Scared half to death!!

Heading off to Pheonix during the fourth of July weekend (nephews down from NY) One problem....no temp guage on my XJ. Won't have time to get a panel from junk yard before the trip (My XJ has no guages at all)
How are the XJs at highway speeds running the AC?
Should I make this a night run....?
Rick

theyre usually fine @ highway speeds.... after 35-45 mph you generally dont need your fans anymore..... wind just takes over (generally)....... what year is this XJ?

96

i got an 88 that is great at highway speeds (55-75) with the ac on and it blows ICE cold and the low setting

If you do the routine maintainance, you should be fine. Speaking from someone who lives where its hot.

As long as you have taken care of your cooling system with regular mainenance, have a clean radiator you should have no problems. If you want to spend an hour or so, drain the coolant, stick in a $5 prestone backflush kit, back flush it with the heater on. Remove the overflow tank and take it inside the house, clean it out, I just use Fantastic or 409 and reinstall it. Then refill it with new mopar coolant and distilled water in a 50/50 mix. Remember to burp the system to remove air. Personally I replace my pressure cap every year or so with an OEM one and I use the 7 hour prestone cleaner and go for a long drive, then back flush and refill. How old is the fan belt and the fan clutch ??, both of those are preventitive maintenance things that should be looked it. If the belt has cracks in it then replace it.

what does "remove the air" mean? I have seen it used frequently and seen some explainations. in the FSM and other manuals there is no mention of this. that of course does not mean it is not needed.

I too have a 96 with overheating problems and am at my wits end.

I saw mention of the seal on the pressure bottle. does that refer to the overflow plastic bottle? if so, I do not see how the plastic cap and bottle would hold up to any kind of constant pressure.

With no temp gauge, I wouldn't recommend flushing the system before your trip. The problem is that you have no way to know if you get all the air out without the temp gauge to show it getting hot. The biggest risk of overheating is air in the system after draining and refilling it, so that puts you at more risk rather than at less risk of overheating with no gauge to show what's going on.

Air can get trapped in the system when draining and filling it, so you end up with a bubble. This hinders the circulation of the fluid and reduces the amount of coolant in the system. This is a common cause of overheating in the 4.0L motor.

If you're rig hasn't been overheating, and all the hoses and fans are in good condition, it shouldn't overheat. But, if something happens to the system on the trip and it gets hot, you may not know about it in time without a gauge........no way to avoid that risk.