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Mystery coolant leak

2017 Views 86 Replies 11 Participants Last post by  Wc203
Hey guys I have a coolant leak from my 4BT and am convinced it’s my freeze plug , but I wanted to do my due diligence first before pulling the trans and T case to make sure that’s what it is . There’s coolant leaking from the bell housing cover dripping down to my sway bar and trans . No other obvious leaks . And unfortunately no access to the rear freeze plug due to the AA adapter to my 4L85E trans…. Anyone have the Cummins # for the rear freeze plug or pictures so I can see what I’m working with , couldn’t find anything on the web.
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I was hoping running it non IC with the super 30 would actually lower EGTs.. since it’s not getting 180* air from the coolant
Well it should as long as your fueling is fairly modest, I'd bet that it will be better power for the same EGT that your previous set up and with the IC WAY better...$.02
Unless you have lots of room up front, have to start from scratch on the front end when you decide to put i’cooler in, might want to at least mock it up while apart and get engine set back, lower crossmember, doghouse built, etc., while all apart!

Ed in CO
Setting engine as far back and as low as possible will have many benefits before all is said and done...$.02
I have set mine for 1,200* max with a 2-3 minute WOT pull up a interstate grade, I figure that is about as long as I'll likely ever need it to do that so not gonna hurt things.
At highway speed on level ground 700*/800* seems to be what I see and that is 75mph at 2,150 in my 8,000# brick, when accelerating at less that WOT it seems that 900*/1,000* seems to be where EGT's tend to be. Now I'm at 5,000' and most of the summit's here are 6,000'/7,000' so my #'s are a bit higher I would guess that if I were closer to sea level.
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