4x4Wire TrailTalk

97 4-rnr tranny-coolant mix

Posted By: skered53

97 4-rnr tranny-coolant mix - 07/31/08 06:17 AM

178 k miles, on Monday I experienced a high temp issue, seems the rad core/heat exchanger cracked causing a mixture of tranny fluid in the coolant & worse, coolant in the tranny fluid.
Replaced radiator, flushed coolant system.
Drained tranny, dropped pan and replaced screen and gasket, drained two lines going to radiator. added 4 and 3/4 quarts to tranny, will test it tomorrow. idled it for 15 minutes to check for leaks and to double check fluid level, didn't test drive as I was ahh a little dirty ;-)
I plan to replace tranny fluid at 28 miles, 56 and 100 miles or until there is now trace of water. ( it's 14 miles to work )
I was quoted $ 2K to rebuild the tranny at the sight of the fluid. Needless to say I got a 2nd opinion.( and did the above myself).
IS there anything else I should do ?
Also, what brand and type tranny fluid should I use once I'm done with the flushing cycles?. There;s the cheap stuff in there for now.

Thanks for any help.
Posted By: Adam F

Re: 97 4-rnr tranny-coolant mix - 07/31/08 09:46 AM

Do a search for "milkshake" or "flush" This problem has been answered a few times here recently. I went into detail about how to flush it.

Just draining what you did probably will not be enough.


Here...I did the search for you


http://www.4x4wire.com/forums/showf...13&Number=1092804&Forum=,f13
Posted By: skered53

Re: 97 4-rnr tranny-coolant mix - 07/31/08 01:56 PM

Thanks for the link/search.
Do you know which of the cooler lines in the pressuer and which is the return ? If not I can just pull them and run her for several seconds till one of them shoots some out.
I'll add a section of hose to the return line, run it vertical and add fluid through a large funnel. That should take care of the flush.
Should I by-pass the raditor heat exchanger and install a seperate x-mission cooler ? I'd hate to go through this again.... any suggestions ? do they make one that has it's own thermostat ?
Thanks, Derek
Posted By: yotaman1224

Re: 97 4-rnr tranny-coolant mix - 07/31/08 03:07 PM

you could prolly take it to a tranny shop and they would prolly flush it for not too much money, ive heard of people actaully using water in there tranny to git home lol, of coarse the tranny didnt last long
Posted By: Adam F

Re: 97 4-rnr tranny-coolant mix - 07/31/08 10:16 PM

Not sure which line is which. Just do like you said and it should be ok.

Its a good idea to get a separate cooler. They are cheap.

No need for a thermostat, the fluid just runs continually through the cooler and through the transmission.
Posted By: Jeff the marmot

Re: 97 4-rnr tranny-coolant mix - 08/01/08 12:33 AM

Jiffy Lube/Grease Monkey type of places do a transmission flush for around $70. They are doing the same thing as what you'd do to disconnect the transmission cooler lines at the radiator for the full flush.
Posted By: skered53

Re: 97 4-rnr tranny-coolant mix - 08/01/08 06:10 AM

I drained the 4 quarts this evening and it looks a little better, but I'm not sure of the system capacity ?.
I'll buy 3 or 4 cases tomorrow and plug my new funnel into the return ( from the cooler) line and just keep adding fluid til it comes out clear from the cooler... I;ll drain the 4 quarts fron the pan first. Will idling simulate/cause the fluid to cycle thru the entire tranny or should I put it on jack stands and put it in drive while I'm doing this ?

If I do install a seperate tranny cooler,,,, I should by-pass the radiator so as not to repeat this should the radiator start to fail again, right ??? Has anyone done this ? do I just mount one in front of the air conditioning radiator thing ?
and if I do by-pass the section of the radiator, do I just plug the nipples or do I need to rig up some way of having anti freeze in there ??
Posted By: Adam F

Re: 97 4-rnr tranny-coolant mix - 08/01/08 03:15 PM

Capacity is somewhere around 12 quarts I think. You'll need to run as many quarts as it takes through the system until it runs clean.

Yes, just mount the new cooler in front of the condensor.

Yes, just plug the nipples. Some vacuum caps will do. Leave it empty.
Posted By: skered53

Re: 97 4-rnr tranny-coolant mix - 08/02/08 07:10 AM

bought 9 gallons today,
the longer line is the return line. the fluid will sprut out the fitting with the elbow so i added a 3 foot section of clear tubing coiled it into a drain pan, then rotated the long hose vertical and stuck the funnel in it, slowly poured the fluid in, it took 5 gallons ( including draining the pan ) to get it to come out good n red. took me about an hour of pouring with the engine idling..... did i say i was pouring real slowly ?.

I'll drain the pan after a week and take a look

Planning on installing a external cooler in a week or so, most likely get one from auto-zone as their website shows several that will fit my rig. I post about it.
Thanks for all your help.
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