heres one for you guys. i have a 1995 cherokee se, 4.0 HO. its my daily driver or i wouldnt care. every few days i have to pour almost two gallons of antifreeze into the coolent system. my oil is black, so its not going there. exhaust is clear, even on first start after a couple days, so its not going there. ive run a dye leak test, and get no results from that, so its not leaking outside. my carpets dry, so its not leaking inside. where the h#ll is it going! it even emptys my overflow bottle, which dosent leak, cause it will be at the same level 24 hours later without starting. I AM LOST! 3 years of automotive college, and im stumped.

 

Have You checked the hoses when pressurized for pinhole leaks? You say it's not in the oil so the only options are out the Exhaust or on the ground.

 

It has a limited number of places it can go right?
If your positive it's not in the crankcase (oil)
and Your positive it's isn't going out the Exhaust.(steam?)
And you say there isn't any leakage, If it's pulling from the overflow bottle then it is being lost while in the cooling system, and the cooling system is recovering from the bottle as it should.
Is it an automatic tranny? There are cooling lines from the tranny going through the radiator.But the tranny would be full of water!

My bet is that it's being burnt off in the combustion chamber as you drive, Get someone else to drive it while you follow them and watch for puffs of steam ! Also a quik look at the plugs should tell you if a cylinder is being washed down compared to the rest...

 

milmat1, i didnt even think of the trans, thanks! if its being burnt, its doing i slow, if its leaking on the ground, the dye tracer isnt picking it up.

 

Check the compression and do the leakdown test to see if it could be getting past the head gasket into the combustion chamber. Also a pressure test on the cooling system seems a good idea too.

 

ok, thanks guys!

 

ok, update on coolent issue. nothing in the trans. i have driven the jeep more this past week than usual, bottle level has not chainged, radiator is full. im totaly lost now.

 

i hope someone solves this cause ive been doin the same thing on my 2000 xj just not as muh same result it never overheats or anything checked for leaks none visible

 

found the leak. pinhole in one of the heater lines. it gets hot and expands and leaks, cools and stops. replaced hose and nothing lost since.