Transmission cooler circuit flush (1 Viewer)

[Malleus]

EDIT: The very first page of the repair manual says to use ATF or kerosene for cleaning (just goes to show you should read the manual). So alcohol is probably not on the list...

I'm cross posting this from the 100 series forum, because the two systems are similar enough to be the same (at least for my purposes).

I'm overhauling a 2000 LX450 A343F. Since the transmission has only one forward gear, and had been steadily degrading from slipping in all forward gears to non functional when parked, I'm hoping all I see is bare clutch disks and worn steels. I know I'm going to see at least that.

Anyway, I don't want to put a clean, working transmission and torque converter back in the truck, knowing the system is contaminated, so I'm planning to flush the cooler lines from/to the transmission, before I reinstall it.

I'm interested to hear what and how others have done this, before I go reinventing the wheel. I was planning to use a drill driven pump at one open end of the circuit, flushing the circuit with cleaner/solvent and then ATF to run that out. I don't want to use ATF to clean the system; it's too expensive. I haven't decided what to use yet, but I'm leaning towards alcohol.

If anyone has experience with a better plan, I'd like to hear from you.

 

[Kernal]

This is what some rebuilders recommend before installing a new/rebuilt automatic transmission.

KOOLER KLEEN Transmission Cooler & Line Flush with NEW 2-in-1 Fitting - Lubegard

www.lubegard.com

On a FZJ80 with the A343F transmission:

I used an aerosol can of the Kooler Kleen, blew it into the cooler hose that goes to the right lower side of the radiator while the return hose coming from the factory Aux cooler was disconnected. I didn't collect the cleaner that came out the other side but it might have been interesting to see what came out.

I then reconnected the OUT cooler hose leaving the return cooler hose (coming back from the Aux cooler) disconnected and started the engine to allow the transmission pump to pump some ATF through the transmission cooling circuit. I did this as I don't have compressed air but the purpose was to remove any remaining cleaner along with any loosened particles, then I reconnected the return hose and topped off the transmission.

Tip: the hose tip that comes with the Kooler Kleen can is theaded, our
lines are not, so IIRC I just stuffed the plastic hose into the rubber cooler line and held it tightly or put a small clamp on it before blowing it into the lines.

KOOLER KLEEN Transmission Cooler & Line Flush with NEW 2-in-1 Fitting - Lubegard

www.lubegard.com

 

[Malleus]

I'll check that out. Thanks! Since this is an LX470, the cooler system isn't as easy to get at as the 80's is. I really only have access to the transmission in/out ends of the cooler lines (this system design was NOT intended to make any mechanics happy). If I could (without too much difficulty) remove the cooler system, I'd just clean each part, but that thing is more work to get out than the transmission was (and that wasn't a cakewalk).

 

[Malleus]

This is what some rebuilders recommend before installing a new/rebuilt automatic transmission.

KOOLER KLEEN Transmission Cooler & Line Flush with NEW 2-in-1 Fitting - Lubegard

www.lubegard.com

I used an aerosol can of the Kooler Kleen, blew it into the cooler hose that goes to the right lower side of the radiator while the return hose coming from the factory Aux cooler was disconnected. I didn't collect the cleaner that came out the other side but it might have been interesting to see what came out (if collected in a clear containter).

I then reconnected the OUT cooler hose leaving the return cooler hose disconnected and started the engine to allow the transmission pump to pump some ATF through the transmission cooling circuit. I did this as I don't have compressed air but the purpose was to remove any remaining cleaner along with any loosened particles, then I reconnected the return hose and topped off the transmission.

KOOLER KLEEN Transmission Cooler & Line Flush with NEW 2-in-1 Fitting - Lubegard

www.lubegard.com

That looks interesting; I'm curious how much volume a 13.5oz can will take up in that circuit. If I could (easily) get at the cooler inlet/outlet that would obviously be enough.

 

[cruiserdan]

Can you get to the external cooler?

 

[Malleus]

Can you get to the external cooler?

Well, yes but..the 100 series front end is a nightmare to tear into. Which is just one reason why I sold mine and replaced it with my 80

This is my son's LX. FWIW, I'm doing this work for him, since he's in school, miles away (driving my other 80), which is why I'm not really hot on tearing the front end apart to get at the cooler (I already pulled the transmission for him). If he was doing this, I'd have him tearing the entire system apart

 

[Malleus]

This is what some rebuilders recommend before installing a new/rebuilt automatic transmission.

KOOLER KLEEN Transmission Cooler & Line Flush with NEW 2-in-1 Fitting - Lubegard

www.lubegard.com

I used an aerosol can of the Kooler Kleen, blew it into the cooler hose that goes to the right lower side of the radiator while the return hose coming from the factory Aux cooler was disconnected. I didn't collect the cleaner that came out the other side but it might have been interesting to see what came out (if collected in a clear containter).

I then reconnected the OUT cooler hose leaving the return cooler hose disconnected and started the engine to allow the transmission pump to pump some ATF through the transmission cooling circuit. I did this as I don't have compressed air but the purpose was to remove any remaining cleaner along with any loosened particles, then I reconnected the return hose and topped off the transmission.

KOOLER KLEEN Transmission Cooler & Line Flush with NEW 2-in-1 Fitting - Lubegard

www.lubegard.com

Now this is more like it:

I'm sure a barrel will do the job! Napa seems to have the market corned on everything Lube Gard makes. How have I not heard of these guys before now?

 

[Kernal]

I've used the LubeGard Transmission flush product on two different 80's over the years (a bottle or two, not a barrel). No issues.

 

[jaymar]

Also look up ‘Rodney flush” if you’ve not come across it, though I believe he uses atf…