop the pan and replace the filter once that was done. Once I was getting new fluid out the transcooler, I dropped the pan, replaced the filter, replaced the gasket, sealed it up, reconnected the cooler return line. Then I added more fluid and ran it through the gears (supposedly this helps cycle the new fluid through so important to do while getting rid of old fluid too) and kept checking the fluid level and adding more as needed until it was full.

I really wish some of the very experienced people would answer because it seems it would help a lot of people. Up to 3 and counting

 

[BGKYK5]

Subscribed, I need to do this too. I just changed the trans fluid and it still looks bad because it has mixed with all the old stuff that stayed in the converter.

 

[dyeager535]

There is an older thread on this topic.

If you are going to do it this way, you need to let the trans pump out a couple of quarts in park, turn engine off, fill, and repeat.

Trans fluid return needs to be under pressure to refill so you can't just dunk it in a bucket.

Personally I believe a flush machine is the correct way to do a flush, but I was pretty much in the minority the last time.

 

[muddermilitia]

Doesn't mean it is right, but I blew them out with an air compressor. Put the nozzle on the in line and blew for all it was worth hoping to push all the crap out the other line. That's what I was told to do but like I said, it doesn't mean it is the right way.

The bucket method would work too I think. You put new fluid in through the dipstick and let it cycle out through the transcooler return line and into a bucket or drain pan. But it does waste a lot of fluid. I guess that's why I was told to drain it and blow it out but I don't know. The key I was told was to wait until the fluid draining out is new fluid and not the old stuff (color and smell change for an indicator).

Here's exactly what I did. I drained the fluid from the pan, blew out the cooler, put the pan back on, added new fluid and cycled the old fluid out by adding new fluid through the dipstick and let it fall into a drain pan. Mine was really old fluid so the color change was pretty apparent. I didn't keep the pan full because I knew I had to drop the pan and replace the filter once that was done. Once I was getting new fluid out the transcooler, I dropped the pan, replaced the filter, replaced the gasket, sealed it up, reconnected the cooler return line. Then I added more fluid and ran it through the gears (supposedly this helps cycle the new fluid through so important to do while getting rid of old fluid too) and kept checking the fluid level and adding more as needed until it was full.

I really wish some of the very experienced people would answer because it seems it would help a lot of people. Up to 3 and counting

I see what you mean, I was thinking of using compressed air as well, but maybe turn down the regulator a bit. The bucket method wont work for me as I don't want to put any of that old oil through the brand new $$$ transmission.