Any takers on what this means ? 95 xj 4.0

 

How many miles are on it? When was the last oil change?

 

What good can come from going 75mph? I would think the Tranny fluid since 75mph is high rpm Higher heat.

It often means that you are burning antifreeze. Sometimes when the head gasket goes or going it will produce a passage for the antifreeze to pass from the capillaries into the combustion chamber. It is easy to check if you have an air compressor. Remove one of the rear sparkplugs and the radiator cap. Fill the radiator and then push some air into the sparkplug hole (get a good seal in case a valve is open). Repeat with all the cylinders and watch for air bubbles coming up into the radiator. If bubbles come up or fluid is pumped out, the head gasket is blown and must be replaced. It is more likely to happen at the back of the engine because it is farthest away from the fan and therefore gets less cooling. Also check your oil for discoloration. If it is a brownish color it could mean your oil and antifreeze are mixing and has the potential to damage your bearings.

smoke or semi white can be produced in several ways. One way is oil this is normally a whitish blue to blue smoke and has the apparent smell of oil being burned. Next could be antifreeze when it is being burned it has a sweet type of smell and tends to dissipate in the air rather quickly. Next is automatic transmission fluid which is normally found on automatic transmissions and its normally drawn into an engine thru a vacuum line via a defective transmission modulator valve or some other defective part. Transmission fluid is very apparent and billows out so bad that you can't see anything behind you. Last but not least another type of smoke that is not white but black is the presents of to much gas/fuel being burned in the engine. PS the one good thing about transmission fluid being burned is it is an excellent way to clean the carbon out of an engine.

 

forgot brake fluid ive seen a brake booster be half full of brake fluid and be sucked in a motor thru vacuum tube it also smoke horribly and white.

 

Agree with this could also be a cause. The fix. don't drive it 75 MPH haha

 

question for op any fluids being consumed ?

 

check your rear axle, if its a dana35 the outer bearing could be going out boiling the fluid inside. if you see fluid leaking out of the axle do not drive it cause your axle shaft is held in by that bearing and is about to come out. look for leaks in the tranny/motor to it could be getting blown on the exhaust at that high of a speed.

 

Agreed. A close monitoring of all fluids looking for level drop is always on the "to do list" for this symptom. Especially antifreeze.

 

White Smoke = antifreeze/coolant
Dark Smoke = Oil

Time for a compression check.