Well I can tell you this,I have had my XJ for 11 years and shortly after i got it the radiator collapsed internally,allowing the coolant and trans fluid to mix,what a mess,pulled the trans dip stick and it started overflowing with strawberry milkshake mess,when it happened I knew exactly what it was and NEVER have seen that happen on any vehicle i have ever owned,first thing i did was grab a drain-pan,crawled under the jeep and pulled the plug for the tranny,thank you Jeep,
pulled every coolant hose and washed them all out,flushed engine and radiator out with water until clear
put plugs in radiator for the tranny lines,filled with new coolant,new tranny filter and fluid,bypassed the radiator with tranny cooler in front of the radiator. went for a drive,or tried going for a drive,no forward gears,only reverse.next day drained tranny and checked filter again,flushed tranny with new fluid down dipstick tube with funnel,and had tranny line in bucket,adding new while watching crap fill bucket.this was with jeep running to pump out old mixed tranny fluid,coolant mess.
got everything back together and this time I had forward gears(all) but no REVERSE. drove it like this for awhile.until I aquired a used AW4 from a wrecked XJ for 75.00.been running it with the swapped AW4 and tranny cooler and same radiator for the last 10 years,although I could definately use a new radiator now.when I get a new one,the tranny cooler will NOT be getting hooked into the new radiator. Just something to think about,never thought a radiator could collapse internally,since they are two different tanks,but it happened to me.I live in tennessee so it don't get that cold down here,coldest I seen it was 0 degrees. no problems and I tow with my jeep.
sorry for reviving an old thread but just may save some jeeper's from doing a tranny,radiator, and one big mess from happening in the first place.
Before moving to Tn. in 2006 I lived in Pa. for 42 years,all my cars that had tranny coolers,were bypassed from the radiator without any problems in Pa. cold winters, and as you can tell i keep my cars running for 10+ years.with regular maintenance. and also work on cars for friends and family,it is my 2nd job.
Last edited by jeff540; 10-18-2013 at 08:11 PM.