macattack Posted February 19, 2014 Share Posted February 19, 2014 hey gang.seems like i got some tran fluid sitting in my coolant resovoir. thinking the tran cooler has a leak.anyways the rad in my mr688s has the tran cooler at the bottom of the rad inside the bottom tank. the bottom tank is bolted to the rad bottom with a bunch of bolts, has anyone removed all the bolts at the bottom to replace or service the cooler itself.thinking maybe i could just service the cooler without removing the rad.thanks Quote Link to comment https://www.bigmacktrucks.com/topic/34753-tranny-cooler-questionauto-trans/ Share on other sites More sharing options...
fullfuel01 Posted February 20, 2014 Share Posted February 20, 2014 Oups, you will need a tranny rebuilt. When antifreze get in the tranny, it ruin the clutch pack. Sorry for the bad news.. Quote Link to comment https://www.bigmacktrucks.com/topic/34753-tranny-cooler-questionauto-trans/#findComment-233580 Share on other sites More sharing options...
gearhead204 Posted February 20, 2014 Share Posted February 20, 2014 macattack: loosen the drain plug on trans after it has sat for a while (overnight) and see if any coolant is in oil pan of trans. since the trans oil is at a higher pressure than the coolant you might get lucky. on the cooler you could add a aux. fined cooler and by pass internal rad.cooler. If you don't have a crossmomber in the way you could remove bottom tank but if the side support bracket bolts break off you will be on your back drilling them out or pulling the rad......food for thought. Quote Link to comment https://www.bigmacktrucks.com/topic/34753-tranny-cooler-questionauto-trans/#findComment-233582 Share on other sites More sharing options...
macattack Posted February 20, 2014 Author Share Posted February 20, 2014 i dont think i have any coolant in the trans. fluid there did not seem to rise, but will check again. are the side support bracket bolts known to break easily? Quote Link to comment https://www.bigmacktrucks.com/topic/34753-tranny-cooler-questionauto-trans/#findComment-233603 Share on other sites More sharing options...
gearhead204 Posted February 20, 2014 Share Posted February 20, 2014 take a look at the side supports do the bolts have nuts? or do they thread into the support? I'm guessing its like my superliner and they thread. With as low as that truck sits I'm guessing it would get road splash in that area and could be a bitch Quote Link to comment https://www.bigmacktrucks.com/topic/34753-tranny-cooler-questionauto-trans/#findComment-233619 Share on other sites More sharing options...
macattack Posted February 23, 2014 Author Share Posted February 23, 2014 well out she came. actually quite easy. no crossmemeber just a skid plate to remove. 34 bolts on the bottom tank and out she came. gonna have the rad shop check it out and rebuild. what do you guys suggest using to flush the cooling sytem. Quote Link to comment https://www.bigmacktrucks.com/topic/34753-tranny-cooler-questionauto-trans/#findComment-234192 Share on other sites More sharing options...
staxx Posted February 23, 2014 Share Posted February 23, 2014 Cacade dishwashing detergent ,use the liquid form or pre mix some with hot water then add to your cooling system and flush 2-3 times and should be ok . 1 Quote Link to comment https://www.bigmacktrucks.com/topic/34753-tranny-cooler-questionauto-trans/#findComment-234281 Share on other sites More sharing options...
rsb502 Posted February 26, 2014 Share Posted February 26, 2014 And that is why I don't like liquid coolers, air to oil is the only way to avoid that problem and they keep the trans cooler. Figure if your engine gets hot so does your trans, I talked to an Allison guy about the MT643's in buses years ago and he told me to get a separate cooler. They were built with water to oil coolers and he told us that if the trans gets over 200 you will have issues, hell the engines ran 185-205 all the time so so did our transmissions. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/34753-tranny-cooler-questionauto-trans/#findComment-234772 Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.